I use a tool made out of a steel wire clotheshanger to squeeze the two pins together and open the link.

Also, that one hanger turned into three tools: the link opener, a tool to hold the ends of an open chain together, and one to hang the cleaned-and-drying chain from the tree over the driveway.


Is there a standard equivalent for effort between distance and elevation?

If you really want to measure how much effort you're putting in, you should look into getting a power meter. It measures the actual wattage you output, and can therefore be used to calculate total energy output. However, they are quite expensive.

The other option is to get a heart rate monitor along with cadence and speed meters which together can give you a reasonable estimate of how much energy you used.  This ends up being much cheaper than a power meter, but is less accurate.

These are the preferred methods if you a really want to track how hard you are training. This is because many things can effect how much effort it takes to cycle such as hills (like you mentioned), but also wind, your body position, and the road surface itself.


Is it normal for a presta valve to unscrew into two pieces?

The correct answer is yes and no. There are in fact two types of Presta valves: One where the core can be removed. Those are often used with tubular tyres so that the inner tube can be filled with a sealant (latex) fluid. Some higher quality tubes also have removable core valves for the same purpose. Normal and cheaper tubes have Presta valves where the core cannot be removed.

There is a special tool to be used for handling the core although like @Michael said the (careful) use of pliers also works.

Another reason for a removable core is the possibility to use valve extensions with high rims.


kid's bike rear brake not having stopping power

Sadly braking at the rear wheel is relatively poor because of a combination of factors.

Kid's hand strength - your average 4 year old can't squeeze the lever as hard as a larger rider.  This affects braking at both wheels.
The brake lever's pull ratio is also often sized for a full sized brake so it has to move through a certain angle to pull enough cable to actuate the brake.  For a little hand the lever can be scaled down, but it still has to pull enough cable, and the brake calipers are not scaled down.  Notice you didn't have to fit a "kid sized" caliper.
Mass - the rear wheel's brake is never as effective as the front wheel's brake because the system's center of mass is higher than the axles.  As the brake bites, the rear wheel becomes unweighted, so is more likely to skid.
Cable friction and a longer run of outer - You've already addressed these.

You will generally find the small 12" wheel bikes to have a backpedal or coaster brake because kids have better leg power than hand power.
As such, kids can do "mad-skidz" with a coaster brake but not a hand brake.   Part of this is the body motion required to stomp on the rear pedal naturally weights the rear of the bike, while I've never seen a kid consciously do the same while hand braking.

You might try roughing the braking surface of the rim very lightly with sandpaper.
As an adult you should be able lock the wheels easily while wheeling the bike around while you walk beside.
Another test option is for you to try riding the bike and test the brake function.  If its really way small, you can sit over it and keep your feet on the ground rather than pedalling.
Do basic checks, are the brake levers bottoming out on the handgrips?  Are the wheels true ?  Can you take some of the gap out so the brake pad sits closer to the rim, but does not rub.
Good luck !   And remember, they grow up fast and will be on a bigger bike in short order.


What kind of road tyres should I go for winter commuting?

I used Swalbe Marathon's last year without too many problems. As has been previously said, the narrow (25mm) tyres do help cut through snow, but when you are on ice nothing is very good.

I liked Continental Top Tourers previously.


Problem getting to big ring with XTR M960 Shift Lever

Finally found the right combination of Google foo to find what I was looking for.  This Youtube video breaks it down that old grease in the shifter is keeping the teeth from catching.

By spraying WD-40 into the housing via the inner cable hole.  Let it soak a bit, and work it in via shifting up and down.  It may take a few minutes, as mine took 5-10 minutes and a couple of treatments but finally it started getting the big ring click.

After the WD-40 is dry, then lube the inside of the shifter with a regular lube to keep it operating well.


Just bought a Nicol bike and not sure who makes them

the person who founded ibis bicycles is named Scott Nicol.  Ibis is known for mountain bikes so maybe it is an early pre Ibis by Scott Nicol or maybe not.

more pictures might help

The braze at the seat post looks like a hand braze, but its hard to tell from the picture.  It might be a hand built frame.

I would send an email to ibis and ask. Their web site says they have around 20 employees. It might be worth something to them.


It’s possible the shifter mechanism has some material in it that is obstructing the proper operation, maybe a bit of wire from the cable, maybe dirt or grit. Unfortunately it may also be that something broke in the shifter.
You’ll have to systematically track down the issue. I’d start by removing the cable completely so you can check for damage to it.
Next, work the shifter without the cable installed just to check that the leavers are not jammed.
If the cable was not damaged re-thread it through the derailleur and out of the housing on the handle bar, or even the back of the shifter without going through the housing if you can manage it. Make sure the cable head is seated in the shifter properly. Put a little tension on the cable and work the shifter to check it’s operation. You may be able to get a better sense of what’s going on with it.


If your bike was a 2019 (which I’m assuming it isn’t) it would be an H30, as that’s the current model that has an aluminum frame and 105 groupset.  It’s probably either an H30 or the equivalent from 2018 or earlier.

when trying to identify a recent bike, If the manufacturers’ web site has an archive section, you can go through it looking for a match WRT frame material, colors, major components etc. I’m writing this answer in a mobile device so I can’t see if Orbea’s main site has a link to an archive section.

If you have good guesses for model and year googling for images or past reviews will often yield a hit.


Can I convert a rim brake wheel to a disc brake wheel?

The hub for a disc brake wheel has the mounting for the brake rotor machined into the left side, and has shorter spokes that side to make room for the brake.

If the eBay wheels are for rim brakes, they won’t have these disc mount features out the box. If the spoke counts match and are sufficient, you could theoretically rebuild the rims onto disc specific hubs, but at best you would only be able to reuse half the spokes, quite possibly you’d need to replace the hubs and all the spokes.

It’s not that this can’t be done, but it would probably be less economical in time and money than paying return postage or fees for listing the wheels again on eBay yourself to then buy the right set. You would also have to sell the unwanted hubs and spokes to recover the money sunk into those. It would certainly be more hassle!

Great point from @Rider_X that disc wheels can require higher spoke counts, so that may take the whole exercise off the table anyway. Rim version of these wheels are 20 spoke front, 24 spoke rear, while the disc version is 24 front, 24 rear. In general terms, not having enough spokes on the disc (or any) wheel would be a bad idea.


Why such a tiny difference in crankarm length?

MTB crank arms usualy come in 165, 170, 175 mm. Some people (usually PROs) can have access to more fine grained lengths (e.g 167.5) or ever smaller sizes such as 160mm.

The reasons for such "micro-optimization" are:

clearance

Today MTBs for trail riding need to have a lot of front and rear suspension and very low bottom brackets. This makes it easier to hit rocks with the pedal and that is not desired.

Also note that ground clearence problems are in addition being solved with very thin pedals (thin pedals also solve other issues).

So, saving 5mm from the cranks and 5mm from the pedals may not seem enough but it can actually reduce the times you hit the ground.

Note that downhill specific bikes will usually have 165mm cranks.

proper fit to rider height

A short rider (with short legs) will pedal more efficiently on a 170mm crank than a 175mm one.

Thus small MTBs usually ship with 170mm and medium ones with 175mm.


What's the deal with the axle of my wheels? (or, why is one gear so much smaller than the other?)

Ok, I googled that funky MegaRange 14-34 (first picture) and it appears to be a 7-speed threaded freewheel.  The second example is a bit harder to make out but it appears to be a modern cassette+freehub design, not sure how many sprockets.  The two designs are incompatible and use different hub styles.

The freewheel design includes both the sprockets and freewheel (the mechanism which lets you coast) as one piece, which screws onto the hub body.  This is an older design and is limited to a lower number of gears, typically 7 or less.  I'm not sure of any clear advantage, other than it's easier to replace the freewheel in this design.  It's been a long time since I had one of these.

Most modern hubs use the second freehub design, where the hub includes the freewheel mechanism.  The sprockets come separately as "cassettes" and can be slid onto the freehub; a locking ring (black in the picture) holds the cassette in place.  Cassettes make it easier to change out a worn sprocket set, or to switch between different sets for different conditions (e.g. one for flat terrain, another for climbing).  Because the cassette widths are standard, you can often upgrade to more sprockets without changing the hub (although you still need to upgrade the shifters).  The tradeoff is that to replace the freewheel you'll end up replacing the entire hub.

For more details (with pictures), check out Sheldon Brown's site.


Are road bikes durable for use on roads full of cracks and potholes?

