You will need to contact Leader Fox to answer this question.
The Leader Fox website does not have any information on which of those numbers is the bicycle serial number.
Here is a link to the manuals for their bikes.
Their manuals do contain information on the serial number for the motors on their e-bike which is not the same thing as the serial number for the whole bike.
Here is a link to their contact page


Is this road/city frankenbike concept a feasible idea?

I think your idea is sound, a lighter alloy frame, with decent tyre clearances to allow the comfier larger tyres.

Hub dynamos go in the front of any standard wheel.  There's nothing particularly special, as long as the axle mounts suit the frame's fork.  That's probably nuts and bolts, rather than a QR or other quick removable fastening.  Also wires - you'll probably end up with externally routed power cables because internally routed ones would be hard to retrofit.
Lock - I am unfamiliar with the lock, but based on this image its just a chain in a tube that is fastened to the bike permanently, but offers no protection to the wheels.  Its an abus lock, just buy one of similar size and carry it in your basket.

Brakes - you'll need two independent brakes, one on each wheel.  Whether you go disk or caliper or canti or V brake will depend totally on what mounting bosses are on your frame.  That will dictate whether your wheels need a brake track or a rotor mount.  A CX frame will probably be cantilevers unless its from the last couple years.
Tyres - thickslicks are susceptible to punctures.  I have a lightly set laying around and haven't found someone I hate yet to off-load them to.  Based on the lock pic, the default tyres are fairly large.  You want to keep that sizing or similar.
Chainguards - ugly things.  Consider a belt drive instead, which will be a fair match for your IGH.
Mudguards/fenders - they're all a bit large, because they have to sit close to the tyre and cover at least as wide as the tyre.  Mudguards also should go quite low behind both wheel, so you're stuck with at least 1/4 to 1/3 of the circumference on the front, and a bit over 1/2 a circumference on the back.

Alternative idea #1   Since you like basically everything about the vanmoof, consider checking their current lineup for a model more to your current requirements.    Their website doesn't list weights, but some resellers might.

Alternative idea #2   Strip the usable bits off your current bike and fit them to a replacement frame that suits you.    Its an option, but I'd suggest your existing bike has a value and can be sold on to fund the new one.


The Jeep is a giveaway.  There really was a Raleigh Jeep.  It's on page 7 of this 1971 catalogue.

You're right, it was meant for girls.

That massive headlight isn't original.  Otherwise it's a nice looking bike that needs some work.


Shimano/third-party rotor compatibility with low end hydraulic brakes

As you mention SM-RT54 and 66 rotors, I will infer you have Deore level calipers. (Deore is not 'low end' IMHO, as the 'cheap A's' (Alivio, Acera and Altus) and almost unmentionable Tourney are below it.)

If you check out the Shimano Product Line docs for Deore you will see that the SM-RT64, SM-RT54, SM-RT66 and SM-RT56 rotors are all compatible with the BR-M6000 and BR-MT500 calipers. The SM-RT64 and SM-RT66 are both metal pad compatible.

Note that the BR-MT500 caliper is not metal pad compatible though, so you should check your caliper compatibility.


I have once taken a boxed bike on a train from Bath to London airport. There wasn't really any space to put it somewhere, so I just put it upright next to one of the entrances and stood next to it for the ride. It wasn't a problem and noone complained about it. However, I also didn't ask anyone if it is legal or not.


Don't rely on the racks locks alone to keep you bikes safe. They willat very best, slow the thief down (shows the point).  A hitch rack provides a good lever that can be effectively used to snap the rack (or the hitch) off to take the bikes, and if the bikes are damaged in the process, the thief just walks away leaving a mess.

Strong cable lock though a closed loop on the car (the cars tie down loop / eye)  around the bikes, threaded to limit the range of twisting and lever motions, meaning the racks locking mechanisms cannot be push further than they can cope with.

For any length of time, take the bikes off the rack and store safely inside, or out of site locked to a secure rack. Cheap bikes also help.


By looking at the current frame geometry at http://www.giant-bicycles.com/en-gb/bikes/model/anthem.x4/7865/45505/#geometry we can assume the following.

Descending:

HA: 71 degrees head angle is pretty steep for downhill but for flowy singetracks it will be good. For the "steepish rocky tracks" it really depends on what you consider steep. Anything more than 10% and at over 15km/h may feel uncomfortable on the 71 degrees HA.
cockpit: You can improve the descending characteristics of the bike by using a shorter stem and wider bars.
travel: The 4 inch front and rear travel will not be enough for the very rough stuff.
verdict: So if you are very interested in aggressive MTB trail riding then this bike will not be appropriate. If you are just starting out then it'll be OK.

Climbing:

HA & SA: The 71 HA and the 73 seat angle make for a great climber.
travel: The 4 inch front and rear travel make a great XC bike and will allow you to easily tackle long epic rides on the mountains (for example 30 to 80km rides). Increasing suspension usually reduces this number.
verdict: Really good climber especially if it'll come with good (light) wheels and appropriate tyres.


How does paraffin chain wax perform in winter conditions (snow, road salt, -20° C)?

I posed this question directly to the people at Molten Speed Wax and got this reply:

Our product works great in winter, the key is to put the chain on the bike inside and run it through the gears when the chain is still warm from the pot. The reason is a newly waxed chain is very stiff in super cold temps., but if you pre-break in the chain before going outside it eliminates the problem. This is a tip we give to fat bikers who race in temps.well below zero F.
Concerning salt and sand, that's really tough on any lube. The fix is to have a backup chain or two so if you ride in wet conditions for some time you can quickly change out a chain with a fresh waxed one. Short rides in the wet are no problem but when in doubt re-wax. We ride outside year round and Minnesota is notorious for sand and salt, but wax performs really well.
One last note, don't worry about wax flaking off. Some excess will flake off but all you need is a very thin layer on the chain and that will stay on the chain, particularly on the inside, where all the friction is.
In sum, ride wax year round, no problem.

Obviously they’re promoting their own product so I’ll take their advice with a grain of road salt, but I think I’m convinced to try it and report back.


Why do some triathlon seatposts go straight up and down instead of at an angle?

To crudely simplify things, a triathlon/TT bike position is much the same as a road position, but basically "rotated forward", so your arms rest atop the very-low-set bars. A consequence of this is, the seat ends up further forward.

(source)
Using Chris Froome's TT position as an example, noting the hip position versus the bottom-bracket position:

(source 1 and source 2 - I couldn't find a good side-on picture for the road-position, so it has quite a lot of skewing to align to the TT-position picture)
This "Proper Bike Fit for Triathletes" article has a vastly more detailed explanation (and is the source of the first diagram!)

Doesn't this also mean that the straight-up vertical adjustment of these special triathalon bikes do not fit as wide a range of riders as if the seatpost adjusted in a way that kept the same torso/leg angle along the axis?

As long as the frame is roughly the correct size, the tri bike should be just as adjustable as a road-bike, if not more..
Look at the tri bike image in your question - the saddle rails cover around 3/4 of the length of the saddle, allowing a greater range of movement forward/backwards (compared to the road bike, where the rail often covers less than half of the saddle)
Additionally, the aero-bars are much more adjustable than standard drop-bars (which are mostly limited to stem-length adjustments). Aero-bars can potentially be moved quite far forward or backwards (although at some point you will hinder steering/stability)


Jobst Brandt says it doesn't matter so long as the pattern is mirrored over the hub. There is an argument (small) for having pattern #1 on the drive-side rear to reduce the chances of the chain getting stuck in an over-the -cassette disaster situation.


Fork trail vs chainstay length in steering

Because you steer a bicycle with the front wheel (and weight offsets), the steering of a bicycle is almost entirely determined by the geometric parameters of the front wheel and where it is located. The most determining factors are:

Trail
Wheel flop factor
Front wheel radius

Trail and wheel flop factor are determined by steering angle, fork offset and wheel radius.

The chainstay length is irrelevant in this respect, but it does matter for the overall handling of a bicycle. For example it has an influence on how well a mountain bike climbs. For road bikes it has some influence on the weight distribution between both wheels.

There are tandems which handle like a good road bike (except for the turning radius). They essentially have "chainstays" that are almost 1.5 m long.


Is it bad to keep hydraulic brakes engaged for many hours?

Short answer?  No, it will not generally cause you a problem.  This is actually a common method of parking a loaded touring bike.

Don't over tension the brake lever.  Remember that a hydraulic lever doesn't require excessive force to have power at the brake.

A simple 6mm rubberband wrapped over the lever and handlebar should accomplish your purpose.


What does 'orbital' mean when speaking wheels?

Orbital is the brand name of the hub. 15mm and 20mm are different axle diameters, get the one that matches your fork.

Edit: Most dirt jumping, DH and freeride forks use 20mm, 15mm is a newer standard used mostly for cross country.


How can I repair a tyre with a deep cut?

You should be able to patch the tire with a tire boot, which you should be able to pick up at your LBS. It's basically a rubber patch that you apply to the inside of the tire, where a gash is. Similar to a tube patch, but thicker. There's all sorts of things that people use for makeshift boots, too, such as a $1 bill. The important thing with a boot is that it prevents the tube from herniating through the gash.

Park Tools Emergency Tire Boot


Modifying SKS Race Blade Long for solid axle hubs

If you enlarged the hole on those, there's really not going to be much material left. I'd worry about it getting mashed to nothing under the nuts.

The other thing is that the knurled surface and generous dropout contact area on track nuts do a lot to keep the back wheel in place. Messing with that seems bad.

I would use either p-clamps or, if possible, an appropriately sized random plastic bracket.


What to call bike brake levers with two gripping points?

I was hesitating to flag this post as a duplicate of Why don't brakes come with 'Safety Levers' any more?, but the other post is rich in the names of those "dual-pull" brake levers which in fact answers the OP's question.

So the names are:

Dual pull
Safety Levers (manufacturer's term)
Extension Levers (Sheldon Brown)
Suicide levers (wikipedia)
Auxiliary levers (wikipedia)
Interrupter levers - these are the additional brake levers placed along the brake cable. Although their position is similar to those mentioned above, they operation (and effectiveness) is different.

I hope this gives the OP enough possibilities to chose from.


Short answer, no, there isn't a non-replacement option at this point.