I know the roads around Reading very well. I commute 10 miles into Reading every day. I also ride a lot at lunchtime. I probably ride 5,000 miles a year in Berkshire. I ride a Bianchi C2C road bike which has an aluminium frame and carbon fork. Any modern road bike of reasonable quality will be fine.

The roads around Reading aren't that bad. I've never had a problem with the roads damaging my bike. That said, I do take reasonable care, including:

Avoiding the really bad bits by looking ahead and steering around them. Be aware and cautious of traffic when you do this.
Hitting rough bits lightly. Bend at your elbows and knees, and absorb the shock. Don't let the shock transmit up to your body as the weight puts stress on the frame and wheels.
Not riding up and down raised kerbs. If you have to cross a kerb, get off and lift your bike.
Only riding asphalt surfaces (i.e. roads or good cycle tracks). Don't ride dirt or gravel routes, such as the one alongside the river.

If you want to check out some bikes, I'd suggest AW Cycles in Caversham (I have no affiliation with them other than as a customer). They have a good range and are knowledgable and friendly.


Will a newer Shimano series cassette be easily interchangeable?

The spacer is required for 11-34 cassette only, same story as CS-R8000 11-34. The 34t cog hangs over freehub body, which allows to use the good old 8-10 speed HG freehub body. For a note, Shimano MTB 11 speed cassettes do not require 11-speed specific freehub body either.

  My question is, will the spacer requirement on the new cassette with
  my road bike force me to mess with my rear derailleur indexing/etc.
  when I swap the wheelset/cassette?

To be honest, I did not run this cassette, but it would make no sense to change offset just because it uses a carrier spider instead of cogs riveted together. At worst, you'd have to put a thin spacer under the cassette when swapping it between 11-34 and smaller range options like 11-28.


Best way to mount a big backpack to rack?

I would suggest splitting the weight in half and putting it low on your bike for stability.
Here is my daily commuting configuration (2 matched 6 gallon plastic waste baskets mounted by hose clamps to a standard bike rack.) (Your emptied backpack could be rolled up and placed on top if you need it for off-bike use.)


These look pretty far gone, as suggested. Lucky the rotor isn't scored, or that would cost more than a set of pads.


How often do you need to lubricate alloy seat posts

No they won't. It is often enough to lubricate once when the bike was built unless it is used/kept for a very long time. Especially if the bike is kept in a dry place. It is not necessary to lube it once a year. The lube stays there and protects the interface for a long time. If you pull a bike that hasn't been used for ten years from a shed, many things could be seized but even then seizing of the seat tube is far from guaranteed. It is even unlikely if it was well conserved before the storage.

Interface of two different metals could change it due to electrochemical potentials and rusting. I assumed aluminium alloy on both sides or steel on both sides.

Just do it the next year or when you get to your bike.


how do you remove rear wheel on scott genius 920?

I couldn't find any images just a description. Apparently it is similar to a conventional skewer. The difference is, the skewer is removed to drop the wheel out of the frame. The nut that typically is not removed is captured in the frame. Some owners have complained it is difficult to line up the skewer with the "nut"


Rather than any complicated method or products, I do the following:

Take it with me when I shower.
Lather up hair with my preferred shampoo.
Loosen straps and fittings, place helmet on head and move and squish it around a bit to distribute the shampoo.
Rinse
Repeat.

Shampoo or body wash works great.  Then I just clip the straps over a line to hang the helmet to dry.


Rim brake on front and disk brake on rear

With no disk brake mounting lugs on the frame you cannot mount disc brakes. There are bolt on adapters but I personally would not trust them. Additionally you would need a disc compatible hub which in reality means a whole new rear wheel.

You should check that that the wheel rims are compatible with rim brakes. There appear to be reflective stickers where the braking surface should be.

I always advise buying the bike you want, not a fundamentally different one hoping you can convert it. The easiest path for you might actually be to sell this bike and buy a single speed with front and rear rim brakes.


What and where is the weeping port on Shimano MTB brake levers?

From my understanding, that port is a pressure compensation port. When the oil level changes because of pad wear, temperature, or a leak, air will enter through that port to balance the reservoir’s pressure. The oil is kept sealed by the membrane, which you might have torn due to overfilling.
There’s a small port in the side of the master cylinder that connects the reservoir to the cylinder. When you actuate the lever, the piston travels past the port, allowing the system to build up pressure. When you release the lever, the port opens up again and does any necessary compensation.


Using cheap bike computer as a cadence indicator, possible?

This has been done before in pretty much the manner you're describing (and its basically the same way that a decent number of commercial cadence sensors work, e.g. Garmin GSC10, which attaches a magnet to the pedal arm and uses the same type of sensor at the wheel).

An example of someone doing this is this instructable. Basically, the guy attached a bunch of magnets to the crankset's granny ring equally spaced due to how his meter read out (*), and bolted the sensor to the downtube near there.

The main challenge is getting the readout to be readable on your bike computer and also aligning the magnets + sensor.

That being said, Bontrager among others sell ANT+ cadence+speed sensors for around 30-40 USD, so you might not be saving all that much by using this if you already have an ANT+ phone/bike computer.

(*) Assume the bicycle computer is programmed for a tire circumference c (which will be set within some range of values prescribed by the computer manufacturer). Each time a magnet passes the sensor, the sensor counts 1 circumference of tire worth of distance. by putting n magnets on the granny ring (which is the closest and therefore easiest to trigger the pickup), each revolution of the crankset reads nc distance. By setting the tire size on the computer to satisfy cn*1 rpm= 1 km/h, the readout of the computer in km/h will be the cadence in rpm.

The main problem is that your computer probably won't read past say 100 km/h. So, you can do something like set circumference of tire to satisfy  c*n*2 rpm= 1 km/h which would give you half the rpm as a readout, or similar.

You also need the magnets to be spaced far enough apart (or of suitable strength) that the sensor (most likely a reed switch, less likely an inductor or hall effect sensor) can switch on and off to register each of the magnets.


Why would non-drive side leading spokes break?

Spokes generally break when they are not tensioned enough, because they can then cycle from being taut and being loose as the wheel rolls, and because of this they fatigue and fail. Specifically, as the wheel rolls on the ground, when a spoke is pointing up, away from the ground, it does not carry any of the bike and rider weight and is tensioned, but when it is pointing down, it carries weight and this counteracts its tension, so an insufficiently tensioned spoke will lose all its tension and become loose. This taught-loose fatigue cycle repeats every wheel turn, which quickly adds up to a lot of cycles and breaks the spoke. As the non-drive side spokes of the rear wheel are less tensioned to begin with, it makes sense for them to be more prone to this issue, and the point at which a spoke breaks is usually at the rim, because that is the location of the spoke threads, which cause stress concentraction (they can be thought of as little cuts in the otherwise smooth spoke surface).
I have seen same wheels, one properly tensioned and one not (easily checked by squeezing the spokes together by hand), behave completely differently becasue of this. The tensioned wheel was virtually undestructible, whereas the loose wheel had its spokes break all the time. The owner of the loose wheel thought his wheel was junk, when in fact all he needed to do is tension its spokes properly. The moral is, when you buy wheels, check that they have been tensioned properly out of the factory, it makes a world of difference.


Where to get gear shifter for 31.8mm handle bars?

22.2 mm (7⁄8 in) is the standard diameter for the brake, shifter and grip area of MTB handlebars.

I think you bought a bar that was designed for bar-end shifters only. Easiest way out of this is to swap the bar for one that allows shifters and brakes to be mounted on the area between the stem and forward turn.


How to encourage people close to me to become cyclists?

Set a good example

In my experience, this is the baseline for almost any personal cycling advocacy.

Be available to help

Make it clear that you're available (but not pushy) to help any friends/family with cycling.

A challenge to get them in the habit

My regional bicycle coalition does a Team Bike Challenge as part of Bike to Work Day/Month. They change the rules each year, but basically your team earns points the more you use a bicycle for transportation.

A couple years ago, I "captained" a bike to work month team and got a few of my co-workers onto the team.  This requires identifying people who are likely cyclists who could possibly be convinced to bike commute regularly.  My team also had another person who already biked to work regularly during good weather. A couple of those team members are now regularly commuting to work on their bicycles, and one of them helps out at the local bike co-op type place now, too.

I think the two key aspects of this are:

Making it competitive provides motivation to do it day after day
Doing it day after day makes it a habit. Once you're in the habit, it's really no harder than riding to work.

A very close personal relationship

(borrowing a bit from moz's sexier answer on the original version of this question)

It can take several years. It's a very slow conversion process. Seems to have worked with freiheit♦'s current girlfriend, and with 2 of moz's girlfriends.

I think the fact that it's an activity you can do on your own, with your life partner, or with random acquaintances helps a lot.

Find a potential mate/girlfriend/boyfriend/spouse who is a potential cyclist
Through years of relationship, set a good cycling example
Help them get a bicycle (buy for them, help them shop, whatever) when they indicate interest (don't push)
Help them with any issues that come up. Fix a flat now and then, work on the bike (or get it to a shop) when maintenance is needed. Help them get the right accessories, etc.
Help them get that second bicycle when they figure out that the first one wasn't quite right
Help them get that third bicycle when they think they've finally got everything figured out just right.
etc.

Start early

Put your children on a bike as early as possible, first on a child seat on your bike (as soon as their head stands, 8/9 months) then on their own bike (3/4 years). Go to school by bike with them. Sooner or later, their mother will be converted as well.


Are there fenders designed specifically for bikes with racks?

Fenders don't fall into an "ok with racks" or "not ok with racks" category. Generally speaking, most traditional fender designs will work on bikes with racks attached. There may be certain combinations of fenders and racks that are problematic, but those are the exception.

An example of a problem would be a bike whose rear rack is very close to the top of the rear wheel - it would be hard to fit a fender in there, but that's a specific problem which requires a specific solution.

That said, when putting a lot of accessories on a bike, we should expect to be bending and cutting and filing as we go. We should not expect a front/rear set of fenders and racks to be a perfect fit on a frame out of the box unless each of those parts were specifically designed to be a fit with each other.


Bike type suggestion for packed limestone trails

No need to a full suspesion - waste of good money on these trails, you need $2K to get one thats half decent - however if you have got $2.5K burning a hole in you pocket, full sus will be more comfortable.  A Hardtail MTB is built a little heavier than a hybrid, but in the end, I doubt very much it would make a difference.

What I would do is look at some cheap upgrades to your existing bike. Go to the biggest tires you can fit (Without going insane) 2" would be good - rim width and frame cleance need to be considered. No only comfort, you might want to consider a shock seat post. These are a often considered "poor mans softtail", but do not get the attention they deserve - they do take some of teh stress and shock loading off the frame and wheels. They are great for taking the small ( <25mm ) bumps on these kinds of trail while remaining seated.

If you decide to go for a new bike, a quailty steel hardtail MTB or hybrid would be my pick (unless you can afford carbon or titanium), with low travel shocks (80mm, no more than 100). A 29er (29" / 700C wheels) rolls better over the rough than 26" and are ideal for these kinds of trails


I have to say I think this is a myth, for a properly built wheel.

Spokes have threaded ends which the nipples screw onto. Like almost all screw threads, they are self-locking. Since the spokes of a properly built wheel are under a high level of tension, there is no "play" in the threads. In addition, any torque would have to overcome the high clamping force the nipple head is exerting on the wheel rim.

For the spokes to loosen, the load would have to deform the rim enough to relieve the spoke of all tension so that the nipple can turn. If the spokes are this loose they would readily flex sideways if you pressed on them.

There is some potential for spokes to loosen a little with a newly built wheel, if the builder has not relieved the spoke torsion. In this situation the torsion in the spoke shaft can overcome the clamping force, and wheel will go out of true in the first few km of use.

See

Wikipedia: Screw_(simple_machine)
Vibration Loosening of Bolts and Threaded Fasteners
Sheldon on Wheelbuilding


What do the numbers of shimano components mean?

These are just editions of specific product lines. It's the same as BMW with the 3-series, 5-series and 7-series. Let's take Shimano Dura-Ace, for instance. It's traditionally a 7000-series of product numbers.

7200 - 1978-era Dura-Ace

7400 - Mid-to-late 1980's

7700 - 9-speed Dura-Ace ~ late 1990's

7800 - 10-speed Dura-Ace ~ 2000's

7900 - Current 10-speed Dura-Ace

And from wikipedia, For 2011, road bicycle groupsets include:

Dura-Ace Di2 [7970] (10 speed electronic)
Dura-Ace [7900] (10 speed)
Dura-Ace Track [7700] (NJS-approved, which is a requirement of all bicycle components used in professional Keirin racing in Japan)
Ultegra Di2 [6770] (10 speed electronic)
Ultegra [6700] (10 speed)
105 [5700] (10 speed)
Tiagra [4600] (10 speed) 9 speed on older models
Sora [3400] (9 speed)
2300 [2300] (8 speed)


The questions about the price is out of topic here because they are impossible to answer "universally", for the answer to be useful to more than one person, especially when no details about the existing setup are given. So let me instead outline a structure of the costs.
A new 1×11 groupset (cassette, chain, derailleur, shifter, front chainring, possibly front crankset, possibly new rear wheel) costs anywhere from 200 $/€/£ to 2000 and more, depending on what level of performance you want. An existing rear wheel may be sometimes preserved (again, we do not know your setup), but if you go for 1×12, you'll definitely need a new rear hub (essentially, a new wheel).
Smaller stuff, such as new shifting cables/housing, are worth as well, costing you maybe additional 10—30 $/€/£.
If you buy components online, add another 10—100 $/€/£ for postal services. If you buy at a bike shop, add implicit higher margin they have compared to online shops.
Then, there are installation costs. They can vary wildly: from zero if you are ready to learn the skills yourself, can loan specialty tools and have a lot of time to learn required skills, or have a friend that is willing to help you for free, to what price is for 1 or 2 hours of work of professional bicycle mechanic in your area.
Note that for these money, it is often possible to buy a complete new bicycle with entry to medium level of a 1×11 drivetrain. Selling your existing bike would even offset the cost a bit (I doubt that by much).
There are also cheaper wide range 1×10 groupsets (and even 1×9 and 1×8 by Microshift), which maybe are a better choice for upgrading an older bicycle.


What should I look for in a "trailer bike"/"tag-along" bike for a child?

Most of of trailer-bikes are pretty similar:

One speed. An inexperienced child will struggle to keep up when you pick up speed. She will also not be able to help much on the steep climbs.
No brakes. Your hands do a lot of work, and your stopping distance is longer.
BMX-style handlebar that can rock back and forth, as child size/shape changes
Attaches to tractor-bike's seat post. When you turn left, the trailer will lean right.
Flexy. As your kid gets heavier, this can make slowly climbing a steep hill really hard. You can't go straight.

I found that it was really good for teaching my son how to pedal, and build the appropriate muscles, so he was at an advantage on his own bike.

The flex was not an issue when we started, but a couple years later I had to retire the trailer. I couldn't track a straight line up a hill.

Some models have 5 speeds. That's more complexity, but if it breaks you can still get home. It can help a kid learn about shifting.

The Burley Piccolo attaches to a special rack, making it lean properly in turns and supposedly reducing flex.

I used to hitch on a standard 2-wheel trailer to my tandem-trailer, either to carry groceries or to pull my baby twins. We had 5 wheels, 4 people, were 16' long, and weight 400+ lbs. I had to take corners carefully.


Loud "thunk" sound each time my shoes pass the 1 o'clock position with both shoes

My bet is that this is caused by the bike rocking side-side as you shift body mass and pedalling forces. The noise is caused by the trainer shifting or perhaps the bike frame shifting on the trainer. The vibration or noise is coming through the frame and feels like it is emanating from the bottom bracket area.

Its sounds like you have ruled out the noise coming from the bottom bracket / crank area. I would spin the crank by hand with the bike in the trainer to make sure of this. Also grab the crank arms and push/pull in all directions to check for any play or movement in the bottom bracket.

If you have a smart trainer check that its axle does not have any play.

Try sitting on the bike and shifting it side-side, as if you were sprinting, but without rotating the pedals. Can you replicate the noise this way?

Can you ride the bike off the trainer to see if the noise occurs then also, or goes away?

Can you recruit a friend to listen and try to locate the source of the sound while you ride the bike? (Being careful to not get kicked in the head or tangled in the drivetrain of course.)


Why do shock pumps use a Schrader valve?

Schrader valves are stronger, for one. Breaking a weaker, smaller valve that has a (perhaps just in my experience) frustrating attachment mechanism for pumps on a $1,000+ fork would be unacceptable.

Road Bicycles

Schrader valves have at least one valid disadvantage on a road bicycle: their larger diameter is a deterrent for use because it reduces the strength of the rim significantly on a narrow-rimmed bicycle wheel (the main point), they use a spring that can wear out to hold their own pressure where Presta valves hold their own (ancillary point, if one at all) and are slightly heavier (retroactive justification from the Presta preachers). None of these matter for a shock.