Partly because the Dash is a very basic shock, and thus repair becomes not cost effective compared to replacement.

Repair in this case involve replacing the damping cartridge, seals, and oil, which is basically all the internal parts if it's an air sprung model.

(A coil spring model would also have a spring side.)


You probably can't fit a bigger front chainring on that bike due to the front derailleur and chain issues. They do make 11 toothed 7 speed cassettes which you can install (but I doubt you'll gain anything from it due to the second point I want to make on cadence), which will give you a bit higher gearing but the spacing between the cogs (i.e. the number of teeth) will be worse. Note that a higher gear ratio isn't always advisable, since you need to remain in control of the bike at speed as well (there isn't really engine braking, like there is on a car, in a derailleur system). Also, if you're commuting, you don't want to be going so fast that you get drenched in sweat when you get to your destination, so speed isn't everything.

However, chances are you need to increase your cadence: http://sheldonbrown.com/gears/ says that at a 60 rpm cadence, you should be doing 19-20 mph in the 48t front, 12t back combo, which should be enough (the 700cx37 tires aren't on his calculator, but 35 and 38 are close enough). Your cadence might change if you're in an improper riding position (e.g. seat too high/low or weird handlebar positions).

EDIT: The tire size on this bike should be 700c x 42. But the point still stands (the speeds should be slightly higher at the given cadence, since increasing the tire size also increases the gearing).

You should also make sure your bike is tuned up (you may feel sluggish if your hubs are due for a repacking or your brakes are dragging on the rims or your tire pressure is too low, for example).

If your cadence is already sufficiently high for some reason, time to get a road bike then (which will probably be lighter and more aerodynamic and have higher gearing (both at the bottom and top end)). Note that there will be a geometry change, even if you go with a flat bar road bike, probably, so if you choose to go this route, make sure to get fit. What you've got is a pretty heavy (~30 lbs, which is fine for its intended purpose) and cheap hybrid which is designed to be a commuter - it isn't really worth pumping money into it to improve it, but only to fix the things which are broken and add things useful for commuting, such as lights or switching to slick tires (which you presumably already have).


Would variable crank arm length be beneficial to a rider?

The system you propose is just a third way to change gear, in a mechanically very complicated way. Any benefit that could be obtained by lengthening the cranks can already be obtained by moving to an easier gear and a bike with two or even three front chain rings and anywhere between five and eleven rear sprockets has plenty enough gear ratios available to cover all situations. And if the range of gears available isn't wide enough, replacing the chainrings and/or rear cassette is a much simpler fix.


Can't fit damper back into suspension forks

Something is likely blocked or broken inside, and there's not much you can do it about it unless perhaps you contrive a way to open it up, which probably wouldn't be all that reasonable to attempt given the hassle and low ultimate odds of success. They're meant to be unserviceable in every way.

In a shop context the thing to do is call Suntour on the chance they either have a replacement (possible) or a fix (unlikely), or would warranty the fork  Their US office is helpful; don't know where you are though. If not that then replace the fork, which is usually where this goes one way or another.


Squealing/whistling noise that gets higher-pitched the faster I'm moving

If the noise is related to road speed rather than pedaling force or cadence, it's coming from the wheels.

I doubt that dust is the problem, bearings have dust seals and dust settling downward on the bike isn't going to get into any bearings.

Hold the bike off the ground, spin the wheels and see if you can recreate the sound. Check brake pad clearance. Disc brake pads rubbing on the disc can make a high pitched sound. You can also check the wheel bearings for play by pushing and pulling laterally on the rims.


measuring a spoke that's already in a wheel

If the hub flanges are the same diameter, a slightly inexact but highly likely to succeed rule of thumb is that the calculated lengths for a conventional three-cross 26", 27.5", or 700C disc wheel are likely to give you a difference of right around 1mm in optimal length between the right and left side, so if you know your existing left spoke is optimal than just getting 1mm longer is likely to work. (The number is right around 2mm for non-disc rears). Unfortunately there are some stumbling blocks. Usually the actual difference in calculated length is more like .9mm-1mm for fronts and 1.2mm for rears, which means that there are corner cases where if you did this in front where the left you had was at the stone limit of thread length and you added 1mm, you might run out of thread length and the spoke wouldn't work. If the spare you have is the same as what's in the wheel, you could pull off the rim strip and check how the thread engagement is looking to preempt this. That would also let you know whether to get the same length or that length +2mm if you went to buy the spoke and found they only had 2mm increments, which is pretty common. Note this rule of thumb doesn't work the same for smaller wheels or cross patterns other than 3x.

You could just calculate it using a published ERD (effective rim diameter), and if you had an accurate ERD then that would work well since you can measure the hub, but the problem there is that published ones often aren't quite right, sad but true.

A pretty exact length can be found by reverse-calculating the ERD if the left spare you have is the same as what's in the wheel. You can pull off the rim strip as above and do a careful measurement to determine its exact difference from optimal length, probably easiest done by counting visible threads and multiplying by the thread pitch. Measure the spare, add or subtract that difference from optimal thread engagement, then measure or estimate the left side tension on the wheel and use either math or something like Machinehead Wheelcalc to get the amount of spoke elongation the ones in the wheel currently have and factor that in, and the result should be the ideal "stretched" left side length. After measuring the hub, you then have all the tools you need to use a spoke calculator like Damon Rinard's spocalc.xls to reverse-calculate the ERD of the rim by plugging in different ERDs until you hone in on the one that matches your measured optimal stretched left length, and then the calculator will also be telling you what the ideal right side stretched length is, from which you'll then have to compensate for elongation. (Good spoke length calculators use the classic spoke length formula that works off the pure geometry of the wheel as though it were just a bunch of circles and lines, and leave it to you to compensate for elongation.)

If you wanted to just measure the built wheel to get an ideal spoke length, use a tape measure, piece of string, etc to get the most accurate measurement you can from the inside of the J (the actual point of contact with the hub flange) to the point where the spoke inside its nipple intersects the inside surface of the rim. It can be tricky to measure so do it a couple different ways until you're confident. From there you want to add the thickness of the rim including eyelets if present and the thickness of the head part of the nipple, and then subtract for elongation. You can get the base thickness of the rim by snaking the depth gauge part of a Vernier caliper through the valve hole. 2mm is a good general number to use for the nipple head height; that errs low but that will result in spokes that are slightly short rather than slightly long, which is what you want so that you don't run out of thread length while trying to change a spoke in the middle of nowhere. For the elongation, .5mm on the less-tensioned side and .8mm on the full-tension side are pretty safe general purpose number for either 2.0 or 1.8mm spokes, but there are more exacting approaches that can be taken.


How can you identify if a Shimano rear derailleur is medium or long cage?

The picture is a RD-M780-SGS long cage.

Shimano have three codes for rear derailleur length:

Short - SS
Medium - GS
Long - SGS

I'm not aware of where this is printed on the RD though so not so helpful.

However Shimano only have one non-clutched XT Dyna-Sys (10 speed) RD the RD-M780-SGS (long cage 43t capacity). The clutched (shadow+) RDs come in GS (medium 35t cap) and SGS (long 43t cap).

Saint derailleurs come in SS (short 23t cap with cassette extender) and GS (medium 37t cap with cassette extender) for more gravity focused 1x set ups.


Is the term "24 inch gear" universal (in the context of fixies)?

"Gear inches" is universal enough to have a Wikipedia page:

Gear inches is one of several relative measures of bicycle gearing, giving an indication of the mechanical advantage of different gears. Values for 'gear inches' typically range from 20 (very low gearing) via 70 (medium gearing) to 125 (very high gearing); as in a car, low gearing is for going up hills and high gearing is for going fast.
'Gear inches' is actually the diameter in inches of the drive wheel of a penny-farthing bicycle with equivalent gearing.


Seatpost of a folding bike is always dirty, filed down by frame?

If you have an old inner tube available cut a section slightly longer than your seatpost. Slip it over the seat post and zip tie it in place. It will act as a somewhat water/dirt resistant boot, similar to what mountain bikes have on the front shocks. You may have to look for a fairly wide tube to fit over the post. Check with your local shop to see if they have any unrepairable ones left laying around.


I've done a great amount of testing and investigating bicycle bearing greases and anti-seize pastes. My conclusion, opinion and experience is that for bicycles, any anti-seize will do. Relatively low pressures and temperatures don't create serious challenge for the anti-seize.

My first choice is kaolin and titanium oxide based anti seize, since it is white (doesn't look like rust to bike shop customers, so less explaining if some is left visible) and very easy to wipe off the places where it isn't needed. The one I use is Famol PT, but look for a locally distributed/manufactured version. Or use any other anti-seize.


Disk brake caliper fit, inboard width of calipers

I'm assuming the question is about physical interference between the caliper and the wheel, namely the spokes.

The fork isn't the determining piece here, because a given wheel and rotor is going to want the caliper to be located in a certain position relative to the wheel. In most (maybe all) cases where there is an interference problem, changing the fork wouldn't do anything about it.

The way this has played out for the most part is that some calipers have come out and been found to have issues with interfering with spokes on some or many wheels once in the wild. TRP Spyres were an example; when they come out in 2012-13ish they constantly had issues with running into the spokes of bikes people tried to put them on. I believe they fixed something in that design in a generational change because I haven't seen the problem in a while.

There are no measurements that brake manufacturers provide that let you predict the issue. It's become an unusual problem, even with large flange hubs. For the most part it's going to take a very wide design like the Spyres for a problem to even come close to being possible. The standard practice is to basically ignore the possibility of a wheel/caliper interference problem until it bites you.


What tool do I need to disassemble this 5 speed freewheel

I found a bunch of forum posts from people with similar problems. Shimano freewheels made prior to about 1985 have smaller diameters, about 20mm instead of 22-23mm that they have today.

A search for "Shimano freewheel remover 20mm" brings up some useful results. It looks like Bicycle Research Tools makes a remover called the CT-4 which is designed for older Shimano freeheels.

Good Luck!


Inertia.  Bottles are about that big because that's how big bottle cages are, because that's how big bottles are.... repeat.
Another cause is that a 10cm bottle would be larger and harder to hold/easier to drop while riding.  Most riders would drink while rolling on the bike, so its potentially bumpy, with a layer of sweat/sunscreen/rain making things a bit slippery too will add to drops.
Lastly - added width will poke out into the airstream more, contributing to a drop in aero efficiency.  There are some expensive bottles that are deeper vs their width but they cost a lot (hundred dollars a bottle ?!)  and their overall capacity is probably no-more than a regular bottle/bidon.