High-end road bikes were designed for one thing: going fast. Their rim material takes an enormous amount of additional stress from the smaller width, higher inflation rates of the tires, and simultaneously have as much weight, material, and spokes taken away as possible to leave a somewhat durable wheel. In this setup, the hole diameter DOES make a sizable chunk out of the material and strength of the rim, and the smaller diameter allows for more performance and smaller width, lighter weight rims, and so is 'the thing' in the higher end models. Only a 6mm diameter hole is drilled vs an 8mm hole for a schrader.

Non-road Bicycles

Don't confuse 'costs more' with 'better'. In the mountain bicycle / BMX / downhill / trials / non-road bike world, the high end bikes are not all presta. Most utility bicycles (even expensive ones) are schrader for the convenience. They're more of an irrelevant (performance-wise) selection of what the rider wants on these types of bicycles. This isn't because they're skimping in other areas, but the Schrader vs Presta debate doesn't really matter when the rim is wide enough to compensate for the larger hole that must be drilled.

Other Applications

Also note that Schrader valves are much, much, much more common. They're used in refrigerant systems (both on your fridge in your home and in your vehicle's A/C system), plumbing test ports, pneumatic systems, hydraulic systems, and in many other industrial applications as well. I have never seen a presta valve that is not on a bicycle (so if industry is using them, they're cleverly hiding them everywhere I look). This makes the cost of design, tooling, and testing  a much less costly proposition for the manufacturer (and, in the end, the consumer) - by not having to break the trail for using a less common valve in an application it's not been used before.

A fringe benefit of Schraders that may or may not apply in this context is the removable core. When I was a Diesel mechanic the trucks would get ice and dirt lodged in the valve stems, and a simple tool would extract the core, leaving a decent size diameter to expel air, or shove a small screwdriver into to clear debris. Further, if the spring was ever worn, or the seal mechanism not sealing, this core could be replaced without replacing the entire valve stem, and it made depressurizing tires much more tolerable (take the cores out, walk away for five minutes). I couldn't imagine how irritating Presta valves would be. If the seal seat of a presta valve 'wore out', got chipped or otherwise failed on a shock, the whole valve would have to be replaced - which depending on the design, might be a permanent fixture in the shock tubing.


For downhill and all forms of trail riding (freeride, enduro, all mountain etc) the prefered way is 1 finger (index) on each lever. Anything else can be dangerous. If the brakes are not powerful enough for dealing with this then they either need fix or replacement to proper brakes for this type of riding.

Also, riders position the levers closer to the stem (leaving 1 to 2 inches space between the grip and lever clamp) in order to enforce that only 1 finger can go on the lever. This also helps the finger pull the lever from its most powerful spot.


Peugeot PX-10 with Shimano 105 Triple with BB-6700

Velo-Orange makes threadless BB's and French threaded BB's under their Grand Cru line. There is always also Phil Wood if you're rolling in money. They are all JIS (square) tapered. Some other companies (like Stronglight) have also made threadless bb's (for frames which typically have had their threads ruined) in the past - I don't know if this is current.

I'm not entirely sure what BB-6700 has to do with this, though.

I think I see why BB-6700 may be there - you're trying to get a hollowtech/octalink/some other type of setup going. As far as I know, nobody makes a product which will allow you to do this.

You'd either:

have to force some other BB on there and ruin the threads for the BB
take the frame to a frame builder and see if they can do some magic to get one of these things in.

Shimano does still make new cranksets which are JIS tapered in the Sora line, but if you want something fancier, you'll have to go with an older used crankset. You can always get nice new replacement chainrings if they're a bit worn.

Edit: Just saw the outboard bottom bracket page from Phil Wood. Its expensive, but I think it may work depending on the crankset you want to use.


I can't speak as a user of them, but I can as one who has followed them. They seem to work reasonably well, but they aren't as good at protecting people behind you - the arc behind them is narrower than the traditional curved in guard. I would think that in this regard, wider would seem to be better

In this they are better than the horizontally flat guards you see, which do nothing to protect those following you.

If you're only worried about your back and legs, these seem fine - but if you're concerned for your fellow travelers, I'd be less keen on them.


How long should it take to rebuild a wheel?

I think if you are willing to spend a few hours, it's worth doing yourself.  Depending on the flange size of the new hub, though, you may need to buy new spokes.  You can determine the length of the spokes you will need using a spoke length calculator.

You will need a spoke wrench, a flat-head screwdriver, some vaseline, and the use of a truing stand.  Here's what you'll have to do:

Remove the tire, innertube, and rim tape from the wheel.
Using a spoke wrench, loosen and remove the nipples.
If you are using the same spokes, remove the spokes from the old hub.
Lace the wheel, making ABSOLUTELY CERTAIN that the valve will be in the right place.  Check out Sheldon Brown's step-by-step wheelbuilding page for the procedure of lacing a 3x (three-cross) wheel.  You will want to use a little bit of vaseline on the threads of each spoke so you can tighten the nipples more easily.
Go to a nearby bicycle cooperative (you can google bicycle co-op near nameofyourtown) to use a truing stand, and use the truing stand to adjust the wheel.  Make sure the wheel is dished properly and that you have proper tension on the spokes.

Because spokes stretch a little and settle in after you start riding, be prepared to true the wheel after the first couple rides.

If you are not interested in making your own wheel, I recommend just buying a new wheel with the hub you want.  It may be cheaper than getting your lbs to rebuild your wheel with your new hub.


Nexus IGH reluctant to shift after applying load

Yup - I've had this exact experience on an Alfine 11.  If you pedal in smooth circles and maintain the pedal pressure, its possible to shift a long way through the gears before the gearbox catches up.
At that point the gearbox will quickly move across up to 5~7 gears in one quick movement, which can be a massive drop in pedal cadence and is able to upset the rider's balance.  I had a couple of close calls because of this.
Upshot, an IGH is opposite to a conventional deraileur, in that an IGH needs a brief pause in the power to shift UP (to a harder gear) whereas your common bike transmission needs the rider to let off the pedals briefly while changing DOWN to an easier gear/larger rear cog.
You can also try accelerating with a distinctly choppy pedal stroke, which may help the fast acceleration or sprint start.
I never figured out whether this "delayed shift" was bad for the gearbox or not.  Mine lasted around 15,000 km before shifting went unreliable, and while there were always tiny flakes of brass in the oil, it never became more or less, over time.

SEPARATELY  The other thing I've noticed with IGH, both my alfine and a couple of 3 speed nexus bikes at work, is that the yellow lines aren't perfect.  You might find the bike's shifting improves if you put a half-turn on the adjuster away from "perfectly-aligned" but it could be in either direction.  Try twiddling the adjuster on your next ride, and see if it gets better being not quite perfect.
Lastly, also remember these hubs need service - an oil change yearly or every 5000 km is the shimano recommendation.

As for water in your cable, yes its definitely worth fixing that.  The water will cause rust and/or will collect dust/dirt and add friction  This will make the cable's movement sludgier, to the point the hub's spring can no longer overcome the resistance.
You could unscrew the barrel-thingy on the hub end, pull the inner out of the outer, blast some compressed air through the outer and follow it up with solvent, then a day later drop some oil in and let it dribble in.  Clean the inner cable too.
This depends on whether the inner cable can be reinstalled.  The inner cable should slide through the outer with minimal force, if you have to tug it then its gunked.
Last option there is a replacement of the inner cable and outer housing.  Not hard but fiddly to get the length exactly right.
Keep your bike inside, or at least under cover over night at a minimum, to prolong its life.


Bottom jockey wheel on rear derailleur keeps skipping chain

From the the photo of the derailleur it's obvious that the derailleur cage is not parallel to the sprockets and wheel. The bottom run of the chain returning to the crank is leaving the cage at angle.

The derailleur hanger that attaches the derailleur to the frame is bent and causing the misalignment, and I think the cage may be deformed as well.

There are special tools for realigning the derailleur that a bike shop can use, but it's possible to improve it by hand. From the back of the bike look down the chain. The cage should look parallel to the chainrings. You can grab the derailleur and bend it back into alignment.


Might be that both tubes have punctures, perhaps because they are old and have cracked.

Might be you are not getting the pump on the valve properly. Most kids bikes use the wider Schaefer type bales, made sure you are using the correct pump head.

You can try taking the bike to a local bike shop, the usually have a good floor pump with s pressure gauge for free use.