The width also limits the chance of clipping one's bottle with your feet while pedalling hard.

Later: you reminded me of the Growler Cage - its designed to hold a 64oz jug (about 1.8 litres) and the vessel is between 4" and 5" wide (100-125mm) depending on material.  You'd want to avoid a glass/ceramic one, and would choose stainless steel or plastic.
Also be leery if you're transporting anything across boarders/state lines or into a jurisdiction with different alcohol laws - even when filled with water, these look like they might hold booze and could attract legal and/or criminal attention.

Downsides of this is that its enormous, adding significant mass to your bike and only held on by two bottle cage screws.  Those might be enough for a single bottle, but this is ~twice the weight and has more leverage on those same bolts.
Also, as reported these are likely to hit your feet, pedals, or cranks on every rotation.  That gets annoying really fast.  I'd expect to tap it with my calf muscles or trousers too.


What did I just do? Fluid shot out of my handlebar when pushing my caliper in

The LBS said I pushed out a valve or plug - They said on some MB systems there is a 1-way valve that will deal with this in case there is too much pressure but the system I have lacks it. It was a simple fix, they pulled the plug, cleaned it, bled the line and replace the plug/valve. - They charged $40 (in a super expensive area)


Screwing reflectors to pedals - what washers do I need, and where?

Danger danger!
I have used those reflectors and they are a piece of crap. The failure mode is the plastic breaking. Your shoes will damage them in no time. I'd expect 2000 km use out of them. Then you'll see the plastic holder is damaged and the plastic reflectors have been shattered and lost. The only things in these that don't fail are the metal parts.
If you use PD-M324 pedals, instead purchase orange ECE-R104 reflective tape. It is readily available in long lengths because in some jurisdictions trucks have to use it to mark the perimeter of the vehicle. 5 meters long x 5 cm wide costs less than 10 dollars/euros/whatever-similar-currency-you-use. You can use one roll to reflectorise 50 pairs of pedals once, or one pedal pair 50 times. Thus, one pedal pair costs 0.2 currency units to do.
The reflective tape lasts longer than the plastic reflectors, is probably about as good in reflective power, and it's much cheaper to install.
My current solutions is using PD-T8000 pedals that have the plastic reflectors factory-installed and mounted in a durable metal enclosure. They last a long time too. Besides, the benefit of PD-T8000 is that they have a "heavy side" and a "light side" so every time you stop they are in a well-determined position, so you can time your feet in such a manner that you can repeatedly hit the platform side or the cleat side. Also PD-T8000 are much lighter weight than PD-M324.
But if you want to use PD-M324 despite their shortcomings and don't wish to upgrade to PD-T8000, do use the orange ECE-R104 reflective tape.


Retrofitting disc brakes on 2000 Specialized Stumpjumper FSR XC?

The caliper is touching the wheel because the caliper was designed for a disk to be there, but the wheel was designed for spokes to be there. With a disk-brake wheel, the spoke flange on the hub is moved closer to the centerline to make room for the disk, which would be where the spokes are now. There are only a few standards for mounting disk brakes, which determine where the disk and caliper should be relative to specific points on the bike. Unless you want to mess around with adapters, you need to make sure all your parts fit the same standard. I'm guessing your fork uses the 74-mm post mount standard.
This distance is called the over-locknut distance. Almost all bikes use a 100-mm standard for the front wheel. There's a more recent 110-mm standard (called "boost"). The fact that you're getting 103 mm is probably a measurement error, but that's a 100-mm hub, and you should continue to use 100-mm hubs.
Not really. It's not clear exactly what kind of rim is on that motorized wheel, but you can probably mount a fatter tire on it if you want.


Is there a way to convert from a dropout frame / fork to a quick release / thru axle?

Short of cutting off the dropouts and welding/brazing/bonding on through-axle fixtures, no, you can't convert between them.


Fit thinnest road tyres (fat ones at present) to terrain bike Outpost GT

The K898-005 is a Kenda model code that no fitting information can be gleaned from directly. The 54-559 (you wrote 359) is the ISO measurement. The first number (54) is the approximate outside width of the inflated tire in millimeters, approximate because it varies slightly depending on the rim width it's mounted on. The second number is the diameter of the circle formed by the tire bead, which corresponds to the bead seat of the rim. 559 is the most common of the 26" sizes, sometimes known as "mountain bike 26 inch" and similar names. It's probably the actual most common size in the world, but there are a couple of other 26" sizes, and when getting 26" road tires it can be easy to accidentally get one of those instead because they're more commonly associated with thin tires. So don't buy a tire that says 571, 584, 590, or 597. You want it to say 559. Most but not all tires for 559 are going to have their width described with a decimal rather than a fraction (26x1.125 rather than 26x1-1/8 for example). Most but not all currently produced tires have an ISO number hiding somewhere on them, so you're looking for something that says xx-559, where xx is width.

As for the minimum width, for practical purposes you want something that ideally has 2-3mm overhang past the rim and is under no circumstances narrower than the rim. So 26x1.25 (32-559) is the start of the reasonable widths, 26x1.125 (28-559) is pushing it, and 26x1 (25-559) will more or less physically work but is kind of asking for trouble.


Just buy the best bike you can get for the money you have. Component upgrades cost less money when bought as part of a whole bike, compared to being purchased and fitted separately.

As an example, the price difference between a bike fitted with 105 and one with Tiagra is a lot less than what a 105 groupset costs.

The difference can be defrayed by selling the original components as new take-offs, but it's a hassle and you probably still will not make up the difference.

If I were you I'd look for a used bike in good shape, rather than deal with Halfords level bikes.


51cm top tube too small for someone who normally cycles frame with 55cm top tube?

There are two lenghts on a bike that are crucial for bike fit:

Seat tube length, which tells you how much of your seatpost will be outside the frame;
Effective top tube length, which is the horizontal distance between the centerlines of seat tube and head tube. This tells about your reach to the handlebars, how much the bike will feel "long" or "short" to you.

Some time ago, almost all the bikes had an horizontal top-tube, and due to manufacturing constraints (lugged frames using lugs with fixed angles) they tended to have a certain proportion between frame "height" and "length" in order to fit the average rider with a certain height.

Today we have a widespread adoption of welded frames, sloped top-tubes, mirabolant geometry designs, and we should always consider variations in leg-torso proportion for people with the same height.

That's why I think is safer not to consider the relation between  one of length/height of two frames to have a correspondent variation of the other measure. In other words, is perfectly plausible to have two frames with same seat tube lenght and significantly different effective top tube length, and vice versa.

So, to answer your question: Yes, you can ride a frame with a 51cm seat tube lenght, achieving a similar fit, IF the effective top tube length of the frame is similar to the corresponding measure of the former 54cm frame.

EDIT: Unfortunately, since the frame you are looking at is a 51cm top tube, it is unlikely to be a good fit.

(EDIT: I thank Zenbike for editing my question, because I had mistaken top tube for seat tube and didn't even notice. Usually only the seat tube length is informed, and end up being considered as "THE" frame size).


My bike key is broken off inside the lock

Is it a cable lock like in the image? If so, bolt cutters. You'll be surprised and dismayed to see how easily you can cut a cable lock with a set of bolt cutters (maybe enough to invest in a better quality lock?) They're cheap, easy to find, and will get through most wire cable and some chain (depending on hardness.) They're also the go-to for most bike thieves, so don't be overly conspicuous about using them.


can a single sprocket be locked on a road bike?

How about a Schlumf drive?

  The Schlumpf drive is an ultra thin planetary gearing system located at the right end of the bottom bracket, between bottom bracket and right crankarm. Installation of a Schlumpf drive hardly changes [either the] position of the chain nor position of the crankarms.

They're probably expensive, but I don't think they have a freewheel. Plenty of people use them with hub gears for extra range. You tap the centre with your heel to shift - not as easy or quick as a lever on the bars, but they look pretty minimalist as they don't have any cables, which seems to jibe with the fixie way (if I've understood it right?)


It sounds like that spoke was carrying a lot of tension by itself. Perhaps because the wheel had been damaged previously. When the spoke failed, the nearby spokes on the side with the broken spoke weren't tight enough (or plentiful enough) to support the rim and it was pulled into the warped shape.

It could be that the way you were riding at the moment (if you were maneuvering or climbing – anything that would put an unbalanced load on the wheel) may have contributed to the sudden change of shape, or there may have been stresses in the spokes and/or rim that caused it to warp when the spoke broke. Do you know anything about the history of the wheel that might help us sort it out?

If the wheel is well built with enough spokes and a rim that is appropriate for the use and the spokes are sufficiently and evenly tensioned the failure of a single spoke shouldn't be a huge event – you might find that the rim is dragging on the brakes a bit, but I wouldn't expect anything that you couldn't patch together well enough to ride home (assuming non-extreme conditions).

The caveat is that I tend to be pretty conservative – wide rims, lots of spokes, and I'm fussy about spoke tension. So I don't know too much about spoke failures on light weight wheels with a minimal spoke count. There I would expect the failure of a single spoke to be more of a problem.


eBay:

http://kleinanzeigen.ebay.de/anzeigen/s-fahrrad/k0

Open in Chrome and use 'Google Translate'. 'Fahrrad' is your keyword.

P.S. Most German people speak better English than some English people do!!!


Removing stuck front brake caliper from a modern road bike

This is an old post but it came up in Google. I had the same problem. It's worth trying a bit of heat. I used a hairdryer to gently heat the area and this helped the bolt come loose.


Why are chains sold in fixed lengths rather than by the meter?

They do. Connex (Wipperman) sells bulk chain, as shown by this link, and these people also buy it by the spool. This is likely what bike manufacturers do, and I've seen it in a bike shop or two. I'm sure you can also get it at some place like McMaster-Carr or Grainger if you ask for ANSI #40 roller chain with the appropriate width (possibly by special order).