Remove front derailleur without breaking chain

The pictures I've found of the FD-TY18 look like the pin across the rear of the cage is riveted in place. So, you probably can't remove it without a bit of work – through if the derailleur is damaged beyond repair it probably won't be too hard to either pry it apart (try holding with a screwdriver and twisting one side with pliers) or to cut it (and do double check that there isn't a screw there).

But before you do all of that, check your chain carefully. Many chains these days are connected with a master link which makes it easy to split the chain without special tools.


What are the advantages of having more than one bike?

Rule 12 says that you should aim to own N+1 bikes, where N is the number you have now.  While that's completely tongue-in-cheek, there's some merit to having gear fit for purpose.

For example I have a fast road bike, which is uncomfortable in the rain and useless for carrying stuff.  I also have a 20" folder with carriers and mudguards/fenders, which is okay for moving things, towing a trailer, and works well in the rain.  But fast it is not.

The advantages of multiple bikes is flexibility

Each can be set up for specific types of riding
You can have a dedicated rain bike without having to add stuff
Spare bike to ride if one is down for some reason
Spare bike to offer to other people if they visit

The disadvantages are

Extra cost - bikes aren't as expensive as cars, but aren't generally free either.
Storage space - you can only ride one at a time, the rest will be stored somewhere.
Upkeep - more bikes means more things to maintain and service, but your mileage is spread over more things.
Records - you will need to keep better records over what was changed when, and how much mileage a bike has done.  I use strava for this.

In your case, the bike might be "over the recommended load" but you're working on that BY riding.

If you find that the bike is not performing to your needs then an additional/replacement bike might help.  This is different from you not performing as expected!

What would a fatbike do for you that your current bike doesn't?  It would likely go slower, weigh more, be harder to climb grades, and tubes/tyres are expensive.  On the plus side it would "float" over sand snow and loose dirt better, but it is not necessarily going to be any stronger or tougher than your existing bike.

You're only 20 kilos heavier than me, and you've already uprated the rear wheel.  I'd suggest riding it while you work on your fitness, and plan on a replacement bike in a couple years.


Huffy Cranbrook 26" Ladies' Cruiser crank / pedal / chain "pop" sound...?

My guess is that the chain is too tight. You say it is only at a specific spot in the rotation which leads me to believe your chainring being slightly off center (I have not found one 100% perfect) is causing the popping.

Flip the bike on it's back and spin the cranks slowly. If it is a freewheel pedal, it backwards since this will not engage the sprocket. If it is a coaster, you will have to pedal it forwards. If you notice the chain get really tight then loose as you do this, adjust your chain. Find the same spot the pedals are at where it gets the tightest and loosen then tighten the rear wheel with the cranks in the same spot so that the tightest it will get is where you just set it.

If the chain tension was not the problem, you might need to check the bearings. Huffys almost never have sealed bearings and they can be over under tightened, either being a problem.


Do I really need two bikes - one for road cycling and one for daily use?

I don't think that we would all agree on an answer to the question about whether it is ethical to have more than one bike; opinions vary.  Many of us here on this web site have more than one bicycle, so I would say that in many parts of the world, owning more than one bicycle is common.  Many of us joke that the correct number of bikes to own is n + 1, where n is the number currently owned, but we are kidding.  Whether you need a second bike is a question that only you can answer.

Some people only wish to own one bicycle, so they disguise a nice bicycle with a bad paint job to look like a low-quality bicycle.


Cheap 14-34 Shimano 6spd freewheels are still being made.

As for freehub body swapping, there are a couple things at play. One is the compatibility issues with swapping freehubs at all, and the second is issues related to hub spacing, axle spacing, and wheel dishing with making the swap in question if it is possible.

Across manufacturers, there is no real freehub swap compatibility (barring cases where two different OEMs use the same Joytech hub etc). Within manufacturers there can be some. Many Shimano hubs use the same spline pattern and dimensions at the interface between shell and freehub body, and can have freehubs interchanged. Many of the common 8/9/10 Shimano freehub bodies are very close to dimensionally the same. (One sticky point here is that they can look dimensionally identical but usually need their cone/dust seal/spacers etc to be that of the hub they came from. You should assume that's the case unless you want to play games making it work right.)

That said, there are a couple exceptions to this within Shimano (completely different shell/freehub body interfaces), and 7 speed hubs are where at least one I know of can be found. So even if both freehubs in question are Shimano, it depends on the specific hubs models.

Secondly, if both are interchangeable Shimano freehub bodies, 7-speed freehub bodies are shorter, so to get the spacing back to where you started on the MTB wheel you'll have to add spacers on the left side and then re-dish the wheel. (I recommend doing it this way, because then you get more total spoke tension. You don't get all the strength benefits of a 7-speed hub because it will still have the flange spacing of an 8-speed hub.) And then on the folder hub, you'll need a longer axle.

Also I should note that just respacing the folder's existing rear wheel to 7-speed, swapping axles if needed, and then redishing it is another possible course here.


1 inch threadless headset with hollow cap for cable routing

You're looking for a Potts Mod, which allows you to route the front brake cable down through the fork's steerer and out to the front brake caliper.

This will allow the front fork/wheel/bars to do a complete rotation without binding on cables.

A Potts Mod does not work for a back brake - for that you require a "detangler" or to fit coaster brakes, aka back-pedal brakes.


do DT Swiss 240 hubs need proprietary tools to maintain them?

For the bearings you do need the tools. The hub is advertised as a tool-free maintenance hub, but that's only for light work. Check this post out on bikeradar.com:

  I recently e-mailed DT-Swiss on this
  topic and here's the conversation -

  Me - "This one has been mentioned by a
  couple of people - you advertise a "No
  tool concept" and a "No tool
  maintenance concept" while in actual
  fact only the drive mechanism is
  serviceable without tools and the rest
  of the hub requires expensive special
  tools. I've tried to explain before
  that bearing replacement probably
  falls outside of "maintenance" and
  enters the "overhaul" category but the
  quote "No tool concept" has being
  thought misleading. What answer do you
  have?"

  Them - "I've fielded many questions
  about the no tools concept too. It
  simply means that you do not need any
  special tools to perform normal
  maintenance such as ratchet cleaning
  and re-greasing. This should be done 1
  to 3 times (on average) a year,
  depending on your riding conditions.
  This is a 5 min procedure, even for
  the inexperienced. When you open up
  our tech manuals, the first picture
  you see is of a tool set, which looks
  scary and complicated. I can see how
  this seems misleading. The tools are
  required for more in-depth work such
  as bearing replacements. Want
  cartridge bearings? Then you need
  tools to install them. If tools were
  not part of the equation, then your
  bearing would simply fall out and the
  hub would be chronically loose. Show
  me a hub of any quality that does not
  require tools for complete
  tear-downs."

The tools are pretty expensive though.
http://www.amazon.com/DT-Swiss-DT-240-440-FR-front/dp/B001CK0S22

You might want to drop at the local bike shop.


Babies on Bakfietsen: How young is too young?

that's me in the picture above! Hi, all.

I carried both my babies by bike-- they came home in-arms onboard pedicabs, and started in the Yuba rig pictured quite young (baby #1 at 7 weeks, baby #2 at 3.5 weeks).

The American Pediatric Association says babies should not ride on bikes until they are one year old and can support the weight of their head + a helmet while sitting upright in a child seat or trailer. They vaguely cite vibration damage to the spinal cord as reason to refrain from carrying them younger, though if anyone can show me the study that indicates that a baby in a car-seat onboard a bike suffers more jostling than a baby in a stroller or a baby-carrier, I'll give you $50.  I've searched, including PubMed and other scholarly databases, and it appears that the APA's finding is based entirely on speculation rather than scientific analysis. Which makes sense, as Dutch infants travel this way all the time without a rash of bike-based brain injuries. I am unconvinced by the APA's recommendation and, for my own children, have chosen to ignore it.

Any form of travel is going to involve some bouncing; once you decide that your baby will benefit more from leaving the house than from being safe inside it you are exposing him to some danger. Auto accidents are the leading cause of death for children in the US, remember. So get over this notion that bike travel is this exceptional form of risk for your baby.  We put some foam under the strapped-down car seat to add a bit of extra suspension, and were as careful as possible to choose the smoothest available line while riding, but ultimately, some bouncing is going to happen. And that's probably fine (add caveat here where I am not a doctor nor a lawyer, just a mom with two healthy-and-clever-so-far bike-carried kids, ymmv).

So my feeling is, as long as your kiddo is reclined and secured, even the littlest babies are safe on bikes, as long as the bikes have competent riders and safe places to ride.

Nota bene: a baby in a car seat should not wear a helmet: the extra material under the back of their head would put unsafe strain on their neck and defeat the purpose of the reclined & secured position. This means that, in states with a child (or universal) helmet law, carrying a baby on a bike is de facto illegal. I feel that strapping a baby to a big seat-shaped piece of styrofoam rather than a little head-shaped piece of styrofoam provides similar protection, however, the letter of the law in my state (and maybe yours) disagrees. I'm grateful to have never had to take the issue to court, and haven't heard of anyone else doing so either. But, something to keep in mind.

For another perspective on this issue, see: http://totcycle.com/blog/baby-on-a-bicycle.html

Also, the SF Bike Coalition's Family Biking Guide has a great section on biking with infants: http://www.sfbike.org/?family_guide


Yes, all Shimano 11-speed road cable pull is the same.
The long armed 11-speed FDs like FD-5800, 6800 etc can all be and frequently are replaced with the toggle models, i.e. FD-R8000.


Do single speed/fixed bicycles come with machined rims?

It depends on the fixie.

A lot of them don't because brakes are not cool among the fixie riding population (since they primarily want deep V rims to look nice and resistance braking).

As for not having machined rims, depending on what the rim is coated with it can be OK -- if its powdercoated/painted for example, it will be too slippery to brake, but annodized surfaces can be used for braking just fine. The rims on the Masi should be annodized so you should be good for braking.


Will speed/cadence sensor work with 650c bicycle

With common digital cycle computers, wheel size shouldn't be an issue as you can configure them to work for any reasonable tire size on the market.


Clutch rear derailleur vs chain tensioner / guide

"Once or twice per ride" - that is way beyond what I would consider only. That would destroy my confidence in the bike and ruin any enjoyment I got from riding.

A new dérailleur might help, but might not. There are other things I would look into first, PeteH in his comment is correct - the number of drops you are suffering is an indication something is very 'not right'. If a new Clutch dérailleur appears to fix it, its is probably just masking the problem. Chain guides hide all sorts of evils, but are a practical option that will work.

Shimano 1x10 was not an out of the box set up, what was the original setup and what has been replaced with what?

What chain ring are you running, is it damaged at all?. If you are running a normal 3x or 2x chain ring, a chain-ring for a single will help, especially a narrow/wide.

What is the chain line like. When you drop the chain, is it in normally in a particular range of gears

Along the same lines - is the chain length correct. As its a long cage dérailleur you have a lot of scope for too much chain.

How worn is the dérailleur - its more likely a new one will help of its been used a lot.

With so many unanswered questions,  I would consider a new dérailleur if the other is well used, but would focus on chain (how old, does it need replacing and length) chain line and chain ring first. If these are all good (and the chain ring is dedicated for single, ideally narrow/wide), the choice is a new dérailleur which might work, a a chain guide while will work.


I also considered doing this.

Firstly what type of brakes you have will depend on what you need.

You need to look for

size. Most important get the same as you have already. Also check the rim width with rim brakes as mentioned in comments below
weight -if you have money to spend get some quality lightweight ones. If they are better than your existing ones, consider these you new summer ones and use the old ones for winter
brakes (disc or rim) If you have disc brakes you will need rotors too, or you'll be swapping them out all the time too.
cassette. You'll need a wheelset which can accommodate a cassette that matches the the current one on your bike. There's no need to replace the chain if you are getting the same speed (number of cogs) cassette. Genreal consensus in the comments below is also to replace/swap the chain.

Also cleaning the chainset will help a great deal in looking after your bike for the winter

So in summary you will need a new cassette and new disc rotors if you have disc brakes to save you swapping these out all the time.

How often do you change the tyres? is it worth the cost if you change them 4 times a year?


The events and symptoms you describe don't give a clear picture of what happened.

At the end of a ride a week ago something happened inside it and it stopped shifting altogether all of a sudden. The feeling was as if something disconnected/snapped.

This is consistent with a cable snapping at the head. Some past versions of Shimano STI shifters may have had a tendency to do this. Your gear and shift cables have a little round head that stops them in the lever, and the cable may have broken just below that. Presumably, your bike shop changed that cable.

The shop should have adjusted the derailer, or rather adjusted the cable tension so that the derailer shifted properly. Based on this sentence, the shop either did not do this, or something else happened to your bike in the interim:

However, the shifting is not the same anymore. It is impossible to adjust the shifting so that both of the following work: big chainring + smallest sprocket and small chainring + biggest sprocket.

Did you or the bike store adjust the limit screws? These adjust how far each derailer can travel. If you have them set too far in, the derailer may not travel far enough to shift into the specified cogs, which would reproduce these symptoms. However, you imply that you can shift into small/small and big/big, making this less likely. (NB: if the shop just replaced the cable and brought it to the right tension, they should not have touched the limit screws unless they were wrongly set to begin with.)

The shifting is also clunky no matter what. The chain will always rub against the next sprocket before shiting to a bigger one and will often slam into smaller one. Regardless of how much I fiddle with the barrel adjuster. Also, shifting from 6 to 7 or 7 to 8 smallest sprocket requires two clicks of the lever and a downshift afterwards.

These sentences are consistent with the cable tension being wrong, despite your adjusting it. If you're unable to follow the instructions for adjusting your rear derailer, have the shop do it. NB: it's not a mark of shame if you can't. Many people will pleasantly surprise themselves, but not everyone has mechanical skills, and there's no shame in not having them.
Another possible cause of poor shifting is if you dropped your bike on the side with the derailer. Novice cyclists commonly do this, as I can attest from experience. You may be surprised, but the derailer hangar (the removable piece of aluminum where your RD bolts in) can bend very easily. This is by design: in a major crash, it is meant to break before the frame takes damage; if it were a structural part of an aluminum or carbon frame, then many minor crashes or coffee shop bike spills would ruin the entire frame.
From your photos, it doesn't look like the hangar is bent. However, you have the camera angled slightly.

Last:

... both times, the shiter looks and feels differently than before the incident. The lever is angled a bit more towards the frame. The braking aspect of the lever is now different as well: the distance from the lever's resting point to the "max brake applied" point is around 6 mm shorter.

You said the right lever now rests closer to the bar. It sounds like someone used the reach adjustment. You can control how far the levers are away from the curve (i.e. the drop) of the bar with a little allen key under the hood. It's of immense benefit to smaller riders. This wouldn't affect the shifting by itself.
A side note for those interested: you seem to be saying that the lever travels a shorter distance before the brake pad hits the rim. On hydraulic brake levers, this phenomenon is known as setting the bite point. On those levers, you can adjust that independent of the lever reach. This is not applicable to rim brake levers, however.
Initially, I thought that your right shifter was twisted inwards on the handlebar, but I noticed that the photo is not consistent with this.

English being your first language is unlikely to be the issue. The problem is more that you're new to bikes, you don't know exactly what symptoms you are having how to describe them in technical terms, and none of us are physically present with the bike. You can try to follow the video by Park Tools. You should be able to check by eyeball if your derailer hanger is straight. If this doesn't resolve the problem, you will need to take it in to the store. Again, there is no shame in having to do this. It takes many cyclists a fair bit of fiddling to understand how our derailers adjust. Until I understood that process, I was essentially turning screws and cable adjusters without any clear purpose.


10 speed rear derailleur to shift 11-40 cassette on 3x10

For this setup you would need a derailleur with a capacity of (52-30)+(40-11) = 51 teeth.  This page states that the SGS has a total capacity of 45 teeth. That's seems quite a bit below what you are trying to do, even if you don't plan on running big/big.


My road bike seems slightly too big for me

Because I feel that I'm stretching a little too forward, causing my back to ache, I've decided I would decrease my stem from 110 to 90.

You can help this by also moving your saddle forward.  If you combine that with raising your handlebars some by changing the stem angle, you'll shift your torso to be more upright, too.  That will also shift your weight back a bit, putting a bit less pressure on your hands and a bit more on your bottom.

Moving the saddle forward would also slightly shorten the reach to the pedals.

  165 cranks are rare

They sure don't seem to be.  A simple Google search returns many examples of Shimano 165 mm cranksets that would likely all be compatible with your bicycle.

  Also my friend is saying that changing my Ultegra BB to a Dura Ace BB would make my ride much smoother.