The only bikes which use bigger chains than a standard chains are custom, longtails, tandems or recumbents -- its just more convenient for 99.999% of the people to just get a standard length chain [and many of these are pretty close to just taking multiple chains joined together]. As for the few extra links "waste", they come in useful sometimes when you need to do a repair. And in net, its probably cheaper to just pick up a little plastic box which has a slightly larger chain than going to the LBS and asking the girl to break the chain to the exact number of links you need (remember, she needs to get paid and do the daunting task of counting/comparing the # of links in your old chain to the new chain provided you actually brought the old chain in. if you didn't do that, she has to assume you didn't muck up the # of links in the chain and you wont complain if your new chain ends up too short). And its quicker.


Wahoo KICKR Core Smart Turbo Trainer and Giant CONTEND 1 2017 - Cassette options

Unless you upgrade your shifter to 11 speeds, then you don't want to use an 11-speed cassette. The shifter, the derailleur, and the cassette all need to work together. So unless you plan to do that, use a 9-speed Shimano cassette.
You'll need to install a 1.85-mm spacer inboard of your 9-speed cassette on your Kickr. It may come with one (check the "what's in the box" details).
You could get a tighter cassette if you wanted. It doesn't need to be the same gearing. Conversely, you probably could get away with an 11-34. Also, if you'll be using your trainer primarily in erg mode, then it doesn't matter what your gears are.


What kind of chain to buy for internal gears?

The chain you need is 1/8 inch chain, usually sold as singlespeed chain.

A derailleur chain, which are sold as multi-speed chains, is narrower and the cogs may be too thick to fit.

EDIT: As said in the other answers, some singlespeed and internal gear hubs have narrower cogs and can use the 3/32 inch chain. An 1/8 inch chain may be slightly noisier with these cogs, but works.


I had a similar problem, but through trial and error learnt that actually I was the problem, not the bike. If I change down to the desired gear before reaching the bottom of the ascent, there was no further problem.


Can't get lowest gear and derailleur shifts on its own

We know it worked once, but we don't know what was changed, so it's time to go back to basics.
Auto shifting
The rear derailleur has a spring that wants to move the chain to the smallest cog.
The shift lever should have enough friction to keep the derailleur spring from going where it wants but not be so tight that it won't move.
The first thing to check is that the wing nut is tight.
If the wing nut is tight and there is still auto shifting then it's time to check how the levers for correct assembly.
My guess is that you have shift levers that look something like this:

Check that all the washers are there and in the right place.
Low gear
There are at least three main things that can keep you from getting low gear.

Limit screws - you have checked them and they are fine. Just to make sure, can you move the derailleur by hand and get the chain to go into low gear? If so then we know it's not the limit screws.
Cable tension - with the chain in the smallest cog and the shift lever all the way down the cable should have no slack.
Derailleur alignment - here's a picture:

Picture from SOS Hanger


Are rusting screws a sign of cheap/bad material?

Stainless steel is rust-resistant not rust-proof, especially if the bike sees the outdoors a lot, it isn't uncommon for screws to get a fine sprinkling of brown spots. The good thing about screws is that they can be easily replaced.
If you were very enterprising you can probably replace your bolts with titanium ones. They don't rust in the same way as steel does at all. However, they are usually weaker than the equivalent steel bolts, so we would not recommend replacing bolts like the stem or seat clamp bolts without careful research on high-quality titanium bolts. If you do this, be sure to research titanium material grades; commercially pure titanium is likely too weak for structural bolts, whereas grade 5 (aka 6/4 titanium) is probably what you would want for these bolts. For reference, most titanium bicycle frames are made of grade 9, aka 3/2.5 titanium. The numbers for grade 5 and 9 reference the proportion of aluminum and vanadium in the alloy.
Painted components (like your bike frame) are naturally rust resistant because the paint prevents contact with oxygen, which means that the metal can't oxidise and also explains why its not a bad idea to touch up on large paint chips or scratches with touch up laquer.
ADDED a quick wikipedia glance explains that while stainless steel gets covered in rust, unlike regular steel the rust is passive meaning that it will just stay there (looking unsightly). With regular steel, rust has the nasty habit of eating away at the metal (it is an active oxidation site). The rust on stainless steel behaves like a coating that prevents further oxidation.
Additionally, see comments by @cmaster: not all steel bolts are stainless, particularly on lower-cost bicycles.


Shimano 105 early- to mid-1990s SLR groupset on eBay worth it for 70s SuperCycle rebuild?

For not much more than that ($600 dollars), you could put a new Tiagra 10 speed group on the bike. So in my opinion, no, that is not a good price for those components.

Even if they were unused, it would be a high price. You are the only one who can make that value judgement, though.

Do you want the vintage look and feel? Are the components unused? Do you think it's worth close to the same money as a newer, better quality group set?

Then it may be.


Missing lock nut part on Dura Ace WH-7900 wheels

It looks like the washer in your photo may be a "Wedge-Lock" washer like those available here: http://www.mcmaster.com/#standard-washers/=xhptlp

They appear to sell under the names "Heico-Lock" & "Nord-Lock".
This may be a UK source: http://uk.rs-online.com/web/c/fasteners-fixings/nuts-washers/locking-anti-vibration-washers/

I should note that there very well may be a similar looking shimano specific part that functions differently & that I am not familiar with. I'm basing this suggestion solely on appearances.

If someone knows that these are in fact not the same as the item pictured by the OP, please enlighten me!

EDIT: To add further to possible resources, at the bottom of this page: http://www.heico-lock.co.uk/products.html There is a list of "Wedge Lock Nuts & Wheel Nuts" (Nuts with an integrated washer half). I do not see any resale links though...


Anything from Shimano with 8 speeds should work. The problems can only start when your cassete's biggest sprocket is too big (you are well under limit).


What do I do wrong to get hip aches after biking?

I have personally experienced that precise symptom, from mountain biking rides or from commuting rides.

Although I am not sure what causes it, I have observed that when it happens to me, I have ridden up steep inclines in "too high" gears while remaining seated or seated too far back on the saddle. For these reasons I have changed my pedaling technique a bit, using a lot more gearshifts.

I can also recall that my problems appeared when I changed my saddle for a narrower one, so later I found that to accommodate my sit bone, I tended to sit further back, so I could catch a wider part of the saddle. No doubt I changed my saddle's fore/aft position by half an inch towards the front.

In some rare occasions I have gotten hip pain from riding in too tight, non stretching pants, like jeans, specially carrying objects in my pockets. I suspect the problem here is the pressure the clothing excepts over the hip joint while flexing up the leg. Objects like phone, keys or tools in the pockets make this worse.

Check if any of these issues is affecting you and, if you find so, try changing one thing at a time, to see if something helps.


Rattling of a Shimano Nexave roller brake

I have these fitted to my Carrera Subway 8.

They seem to work well, but yes they rattle quite a bit when going over rough ground.  The cooling fin becomes tight when the brakes are applied so must be a direct connection to one of the friction faces.

I might have a go a dabbing a bit of silicone at three points around the interface of the cooling fin to see if it subdues the rattling :-)


Straigtening a rim with 7mm deviation in a single section

You're describing the symptoms of a rim that's sustained an impact sufficient to warp the rim itself. In other words, if you took away the spokes and hub and layed the bare rim on a flat surface, with no spoke tension acting upon it, it wouldn't be very flat. But in a case like this there's nothing that happened to it that would also cause the spot on the other side to warp out evenly, like a parabola or potato chip or whatever. It's just tweaked.

When such damage is minor enough, it's possible to mitigate it reasonably well by truing it out. In this case, the truing process involves adjusting the spoke tensions to be unequal in a way that forces the rim to be straight. The limiting factor is if you push the spoke tensions too low on one side to achieve this, you have a wheel with a weak spot that may also have trouble staying true, and if you push the tension on the other side too high then those spokes will be extra prone to causing fatigue cracking on the rim. In contrast, a rim that's perfectly straight, round, and undamaged is made true by getting the spoke tensions as equal on each side as possible (although in reality there is some small discrepancy due to the seam, imperfections, etc).

The only way of fixing it is to bend out the warped spot. This used to be common in the earlier history of bikes, but is now a lost art in many parts of the world. Rims were also more often steel then, which lends itself better to actually getting fixed in this manner. There are various techniques for doing it and I am not an authority. Some people's technique involves first detensioning the rim to be able to judge things more accurately, but I've known old time mechanics with a lifetime of experience that believed in skipping that step, sometimes with the reasoning that the now-overtightened spokes on one side of the tweaked wheel will help the process go smoother, having the tendency to exert pulling force on the rim just where it's needed in just the right amount. The main apparatus I've seen for it is a pair of 2x4s between the ground and the workbench with a rim-sized gap between them. You insert up to the approximate line of the bend and bend it back.

Many nicer modern aluminum rims are made of fancier, higher strength, less ductile material with thinner walls than in the past. It's important to understand that trying to bend around such rims is an entirely different proposition from what used to be commonplace. You would find it takes way more force (and likely took more to bend it to begin with), and cracking it either in the process or after a little riding would be a much bigger issue.


When I pedal the rear wheel is not turning

This sounds like either the freehub on the rear wheel, if you have the newer cassette style, or the freewheel, if you have the older thread on design, needs to be replaced.

These parts contain the pawls which drive the wheel forward when you pedal. If the pawls are broken, or simply not engaging the hub shell, you will pedal with no forward movement.

See this answer to the question What causes the noise that race wheels make when you are not pedaling?


Replace a Sachs Echo s with modern derailleur

Freewheel 6 or 7 speed wheels typically have no clearance problems there. The issue is likely being caused by rear derailleur hanger misalignment and/or the low limit screw being adjusted too far out. There are many questions about both.

Update post-image: The derailleur hanger is bent. Put the shifter in high position and poke a 5mm 3-way wrench or  L-wrench into the pivot bolt of the new derailleur. Reef it around to make the plane of the pulley centerlines appear parallel with the plane of the cogs. Re-adjust the high limit if needed, double check it looks parallel, and you should be good. Eyeballing like this isn't great for latte speed generation bikes, but it's fine for 5 and 6 speed. If you want to baby the frame you could have it done with a proper tool, which I'd recommend in most other non-emergency cases.


What should I do on the trail when I get mud caked in my chain, derailleur or cassette?

Mountain bikes weren't invented last time I had this problem.

Since you're already covered in mud, wipe much of it off with your hands. Be careful to keep fingers out of the parts that bite.

Use a stick where it's dangerous to poke your fingers, and get mud out of the derailleurs.

Depending on the kind of mud, and water availability

dunk the whole bike in a puddle or such.
use your water bottle to hose mud out of the important bits.
urine works too ...


Shimano Nexus Inter-3 internal gear hub stuck in second gear?

It's not clear if you've already bypassed the shift mechanism and attempted to shift directly using the shift pin - at least eliminate any possibility that the shifter is the culprit.

If you're already considering purchasing a new hub, there's little harm in pulling the old one apart to see if it can be repaired.  For some reason the Shimano TechDocs for that hub is missing, but I was able to find a mirror on the Vancruisers.ca site.  Looking at that it's not obvious what might be broken and failing to engage inside.

Note that there are some fiddly bits inside these hubs, you'll want to lay out a nice big sheet of butcher paper or a towel to work on, and take pictures as you pull pieces out so you can remember how they go back together.  Keep an eye out for any bits of metal shavings or chips of metal, that's usually indicative that you'll find a broken or missing piece inside somewhere.

If you'd particularly like to avoid rebuilding the wheel, I've had success also just swapping the internals on some internal hubs.


Dropped the Wedge of a quill stem in the head tube

Have you tried removing the stem so you have better access to the wedge? Often if you do that you can screw the bolt in and pull the wedge out, then reassemble it away from the bike.

The other approach is to again lift the stem out, remove the front wheel, then turn the bike over and push the wedge out from the fork side. If you have a front mudguard you will need to remove that too, but almost always the bottom of the steerer tube is open so you can get the stem bolt or another long, thin object against the wedge and push it out that way. You may need to hammer it a bit, so preferably use a long punch or spare bolt, rather than the stem bolt that you need to make it all work.


Using cyclocross tires for winter riding

Considering that you will be hanging up your bike come ICE time... I would say that CX tires can/would be a bit more confidence inspiring that a typical slick tire.  However, I don't think that a CX tire would be much better (and likely more expensive) than a nice inverted tread commuting tire like the continental Touring Plus or an equivalent.

Having commuted in an area like you describe... cold wet, more slush than snow, etc... I have had very good luck with inverted tread commuting tires and they can be (are) usually a bit more pleasant on pavement than CX tires.


Are these shallow gouges and imperfections on a new carbon fork steerer benign or serious?

I don't normally go around inspecting fork steerers, but I suspect that's highly abnormal and a significant cause for concern.
I don't clearly see torn fibers. If you did, that should mean the steerer got gouged in transit. Raoul Luescher is a carbon fiber repairer and consultant with extensive aerospace and bicycle industry experience. He describes some common manufacturing issues with carbon fiber. I think that the gouges might be related to porosity, which stems from improper compaction.
Basically, carbon fiber is a bunch of sheets of little carbon threads. These are immersed in resin, and then the assembly is baked at high temperature and pressure. The carbon plies and the resin are supposed to compact, i.e. come together. If are holes, i.e. porosity, this compromises the structure's strength. (Although normally I would suspect that porosity is inside the structure, not on the surface.) Alternatively, you can have areas that have too much resin, where the resin pooled and perhaps disrupted optimal compaction, or you can have areas with too little resin where some carbon fiber is left exposed. Either of these are bad as well.
Without a background in the subject, I can't be sure what caused these surface imperfections. They definitely look out of the ordinary for a new component.
I suspect you are correct that normal factory quality control would have caught this item and probably destroyed it. In theory, I have heard speculation that some people resell factory second items, like ones that were QC rejected. There are cases where factory seconds with only cosmetic issues get sold. To my knowledge, in the bike industry, these tend to be for accessories. For example, Spurcycle, which makes very high quality and expensive bells has an annual sale on what they call "Frankenbells". These have cosmetic but not functional defects. I haven't seen cosmetic seconds sold as new equipment in official distribution channels. It does seem possible that the rough spots in the steerer might only be cosmetic. However, that steerer is taking a lot of load, and I wouldn't chance it. This isn't a case of paint chips on a used carbon bike.


At what speed does Aerodynamics of a bike come into play?

As long as you are moving through the air, aerodynamic drag will account for some portion of total drag. Here is a plot that shows the relative contribution of aerodynamic drag vs. rolling drag on total drag for a rider at constant speed on a flat surface with the given CdA (drag area) and Crr (coefficient of rolling resistance). There is no magic threshold speed at which aerodynamic drag suddenly appears. Whether the amount of drag is important or significant to you will depend on your power and riding goal, but for this example roughly 25% of total power will be consumed by aerodynamic drag at about 10 km/h (or about 6 mph).


Does a bike helmet without chin straps make any sense?

Yes.  And no.  It makes some sense in that a helmet should fit snug enough to stay on on its own.  The chin strap's job it to keep the helmet on your head after the initial impact.  Were one to have some condition (a skin condition, stitches on the face or neck, etc) where the chin strap was extremely detrimental, one would be somewhat safer riding with a helmet simply missing the chin strap, than with no helmet at all.

However, barring some obvious condition, or a radical helmet design that doesn't require a strap to stay on after impact, a helmet without a chin strap makes no sense.


Curious about foot position on clipless and regular pedals when mountain biking

Clip-less (and before them, clips) came out of the road riding community where the emphasis is on power transfer and efficiency.  The most efficient position is the ball of the foot on the spindle (+/-1 a few mm). if you look at all early, and most modern, road shoes and cleats, its clear they are not suited to mountain biking and are designed for one task - the no compromise transfer of as much power from the rider to the bike as possible.

When MTB'ers started to use clipless, the advice remained "ball of foot" position, however by the late 1990's it was shown for MTB riders this is flawed  - that the stability and control offered with the foot further forward (In the extreme, spindle under the arch) provides a far better outcome when riding. How far forward/back is always a trade off between efficiency and control/balance. With flats, its not an issue - move your foot forward fro the gnarly downhill, back for an uphill grunt.

It took a long time for the  ideas of those pioneers to been widely acknowledged. Its only in the last few years (its taken this long) MTB shoes are being manufactured with the slots for cleats further back than previous models - I knew elite riders in the late 1990's who drilled holes and mounted their cleats behind the slots of shoes available at the time.

You will still hear a lot of people repeating the dogma that the ball should be over the spindle, they are very wrong, and the more extreme and technical the Mountain biking, the more wrong they are.

Another question that needs to be asked by every Mountain Biker who rides clip-less is 'Why, what advantage do they give over flats'? - the reason I mention this is if the roadies use clip less for one thing, improve power transfer, and the cleats back position we use on MTB is a compromise, whats the gain we are getting.


My chain came out of dérailleur frame, but gap seems too small, am I misunderstanding something?

To fix it, you don't have to break the chain. Simply unscrew one or both of the derailer pulleys slightly until you have enough space to get the chain through.


It is a matter of personal preference.  Triathlons generally have to be self supported (with some exceptions) so getting a full wheel swap like in Pro Bike races is not an option.  I run clinchers mainly for this reason as they are easier (for me) to swap out on the side of the road.  However, depending on your rim/tire this can still be pretty tough sometimes.

So if you are running tubs you would have 2 options:

Carry a spare tub tire & CO2.  You would need to be able to peel off the old tire, re-seat the new one, and re-inflate. This can be pretty hard.  Also, usually when you glue on new tubs at home you use fresh glue and let then set awhile to make sure they are well  adhered.  However, in this case on the side of the road you will be re-using the old glue or you could try tube tape (never used it personally).  This is a bit dangerous as now your tire is not as secure onto the rim and you risk "rolling" it off in hard cornering ...
Carry a sealant like Vittoria Pit-Stop.  This might seal & re-inflate your tire but if it doesn't then you are out of luck.


What size Mr. Tuffy Liner should I buy for my 24"x1.95" bike tires?

I'd recommend none. They're more likely to cause flats when installed improperly and increase rolling resistance and weight. You're better off purchasing Kevlar belted tires/ puncture resistant tires, or if you live in an area with thorns, thorn proof tubes. You should also make sure your rim tape is properly installed and your tires are properly inflated - with this, and the right tire choice, they should be unnecessary.

See also this question.

Also, 1 3/8" is not the same as 1.375 inches when sizing tires, necessarily (see Brown's law of tire sizing).

While I do not use Mr. Tuffy liners, I'd think the 26"x1.95" one with a bit of trimming is the way to go in this case if you still choose to use one.


Why is track cycling done counter-clockwise?

The UK National Cycling Centre FAQ (PDF) says:

Why do the riders go anti clockwise?
The Chariots in Roman times raced this way round, and athletic races and most other sports have followed in the same direction.

The Straight Dope says:

How do these things get started? I've gotten several letters asking why races are "always" counterclockwise, and I notice my fellow toiler, Omni magazine game czar Scot Morris, has written a lengthy treatise on the subject. Scot came up with the following list of counterclockwise phenomena: the Indianapolis 500 and other auto races, track and field events, Roller Derby, indoor bicycle races, horse races, speed skating, merry-go-rounds and other carnival rides, revolving doors, the chariot race in Ben-Hur, the customary flow of people around an ice-skating rink, the usual direction in which people spin Hula Hoops, the base runners in baseball, cable-operated model airplanes, and tornadoes and hurricanes in the Northern Hemisphere. ...
On the theory that there might be some dark link to our primeval past, Morris asked several distinguished anthropologists, but no luck. He morosely concludes, "the bias toward moving our whole bodies in counterclockwise cycles undoubtedly can be traced back to the right-handedness of our species and of every human society yet discovered, but how the one led to the other is unclear."

I didn't find it in the general UCI track rules, but it's in the track rules (PDF) of the UCI's World Cycling Centre in Aigle, Switzerland:

All riders must ride in an anticlockwise direction.


1991 (I think) Trek 850 MTB bottom bracket replacement. Maybe similar to 830?

Bicycle blue book says the 850 came with a BB-Lp26 bottom bracket, which was 68mm wide, 110mm spindle length, square taper. There are some new (old stock) on ebay, but I don't see why a newer BB-UN26 couldn't also be used (or any other standard ISO bottom bracket made for a 68mm wide shell, with a 110mm spindle).