Hogwash.  You wouldn't be able to tell.  You'd probably be surprised at how many amateur road racers use things like Sora or Tiagra cranksets, or won't bother paying more for Ultegra - much less DuraAce - over 105 or today's Tiagra.  (Wheels are what gets the money - good aero wheels can save 40 or 50 watts - maybe more - at 30+ mph...)  Pros and higher-level amateurs ride high-end bikes because they get them for free - it's marketing aimed at getting you to pay a premium for bling.  DuraAce doesn't make your bike faster.  All it really does is make your bike a little bit lighter and a lot more expensive.  How much better is a $275 DuraAce crankset than a $65 Sora crankset anyway?  IMO, don't worry about the grams until you get down to 2% body fat.


If the click is felt in both pedals the problem is likely to be the bottom bracket bearings.

You should be able to feel bearing stiffness, roughness or 'notchiness' be turning the crank manually. It helps if you can get the chain off the rings to do this so the crank turns freely. Also check for any play of the crank axle in the bearings.

If the crank axle is not turning smoothly in the bearings or there is excessive play you likely need a new cartridge bottom bracket unit. These are not expensive but require special tools to take off the cranks and extract/install a new BB unit.

It's a bit worrying that you are finding loose bolts all over your drive train. You should probably do a complete drive train checkup to make sure there are no other lurking problems.

The cranks bolts are of special concern. If the alloy crank arms come loose on the steel axle taper they can be terminally damaged in short order. The bolts can be removed (the crank will stay on the axle), the bolt and internal thread in the axle should be cleaned and de-greased then the bolts -re-installed with non-permanent thread locker (e.g., blue Loctite) and torqued to proper specification. (This will of course all get done if you replace your bottom bracket cartridge.)


Why is my abdomen much cooler than the rest of my body after a ride?

This part of the body isn't doing much, unlike other areas, so isn't warmed by blood flow and muscle activity. It is exposed to the wind, and can get a little sweaty quite easily, even if the ambient temperature isn't all that high, but it's also sheltered from the sun. The climbs probably got you sweating, then the descents would have significant wind chill.

Even if you don't have fat to insulate your digestive system, there's still a layer of muscle between it and the skin, so the skin temperature there isn't the core temperature (if it was, there wouldn't be so much need for internal medical thermometers).

Don't listen to whoever told you warm water doesn't get absorbed. It's hard to prove a negative, but if you've ever ridden all day in the warm with only warm water available and no need to go to the toilet despite drinking loads it will be obvious that it's getting absorbed (even if it does turn straight into sweat).


Preparing for long term storage (2 years)

Your plan sounds pretty sane to me.

Depending on how tolerant your parents are, I would prefer to leave the bike intact and open to the air, so it can dry if it gets damp, but that may not be possible.

I returned from uni, a long time ago now, and dug out my old mountain bike. It hadn't been prepared for 3 years on its own but came out just fine, less a few parts my brother had relieved me of.

When you return you'll want to give them a pretty through service but over 2 years nothing much should have degraded.

Tires would most likely be fine, if they're tubeless the sealant will have dried out and either disappeared or formed a lump of goo. They'll be flat and may crack along the fold.

Some bolts will have some surface rust.


What are the different uses for the 110 vs 114 vs 116 link bike chains?

This is one of those topics where the answer has changed with the new directions that bike drivetrains have gone in recent years.

With any chain packaged for consumer use, the basic idea is they come long enough to cover all the common use cases, and you should expect to cut it down to fit your bike. On a derailleur bike, the right length is usually seen as being a function of chainstay length, the size of the largest chainring and cog, and whatever extra length the rear derailleur maker recommends. On suspension bikes, the effect that suspension travel has on effective chainstay length must be accounted for.

Optimal chain length itself is a topic there are many questions here about, and there are more ways of doing it that might lead to different results than might be initially suspected. For example, for road bikes where you want to have wheel/cassette swappability to take full advantage of the rear derailleur's maximum capacity without having to swap chains along with wheels (for example to swap in an 11-28 cassette for a climbier day versus 11-23 for flat), in the eyes of many it makes more sense to size off the small/small combo, even though no manufacturer recommends this approach in their instructions.

However, what's happened lately is there are more bikes with drivetrain setups that feature both "big" chainrings and cogs, sometimes alongside tires with bigger  outside diameters than in years past, and the longer chainstays that come with them. For example, an extreme example is in the shop I work at, we handle a certain "adventure touring"-ish bike that comes with a 48t large ring, 34t large cog, and 700x48 aka 29x1.95 tires with chainstays even longer than strictly necessary for that tire size. It needs a 118 link chain, which exists but is uncommon, and it's a frequent mistake for people and even mechanics to go to install a replacement chain onto it and find the one they picked out comes too short.

From this you can probably infer how different bike categories creep into needing the less common 116 and 118 link chains even though historically 112 and 114 have been enough. Honestly this is an area where a lot of mistakes are still being made and what appears on retail shelves hasn't necessarily caught up to the greater diversity of bikes out there. I don't think it's so much a matter of manufacturers or retailers pinching pennies on the extra links; probably before long there will be a new equilibrium and most chains will come at 116 or perhaps 118.


Can I install a front derailleur for my bike?

I would say on this bike you can install any cheapest aluminum crankset, cheapest front derailleur and a friction (non indexed) shifter, where the crankset will be the most costly part (about 30$) and a few dollars for derailleur and shifter (each). So if you able to do the work byself you will end under 50$ for all that upgrade (but those should be done well), however if you want LBS to do the work it should cost about 20-30$ more (I don't really know the work costs in other than my regions).

EDIT:
As Batman mention in the comment, your BB can be too short for triple crank. If it is, the upgrade can't be done without replacing the BB too.
I didn't include tools cost in my answer.
And to get this work done you have to have appropriate knowledge.

As bikes have different width seat tube, your derailleur must fit it. If your frame tube is thin (and it looks that this frame has thin tube) you can take a little wider derailleur and put a holder plates between it and the frame. Of course you should check that the derailleur will be compatible to your crank teeth count.
It may seem difficult, but in LBS will be done easily. But you should compare it's cost, and cost of a new bike of same quality with front gears.


Twist shifter cannot shift down – what might be the cause?

Without the shifter's resistance, the rear derailleur pulls towards the smallest cog (highest gear). This would also happen, e.g., when the shift cable snaps. (Rarer 'inverse' derailleurs would pull towards the largest cog.) To test the rear derailleur, pull the shift cable with your hand while turning the crank; if the derailleur moves and pushes the chain towards the biggest cog, it means the derailleur is ok.

If the (indexed) shifter doesn't click anymore, or if the internal catch doesn't seem to withstand the pull of the derailleur, it's most probably time to overhaul or replace the shifter.

It may simply be that old grease in the shifter has hardened up over time, so that the catch mechanism is stuck. This should be mendable if you open a cap of the shifter casing until a hole is revealed (used for threading in the cable), and spray in a generous amount of a light lubricant that will solve and flush out the sticky grease. WD40 is known to work quickly in such a job, but others also work well and may have better lubricating properties than WD40.

If lubricating doesn't help, it's possible that some internal part is worn out or broken and needs to be replaced. If spare parts are not readily available, it's a case for complete replacement.


Why aren't winter bicycles camping events common as the motorcycles one?

I haven't been in an organization that would have considered arranging such event and then decided not to, so this is pure speculation. I have a guess with two reasons: weight and competing activities.

First, winter camping requires much more equipment than summer: heavy sleeping bags, warm clothing, fuel, and taken to extreme a tent with stove. These are not fun to carry on a bike, especially when dealing with snow at the same time. Powered motorcycle lets you put all the effort to maintaining balance and helps with cutting through snow.

Second, if you are camping and traveling under your own power in snow, skis or snow shoes combined with toboggan for carrying your stuff are a better choice. Instead difficult adapting to snow, they have evolved just for snow and allow you go literally off the beaten path. A bicycle would be just trouble.

Third, not directly related to winter, there aren't many cycling events like motorcycle rallies in summer either. Mass events for cycling (or skiing for that matter) tend to be more or less race-like. With motor vehicles these would be very illegal.


Normally the rotors will be separate. Also, there are two kinds of rotor mounts: 6-bolt and centerlock. You can get an adapter to put a 6-bolt rotor on a centerlock hub (I don't think you can go the other way), so it's something to be aware of.


Looking for 26 x 1.6 tires is there an alternative.

The 1.6" width is oddball, but you don't have to use 1.6" exactly. The common sizes in that area are 26x1.5 and 26x1.75. The frame will probably have clearance for both, although 1.75 is obviously a little larger so you'll have to check if you want to go wider.


The cost of replacing worn parts is one part of the issue with excessive chain stretch, safety is another component.