I'd measure the BB shell and spindle width, just to make sure. Shell width is self-explanatory. You'll need to pull cranks to accurately measure the spindle width, and a caliper would be best. If you pull the BB, this info might be legible somewhere on the BB. I'd try pulling it before ordering a new one. Remember that the drive side has reverse thread, so clockwise to take it off. If it's from 1991, it may be seized pretty well. You may need to clamp a BB tool into a vise and use the entire bike frame as leverage to get it loose. I've had to do this in the past.


Counter-intuitive steering in crosswinds with hands off the bars

If the wind is from the left, you need to lean to the left to stop the wind blowing you over to the right; leaning left makes you turn left.


Best brake pads for long distance travelling?

The trick with rim brakes is to get ones with replaceable blocks. In that way you can setup the brakes once so that they have perfect toe-in (small gap at back so they do not squeal) and so that they hit the rim dead-centre (not at an angle, falling off the bottom or hitting the tyre). Then, when the brakes get worn you can simply replace the inserts and not have to start again with the setup.

Due to different places selling different stuff and having made an investment in your setup, it then becomes a matter of what are the most widely available inserts. In the UK this probably means the 'Aztec' brand. From my personal experience the after-market Aztec blocks and shoes are better than the cheeze-o-blocks that Shimano supply. 'Kool Stop' are also pretty good and widely available in selected markets.

As for choice of rubber, if you are undecided, what is wrong with dual compound? In that way you get durability and stopping power all in one.

I am not wanting to specify a shop/endorse a brand, however, here is what you should be looking for (as Googled earlier).

You can always try the different compounds to see what works best front/rear, what wears your rims out quickest (soft on rear is a good idea as rear rims wear quicker) and what fits your budget.

Moving forward, the replacement shoes are a double whammy of time savings and money savings. Not only are they quicker to replace, they are cheaper and you do not lose your settings.

And finally...

Enjoy your tour!


Gears shift perfectly when suspended on rack, but not on the ground?

While I'm not sure this qualifies as an answer, because with such questions there is usually a lot of guessing, your issue sounds like a flexing issue or a worn rear-hub.

The flexing could happen because of your weight (maybe fatigued frame? or just flexible) resulting in slightly changed geometry while riding vs suspended mount.

A worn rear hub could cause a wobbling or light tilting in the cassette while under load.

I would also check the cables while the bike is mounted on the stand and see that the clamps or the bike position (handlebars sitting at a hard angle, pulling on cables) are not somehow affecting the tension in the derailleur cable.


Bottom Bracket Size for Specialized Roubaix Elite C2 2009

It is best to remove your current bottom bracket to check, but as a rule of thumb, a triple (3 gear) front crank uses a 118mm. A double (2 gear) front crank uses a 109mm.


Dérailleurs exist not only to change gears, but to add tension to the chain as well. If you are noticing chain slack, and nothing else has changed or been replaced, the reason for chain slack is that the dérailleur has lost this ability.

This could be for a few reasons:

The dérailleur has lost some of it's 'springy-ness'. This can happen over long periods of time, but also can be indicative of damage, but is less likely.
The dérailleur has shifted positions. Some dérailleurs bolt directly to the frame, but some do not, and instead are positioned in the dropout. If you have this type of dérailleur, and recently removed your wheels, it's possible that the dérailleur has 'slipped' in the dropout.


Unlikely that the creak is in the bearings themselves due to needing re-greasing. It's probably at the press fit interface between the outer race and the frame.

Yes you can remove and refit the bearing units. If the BB shell is metal you can use grease or retaining compound to try to stop the creak.

Global Cycling network did a video on BB creak recently.


Dent in bearing cone, try to get a new one, or can I keep riding like this?

Anywhere there is a cone, there is also a "race" that the bearings sit in. The cone holds the bearings in place against the race. The picture you have posted shows the very definition of "pitted cone". As the wheel turns there will be increased friction when the bearings contact the pit. It will get larger and eventually the bearing will freeze in the pit. Even if it's just for a moment it will cause increased friction on the race.

Cones are very inexpensive relative to the cost of a new hub and the wheel building labor it takes to replace it, or relative to the cost of a new wheel. I would absolutely replace it.


key broke and stuck in U-lock with bike locked

If the key's broken flush and you can't grab it with a pair of needlenose pliers, you should call a locksmith or the police.

In all likelihood, they will just cut the lock with an angle grinder or a hacksaw with a diamond blade.

Though from the picture, it looks like the lock mostly is open and maybe a good hit with a hammer might dislodge the lock.


How do I install this Ribble endurance SLR headset?

In my experience I believe you should start with items in https://i.stack.imgur.com/so4gwm.jpg initially. Starting with the thinnest one first, in the direction facing down as you have them in your hand.
Lastly using this on the top: https://i.stack.imgur.com/cT9ppm.jpg
I would recommend using the Parktool Youtube page for more detail on Headset installation:
https://www.youtube.com/channel/UCzaZ1sPWEuZN-I8_XT6AH8g


Protecting yourself from briars / brambles / jaggers while mountain biking

I have used shin guards since the 1980s, growing up in Hawaii and now riding in Utah (both get pretty hot) and I found that wearing knee high socks help with the "heat" factor, but even then, as long as I am wearing shorts, I don't even think about my legs being warm.

I have been using the LizardSkin shinguards for about 15 years now and will continue to use them as long as I ride! (I am still riding the same pair, they are frekn very durable!)

For the shin-whacks nothing protects better, they have a V-shaped insert that virtually eliminates any hit. And if you want to ride without that layer of protection (or to wash it) you can take that insert out really easily. Even without the insert, it has a pretty durable front with some padding that would help with any sticks or whatever slapping you.

The neoprene has holes for ventilation but not really a big help, but the back gives me a gap of about 2 inches, and I have skinny legs. I have ridden a lot of downhill trails and they have helped a lot through the brush.

They even come down low enough to give your ankles some protection.


Loosen the handbrake in mecanical disk-brake

Yes, in your picture of the caliper you can see the barrel adjuster at the left side. Usually when mechanics set up a cable brake, they’ll allow about one rotation of space for loosening, and the rest will be available to tighten the brake as the cable stretches and the pads wear. So, it’s possible that you may not have enough adjustment at the barrel to make it as loose as you want. If this is the case, you could loosen the allen bolt clamping the cable and let out a bit of slack there.

You could also adjust the position of the static pad, which is the one nearest the wheel. This is usually done with an allen key from the wheel side, turning it clockwise to move the pad inwards and anticlockwise to move it outwards. You don’t want to back it out too far, though, as this might cause the rotor to start rubbing the caliper body when you apply the brakes. You should be able to observe this easily enough.

So, I would start with the barrel adjuster, then if you don’t get enough slack from that, let a bit of cable through the pinch bolt.


I crashed a couple days ago before the derailleur got bent and after the crash, I realized that when I try to shift to the big sprocket stationary, it sometimes will slip off and goes to the back of the cassette:

It sounds like the derailleur was already damaged in this crash, causing the shifting to be off. Perhaps the hanger got bent, causing the cage to point inward, throwing the entire shifting alignment in the direction of the wheel hub, thereby allowing the chain to derail from the largest cog. This is a bad situation if, additionally, the derailleur makes contact with the spokes.

In this situation, the lower limit trim screw won't help, because its action plays out in the pivot mechanism above the cage.

If you're prone to damaging your derailleur, consider installing a derailleur guard.


Failure statistics of carbon fiber vs aluminum mountain bikes?

I've read a lot of carbon fiber vs aluminum debates.
  Does anyone know where I can find actual failure stats for mountain bike frames? How many warranty repairs per year for each type vs sales volume, for example?

I'm reading this as a strength of materials focused question - carbon vs aluminum.

Summary:
For a properly designed, well made frame on a correctly assembled bicycle ridden in a manner that is not abusive (I know "abusive" is a relative term. A good frame should be over engineered to handle some abuse, say 80% - so I'm talking about the 20%) frame failure for carbon or aluminum is a non-factor.

However, warranty frame repairs/replacements data would be made up of:
- Material failures (that your question refers to)
- Manufacturing failures
- Flat out user abuse (the 20%)
- Incorrect assembly
- Damage during shipping
This statistic would not provide an accurate reflection of the merits of the two materials.

Generating reliable, comparable, standardized statistical data is expensive and tricky. There is no motivation for the bicycle industry to spend the money to generate this information or to share the data they have for many reasons. Frame design / styles change so frequently that even if the data were generated it would be outdated quickly.

We don't have reliable, comparable, standardized statistical data that allow us to compare specific frames or types of frames to each other we do strength of materials data that we can use as an indicator of the merits of the two materials.

Manufacturing Technology for Aerospace Structural Materials
Fig 7.2

  Composites do not corrode and their fatigue resistance is outstanding. Corrosion of aluminum alloys is a major cost, and a constant maintenance problem, for both commercial and military aircraft. The corrosion resistance of composites can result in major savings in supportability costs. The superior fatigue resistance of composites, compared to high strength metals, is shown in Fig. 7.2. As long as reasonable design strain levels are used, fatigue of carbon fiber composites should not be a problem

  The specific strength (strength/density) and specific modulus (modulus/density) of high strength fiber composites, especially carbon, are higher than other comparable aerospace metallic alloys.

From a strength of material perspective carbon is more fatigue resistant and higher strength than aluminum.
The materials are more than adequate to the task.
What matters is:
- Frame design
- Correct frame construction
- Correct assembly of the bicycle

In an ideal world (one without people who would cut corners making bike frames) you should be able to base your decision on the riding qualities of the two materials and your personal preferences.

So, select a trust worthy brand/frame maker and make sure your bike is assembled by a knowledgeable person and base your buying decision on your personal riding preferences.


You definitely do not want to ignore this. Loss of brake function is obviously dangerous.

At the very least, check regularly for further leaks in this area, before and after you ride. You mat find that the leak re-occurs after a while even though you cannot replicate it by squeezing the lever a few times.

You can of course have a repair shop look at it. Checking the hose for damage and replacing the bolt, olive and insert is probably a good idea.


I found the solution!

I've bought an alfine crankset with inner + outer chainring (FC-S501 GCx2) instead of of an alfine crankset with only the outer chainring (FC-S501 GCx1).

The problem being that the FC-S501 GCx2 is designed with a 49.2mm chainline and the FC-S501 GCx1 with a 42.7mm chainline.


Enduro or AM (All-Mountain) mate. They are more versatile, especially if you don't know if you are going to stick with DH.

These days, DH bikes only do one thing. If you don't know what that is or haven't been hooked yet, move the cash to an AM. A half decent AM bike will be a handful already for any novice.

Plus you can pedal back up and you will enjoy that more than waiting for adults to drive you back up.


How can I teach my capable 20-something friend to ride a bike?

I would go with the undersized bike method as Sheldon Brown recommends.

Basically, get a bike that's a bit on the small side (and has at least one brake lever) and remove the pedals (and maybe also the cranks), so that he can have his butt on the saddle (seat) and both feet firmly on the ground with knees slightly bent.  That way he can run with the bike under him.  You might be able to get a bike with a compact frame design (sloping top tube) and set the seat really low instead of having to actually start with an undersized bike. Starting out on a grassy surface would be a good idea, but a stretch of clear unoccupied pavement/asphalt (such as a parking lot) would work quite well, too.

At first he'll just use his legs and slowly get a feel for how the bike moves and balances, but as he goes faster he should be able to pull his feet up from the ground for a longer and longer time.  When he's comfortable with how a bike balances (able to coast and steer without keeping feet on the ground), put the pedals back on the bike.

Might a good idea to have him wearing a helmet and gloves, and maybe also kneepads, but only if they don't make him more nervous.  That way if there's any problems it might be less traumatic and more likely that he feels okay getting right back onto the bike. Any other protective gear would be overkill, you tend to catch yourself on your hands or hit your knees when you fall off of a bike.

After he's got the balance right, even with the pedals on, probably good to move to teaching a proper mount and dismount so that you can set the seat at the proper height.  On a cruiser or dutch style bike you can probably get away with keeping your feet on the ground when the bike is stopped, but in general you should mount by grabbing the brakes, putting one pedal at a 45º angle forward and up, using the pedal to step up to get onto the seat (and to get your other foot onto the other pedal), and almost simultaneously release the brakes so that the bike starts to move forward.  Dismount similarly (with brakes engaged and using one of the pedals to step off).

There's a longer list of skills he'll need to learn before riding safely on roads, but balance, steering, mounting and dismounting is a really good start.

Through all this, he needs to keep patient.  The simple reality is that it takes a while because you're trying to train your body into modifying its reflexes a little (so that you steer into a fall to keep from falling to the side).  If you try to think your way through balancing on a bike you'll fall over a lot because thinking is too slow, you need to retrain reflexes.


What is the deal with the new weird Gazelle chain case design?

Found an English Language site that explains it. From

http://www.cycle-heaven.co.uk/bikes/brands/gazelle/gazelle-chamonix-c7-women-s-2015/

  All Chamonixs feature Gazelle's innovative transmission design with a
  chain tensioner inside the chain case. This keeps the chain always at
  the correct tension, needing less maintenance and giving a quieter
  ride. The frame is able to use vertical rear droputs which makes wheel
  removal and puncture repairs much easier.  We also think it gives the
  bike a more streamlined look.

It's called the FlowLine chaincase - here's a picture of it:

So it's not what you think. I can't say whether it's a good idea or not, but it seems at least a plausible solution for a City Bike.


First of all I’d fix the saddle position. A low saddle will decrease your power output and can cause knee problems. As a rule of thumb your leg should be fully extended with your heel on the pedal in the 6 o'clock position.
Keeping the handlebars low or even lowering them further will generally improve your aerodynamics.
Make sure the tires are inflated to a relatively high pressure (depending on your weight and road surface, probably around 4–5bars) to reduce rolling resistance. Make sure the chain is lubed properly to reduce friction.
Wear tight fitting clothes to improve aerodynamics.
Regarding turns: Here I disagree with Adam Rice, a lot of turns will certainly decrease your average speed, especially if you have to brake. Good brakes and technique can allow you to brake stronger and therefore later, thus improving your average speed.
Since it sounds like you are using average speed as a benchmark of fitness or power: It’s relatively useless for that, even if you only use it to measure your own progress. Even on the same roads different wind or traffic conditions can cause a lot of variation.


Cito bicycle history / old steel bike identification

That is a unique-looking bike.
The seat stays appear to be bolted on top and bottom, which is how a PO was able to fit a belt without cutting the frame or using a split belt.  That it has track ends rather than a dropout suggests this might have been a track bike in its early years.
However track bikes generally don't have brakes for track use.  It is possible the same PO fitted the front hub brake (wise move) and uses the fixed gear rear hub as the back brake.
The belt drive system is a relatively recent addition, and I guess this frame was selected because of the rear stays.   I can't find a "coronado" crank with belt drive, so its possible this combo is an aftermarket replacement of traditional chainrings with a single drive belt spindle.
The rear hub appears to have a "pull chain" hanging from the side and tied by string.  This could be a way of making an IGH into a single speed ?  Seems dodgy to me, I'm not sure if an IGH would like being locked up for rear braking, or more likely this bike only has a single brake and the rear coasts.
The head tube angle looks very "reclined" compared to more modern designs.  I bet this bike is easy to ride no-handed due to the slack angles.
Obviously the handlebars are a replacement - this bike would have had drop bars or track drops originally.  The saddle is definitely much newer too.
Lastly, the tubes appear to have a Woods or Dunlop valve.  These have become less common globally, other than China and the Netherlands.  I would also suggest looking closely at the tyres for dry rot and cracking, for safety, they don't look new.
All in all, sweet bike and you'll enjoy riding it.   If it were me I'd fit a rear brake, connect the IGH to a shifter, and possibly go back to drop bars.


The rust is only cosmetic surface rust. I would ignore it.
In future, don not use vinegar as it is quite acidic. A proper degreaser will clean the chain and running gear without causing rust.
Oiling the chain is essential after cleaning, mainly to provide lubrication, but also the oil prevents rust. It is best to use a proper bicycle chain lube, as (what I think of )
a light oil is too light to provide the lubrication needed (much better than nothing if its all you have available).


Front and rear derailleurs have no interactions, so there's no concept of direct compatibility between them.

Rear derailleurs have to be compatible with the rear shifter, cassette, chain. Front derailleurs have to be compatible with the front shifter, crank and chain. Obviously there is some interplay between the front and rear drivetrain.

I don't think that a 10 speed triple derailleur will work well with a 9 speed triple shifter and crank. Shimano changed actuation ratios (ratio of cable length pulled to cage movement) on 10 speed MTB groups.

I'm not sure that an old M980 derailleur from 2010 is really an upgrade anyway. Any benefit of a better front derailleur would be completely masked by the performance of the lower level shifter. Safer to get a current Shimano 3x9 Alivio or Acera front derailleur replacement.


Does never using the easy front gear give a better workout?

It is not necessarily "good" for your workout. If you drop into the 'easy' gear, you obviously have to pedal faster to maintain your speed. Going at a slower cadence in a higher gear will just trash your knees after awhile.

Select the gear that yields a similar cadence as when you are riding on the flats, while maintaining a similar energy expenditure.

Your chain rubbing problems should be solved by adjusting your derailuer and properly maintaining your bike.


Why aren't average speeds computed over distance?

This is an interesting point of view. Let's unpack this a bit.

Assume I have a ride that is 10 miles of flat, 10 miles of ascent, and 10 miles of descent.
On the flat I maintain a constant 20 miles/hour.
On the ascent I fall back to a constant 10 miles/hour.
On the descent I maintain a constant 30 miles/hour.

My average speed for this would be:
(10 miles + 10 miles + 10 miles) / (0.5 hour + 1.0 hour + .33 hour) = 16.39 miles/hour

By the proposed calculation I would have:
(100 tenths/mile * 20 miles/hour + 100 tenths/mile * 10 miles/hour + 100 tenths/mile * 30 miles/hour) / 300 tenths/mile = 20 miles/hour

If I had an average of 20 mph I should be able to complete the course in 1.5 hours.  The trouble is that the course would actually take 1.83 hours to complete at the actual average of 16.39 mph.  I know it hardly seems fair, since by all rights you did the vast majority of miles at 20+ mph.  The caveat is that you spent by far the greatest amount of time at 10 mph.


Are there any major outstanding recalls of bicycle parts?

Places to Find Information on Recalls and Safety Issues

United States

The US Consumer Product Safety Commission is the organization responsible for recalls and safety issues in the US.
Recalls.gov
To report safety issues, SaferProducts.gov
A convenient listing, Consumer Affairs

New Zealand

https://www.recalls.govt.nz/


Vary your cadence during your commute.High cadence (90 - 110+) will train the heart. Low cadence (60) in a Higher gear will give your Legs Back and Arms a good workout.Dont forget to do some regular stretching esp on those big glutes.


Accidentally clipped into Shimano PD-A530 BACKWARDS -- won't release!

You are right that  these cleats are "multi-release" which should help.

So try twisting the shoe straight up, but given the cleats are backwards you may need to lift/rotate the TOE end of the shoe not the HEEL end.

Good luck!


It's pronounced without the K, see-ree-um.

Source: a bunch of bike-shop-workers who seemed to know their wheels ;)


Fastace is a maker of bicycle components. That looks like a freewheel with one belt drive sprocket instead of 5 or more chain drive sprockets.

See the Terminology Index for a description of the difference between freewheel and freehub/cassette systems.

The belt drive freewheel should be removable with a four tooth removal tool (see the Park Tool video below for tool selection guidance). You'll then need to get inside the freehub to clean and re-lube the bearings and racheting mechanism. I believe that's done using a pin spanner to unscrew the rings with 'KENGMIN fastace' written on it. See the RJ the Bike Guy video below for a idea how the might be accomplished - your freewheel might be a bit different, but it gives you and idea of what to expect.

As an aside, that's an interesting kids bike. Not sure I like the radial lacing of the rear wheel though.


A rim is a piece of aluminum extrusion, rolled and joined into a hoop.

There are several types of joints used.

Rims can be pinned together using a piece of metal at the seam to hold the alignment.

Or the seam can be aligned and welded. This is the strongest method. Welded rims used to have a small bump at the seam from the welding process, which would wear smooth from brake use.

Someone came up with the idea to weld the seam for strength and then machine the braking surface smooth, which is the strongest and best kind of joint possible on a rim.


Super hard to measure without a power meter. But you could approximate it using various web resources.

https://www.bicyclerollingresistance.com/ lists the best fatbike tyre as a "Schwalbe Jumbo Jim Liteskin PaceStar" with 36.9 W of rolling resistance.  The best road tyre is a tubular at 7.7W with most clinchers (ie normal tyres) under 20W per wheel and averaging 15W.

http://bikecalculator.com/ doesn't know about tyres specificially, but if you put 200W in and compare that with ~15W per wheel for a road bike and 36.9W per wheel for a fat bike, then you're effectively comparing 170W on a road bike with 130W on a fatbike.

Assumptions - 100 kilo rider (dressed)

170W on a 15 kilo road bike with hands on hoods, clinchers, over 10km will take 20.8 minutes for a flat road or 122 minutes up a 10% grade

130W on a 18 kilo MTB bike with hands on bartops, clinchers, over 10km will take 24.3 minutes for a flat road or 164 minutes up a 10% grade.  I feel a fatbike would be even slower than a MTB.

This is excluding the aero differences between bikes too.


You can't really burn "tummy fat."  Your body has an order that it will store fat in and it will lose fat in the reverse order.  You can lose bodyfat, but it goes away in the reverse order that you put it on.  You can make it appear that you've proportionally lost more weight in your tummy by building up the muscles there.


Life metrics for v-brake pads (time to replace, time to change)

It's difficult to give a general estimate on how often brake pads should be replaced, as conditions vary. (Including how often you ride, temperature, humidity, do you store your bike in direct sunlight, how old the brakes are, etc.) If it looks worn, replace it.

Adjusting brake tension via the screw nuts on the handlebars is the best way to make adjustments. As brakes wear down with use, you will need to make these adjustments to compensate. Needing to do this ever month or two seems within the normal range for how often you use your bike.

Another factor to keep in mind is that cables will stretch with use. If the screw nuts on the handlebars are at their limit, you will need to loosen the nut holding the cable at the brake to adjust the cable. (When you make this adjustment, make sure to reset the screw nuts on the handlebar).

Your recently purchased brake pads seem fine. I've found that a manufacture will include the housing even if it's not needed. Just be sure to toe-in your brakes slightly, and reset the handlebar screw nuts (and cables) as needed.


Not finding the right tension for my threadless headset

I figured out what was causing the problem. I had used the compression ring in the place of the crown race. I did this because I lost the crown race and the compression ring looks similar.

FYI crown races for threadless headsets aren't standard, if you need to replace one you have to get one that matches your make and model.


Brake squeal on caliper brakes despite usual solutions

Replaced brake pads with new ones.

Try a different brake pad material. Don't just blindly replace brake pads with new equivalents of what you currently have. Try a different material.
I used to prefer Kool Stop Salmon colored pads on all bikes I owned. However, on one of my bikes, Kool Stop Salmon pad squealed in the front cantilever brake like hell. I even tried a dual compound Kool Stop pad (consisting of half Salmon and half black compound) but didn't help.
The solution was to use the standard Shimano S70C pad in the front attached to the Shimano brake pad holder.
I don't know if the cause was the different brake pad holder (the Kool Stop pads were integral design, not separate rubber pieces put into a holder), or different brake pad material.
Yet, this Shimano holder combined with S70C pad solved the issue with me. Unfortunately, the Shimano pad does not resist grit intrusion in as good manner as the Kool Stop Salmon pad resists, but it's acceptable.
Keep trying! Experiment with different kinds of brake pad materials and holder designs from different manufacturers.

The only remaining thing I can think of is the front wheel has a very slight wobble, presumably my next step would be to try and true the wheel a touch

If the squealing is continuous around the wheel rotation and not intermittent, fixing a very slight wobble in the wheel probably won't help. Squealing brakes cannot magically know whether:

There is a wobble 180 degrees away, so they should squeal
There is no wobble 180 degrees away, so they should not squeal

The point is that brakes are local. A wobble is local too, and thus wobble will squeal only at the wobble, not all around the wheel. Wobble-dependent continuous squeal would be spooky action at a distance.


How many lumens (lm) should a front light have?

A front light needs to have both enough lumens (brightness) and have those lumens pointed in the right places - dictated by the reflector and lens. It also needs a battery (presuming its not dynamo powered) to last the length of the ride with some reserves. Addition things to consider are ease of install and removal from bike and mounting location, and battery size ( do you need to charge after every ride, or once a week?) .

More Brightness is easy to cheap to achieve and easy to sell (Mines bigger than yours), and very easy ti lie about "6000lumen". Reflector and lens is design is hard to achieve and hard to sell "Its not the size, its what you do with it that counts"

There are plenty of cheap Chinese lights on ebay that will do a good enough job for under $50, closer to $20 - they work on the "Bigger is better". For a better light in every way, you need to move away from these to a brand name light costing much more to something that has some brains behind the design.

My budget dictates cheap Chinese lights and accepting the poor light distribution  My $25 lights claim 1200 lumen, probably have 600 and its all pointing to a high intensity spot with very little out to the sides.The battery is claimed at 4400mAH, I have measured it at  2000mAH, but do get the claimed 2 hours on high.

As already suggested, refer to the BikeLightDatabase,


How to fit BB bearings to install Ultegra Crank on road bike Wilier Cento 1

Edit: frame is BB94 not 386

Your hollowtech bb wouldn't work as you correctly identified you'd need BB386 pressfit bottom bracket, (see exploded diagram below)you'd just need to make sure the bb you choose is compatible with your chainset and yes ideally you'd need a bottom bracket press to fit this or alternatively your lbs would fit it.

You'd need something like a bb reducer spacer kit to change your bb from bb386 to bb30...
bb386/30 converter kit

and then the pressfit bb30 bb that will accept you ht2 ultegra cranks.
FSA Reducer

bb press tool
See Also... How to service a bb30 bb


Is 32km possible to ride with my body condition?

32km per day is a lot for some one who is out of shape.

I added the [commuter] tag to your post. If you click on it, you'll see hundreds of posts about commuting. Some are like this one, so your question may get closed if it's a duplicate.

Since you know you have health issues, the conservative advice is to discuss your plan with your doctor.

If it's medically ok to go ahead, then start by riding to work one day, then ride home the next day, twice per week. You will need to store your bike somewhere. Gradually build up, until you can ride both ways every day.

So, I agree with your friend, but you can build up to it.

Here is a similar (but not really duplicate) question: First time commuter needs advice. A couple of different answers will be helpful.


On a brand new bike I would expect the seller to take responsibility for this and sort it out.

If this is not an option, the usual way to true a wheel without a stand is to turn the bike upside down, or remove the fork and hold in a vice, attach a zip-tie to one of the fork legs and use that as a guide.

The procedure is spin, find largest deviation, pull/push that towards the centre, repeat ad nauseam. There are guides all over the internet on the actual process of truing.

Do not just loosen the whole wheel. Getting a slightly wobbly one straight is easier than building one straight from scratch.


Replacing pneumatic bicycle tires with Honeycomb Hole non-pneumatic tires

Most likely the 24" 1 3/8" tyres will not fit on you bike with 24" x 1.95" tyres. While the inch diametre is the same, decimal and fractional number usually mean different standards for tyre sizing.

Sheldon Brown provides tables with sizes. Here is an excerpt:

24 x 1.5-24 x 2.125 | 507 mm        | Juvenile mountain bikes, cruisers

24 x 1 3/8          | (E-5) 540 mm  | British Juvenile, most wheelchairs;
                                      common on women's utility bicycles in Japan.

Please check if your tyres provide also an ETRTO number, such as 50-540. ETRTO numbers give the nominal tyre width followed by bead circle diametre, also in milimetres.

If the larger number matches, the tyre is intended for a rim of the same size.

At that point you have to check if rim and tyre width are compatible and if the tyre clears the frame and brakes. Both are usually not an issue when the sizes are about the same. Unless you have very little tyre clearance with your present tyres already.


It used to be easier to tell BSOs from "real" bikes, but now the technology is changing so rapidly, and it's much harder.

On a bike older than about 20 years, one would first look at the frame, in two places:

The joints.  Better quality frames would be "lugged", with the steel tubes brazed into fittings (called lugs) that secured the joints.  Cheap frames would just have the tubes welded together.  (Welding, as used then, would destroy the thin, high-strength steel used in better frames.)
The dropouts.  Cheap frames would have rear dropouts that were quite clearly just stamped from sheet metal, while the front dropouts would be similar, or would simply be slots cut in the ends of the flattened fork tubes.  Better quality would use forged dropouts.

These days the dropouts are still a tell, but not nearly as reliable as before.  And frames are often made of materials other than steel, and even steel can now be welded, using a rapid-weld process originally developed for aluminum frames.  (Though a good-quality lugged steel frame is still a thing of beauty.)

Other than the frame, the most obvious identifier of low quality is a one-piece crank.  This was true 20 years ago and is still true.

Well, I'll take that back -- one more thing:  Twist shifters are highly suspect.  They are cheap and have an extraordinarily high failure rate.  There presumably are some good quality twist shifters, but they're the exception.

Make that two more things:  With a multi-speed bottom bracket, check the material used to make the chainrings.  Very often BSOs have steel rather than aluminum chainrings.  A better quality bike may have a steel "granny" ring, but the others would be aluminum.


I think you'll struggle to find panniers that will fit that rack with the trailer attached.

It's just possible a seatpost mounted pack would work, but the clearance looks tight.


As long as you have a ten speed chain it should be fine.
Presuming this is FC-M675 or FC-M677, use the 8.5mm bolts from the inner ring. The 7mm ones from the outer are below Race Face's recommended bolt length.


As far as I know, these are the only possible consequences:

Your tire may rub on your frame.
You might have trouble getting your brakes to work (assuming you have rim brakes).
Your bike might run a bit sideways if your rear wheel is not centered on the frame. This can make riding no-hands difficult, because the bike wants to drift to the side.


Your frame is most likely intended for 135mm spacing and measures 134mm either because of manufacturing tolerance or because it was bent by using too narrow hub. The angle difference between 130mm and 135mm hubs is about 0.4 degrees, which is not really visible to naked eye.

135mm would be the way to go, but there is no immediate danger from keeping using 130mm either.


This image has kicked around the net for a while - IDK what the original source was:

Otherwise, I second the guidance and link provided by @fady.