Safety

This type of problem will take a while to emerge, but if you are going to run the drivetrain into the ground, at some point your safety may be compromised. Excessively worn chains may break, or skip over excessively worn gears.  At some point you can wear the gears so much you can shear the teeth right off.

If this happens when riding out of the saddle (e.g., accelerating hard or climbing) you can actually be thrown off the bike and into traffic, crash and hit your head, crash your sensitive bits into the stem, or otherwise be embarrassed.  The list goes on.

Will this actually happen to you? Who knows, but you should know that it is a risk.

Total Cost of Ownership

If you let the chain wear excessively you will at some point have to replace:

Chain;
Cassette;
Chain Rings; and
Derailleur pulley wheels.

Chain rings alone can be the cost of 2-3 chains depending on the quality of rings you go for (more if you have a triple chainring).  Cassettes usually cost the price of about 2 chains. Let's put the price of derailleur pulleys at 1 chain (this is up for debate). And a chain costs the price of 1 chain.

That brings the total cost of a drive train to 7 chains.  You would therefore need to get about 6000-8400 miles out of your single chain before the economics start to be in your favour.  Do you think you can do it or will the chain break and become a mangled unusable mess?  When that happens you are stuck replacing everything. Even if you hit 6000-8400 mark, how far beyond it will you get?  Only after 8400 miles are you starting to save.

Also don't forget that a really worn drivetrains shift horribly so you will also need to factor that into the cost somehow.  Is a louse experience worth saving a few dollars?  Only you can answer that question.

The only place where this strategy might work is for single speeds as cogs and rings are relatively cheaper and shifting is a non-issue.


What is the men's version of Trek Lexa SLX

Looking around their site, the Madone 2.1 seems to have similar components, yet is only $1,319.99 compared to the Lexa which is $1,649.99.  Looking over the specs,  I can't see why there is such a discrepancy in the price.  The Domane 2.3 is also quite similar and has the IsoSpeed decoupler on the frame and appears to hace rack mounts based on the picture. It is priced at $1,869.99.

There also seems to be a substantial price difference between the Silque and the very similar Emonda S4, which are priced at $2,089.99 and $1,649.99 respectively.  It's interesting that the women's specific models seem to be so much more expensive.  Maybe there's something I'm missing out on with the pricing.


Dual position air, solo air, coil, rebound: what do they mean about forks?

There are two parts to a fork, the spring and the damper. Solo air, dual air and coil are all types of spring and absorb energy when the fork is compressed. The damper, which is the part of the suspension system that removes oscillation after the spring has absorbed energy and is returning, is generally a hydraulic system filled with oil. The Lyric has an oil damper as well as a coil or air spring.

A modern air spring generally has two chambers one positive and negative, the positive provides resistance against compression and the negative resistance against rebound as the spring returns to it's normal length.

Solo and Dual air are RockShox terms for their proprietary air spring system and relates to the way the shock is filled, but both are dual chamber. Until Solo air forks became available (2012 or 2013 forks) it was necessary to tune both chambers to get sag and rebound correct, now solo air is a single fill system that does this much more easily. Dual air (as opposed to dual position air) has now been replaced completely by solo air on the RockShox range.

  Dual Position Air

  Dual Position Air is another proprietary RockShox technology and is a
  type of air spring that allows for travel to changed between two travel lengths through a lever on the crown. It acts in the same way
  as a solo air spring but gives the rider greater choice on a ride.

A coil fork uses a mechanical spring in place of an air spring. A coil spring is simply that, a big metal spring.

The benefits of the two types are often debated. A dual chamber air spring fork is lighter than a coil spring but requires more tuning. A coil fork has a finite stroke length so the rebound is smoother at the end of the stroke and makes the fork feel more plush throughout the stroke.

It would be redundant to have both a air spring and coil spring in a fork, as both are springs and neither are dampers. The fork would bounce back and oscillate (bounce up and down like a spring until all energy was released). There have however been bikes with two stage suspension systems like the Elite9 which used dual rear shocks and could effectively line up a coil and air spring shock.


You likely won't find anything conclusive, because the required testing would be so varied.

Anything done poorly can cause problems.  Any sport lends itself to an increased chance for injury.  However, proper technique and equipment generally alleviates some, if not most of that risk.

In cycling, proper hygiene, attire, technique and bike fit are all important.  Keeping your skin clean (before and after rides).  During rides (especially longer rides) chamois cream of some sort can help immensely.  Bike shorts are made for a reason: they work.  They should also be clean, however.  Other attire is also important.  Overdressing and sweating yourself out only creates a breeding ground for bacteria.  Remember body odor varies from person to person, but is largely caused by the flora on the skin.  No reason to build it a Disneyland unnecessarily.

A properly fitting seat and bike will minimize friction and irritation.  These factors can cause surface skin damage which then leads to infection (saddle sores, etc) after the skin begins to break down.

If you are referring to bladder infections, I think it would be a long road with a lot of ignorance to get there.  While females are generally more prone to UTIs, and cycling could increase the risk of those, the steps necessary to reduce the risk are quite easy and really part of basic hygiene.  Getting a UTI and then ignoring it long enough for it to hit the bladder would require an additional step of disregard.


I've read that higher volume tires work better with lower pressure, but for what it's worth, you'd be better off trying it on the trail and seeing for yourself.


Will a Mishiki Pueblo Mountain 20 in frame hold my weight. I go about 330

First congratulations for getting back on a bike. As others have stated the typical weak point will be the axles and wheels. I would recommend having the wheel bearings serviced by your local bike shop. Ask them to check the spoke tension as well. I've seen quite a few low end wheels with poorly adjusted bearings and almost no grease in the hub. I would then run the tire pressure to the max spec on the tire sidewall. Even then they are likely only suitable for pavement or bike path use. If wheel problems occur consider investing in a set of wheels designed for a tandem bike. They are capable of supporting 2 adults. While they will cost more then your current bike you can use them on your next bike when you upgrade. Another option is a used LandRider auto shift. They are frequently listed on Craigs List for under $200 in my area. They are rated for 350 pounds


The pawls in your freehub are most likely getting stuck, causing them not to lock and transfer the force from the cassette to the wheel. In your case as the bike is new it is probably due to it being assembled with grease rather than a lighter oil, but the problem can also come with ageing. You will need to rebuild the freehub. This is not the easiest procedure and requires some specific tools (chain whip and freehub nut at least) so probably get your bike shop to do it.

The unusable gears on the back could be a number of things, rear derailleur limit screws, lack of cable tension, bent hanger/derailleur... If you are already taking it to a bike shop just ask them to fix it.

EDIT: Based on the additional information (-30 not 30  Celcius and secondhand), like others say the freehub is most likely frozen due to old grease and or water which has gotten inside the hub. Same advice still applies though, you will need to overhaul it and get new grease in there or just buy a new one.


I got a leak on my shimano 105 R7020 STI

According to the ST-7020R exploded diagram at
https://dassets.shimano.com/content/dam/global/cg1SHICCycling/final/ev/ev/EV-ST-R7020-4341C.pdf
That part doesn't exist as a removable part, hence why you need to confirm your exact shifter part number.

For completeness - the dealer manual is at https://si.shimano.com/api/publish/storage/pdf/en/dm/RADBR01/DM-RADBR01-07-ENG.pdf
and a browse through shows no mention of removing that plate.


Assuming:
- the axles are of a width that they will fit the dropouts and can be tightened down enough to prevent the wheels from falling off
- You don't have brakes or a drive train to consider (which you said you didn't in the comments)

...then why not? The bike will look a little funny, but the kid will dig it.


Is it normal to stop so much because of thighs burning?

More than likely it is normal and frankly your legs probably aren't used to it. 17 miles is a long way for a beginner so I would pat yourself on the back for that.

You may also benefit from a proper fit from a bike shop. As a lot of beginners either have their seat too high or too low which can limit your power and actually cause you to tire quicker, although a fit takes a lot more into consideration that just that. Either way it would probably be worthwhile to at least look up a good guide and check your posture, it can make a big difference.

Regarding your age, I am 32, and know several people in their 60's that could leave me behind going up hill (or anywhere) with ease.

I am in okay shape, and have been riding off and on for several years and still have to stop from time to time. It does get better though.

You may also take a look at your diet and pre-ride foods, it is also important that if you are going on a long ride you take some snacks for along the way so that your body has some fuel to burn. Eating 30 minutes to 1 hour before a ride vs not eating at all can make a monumental difference.

Bottom line you have made a healthy choice and a fun one to improve your own health and way of life! Keep at it and don't give up or feel bad if you need to stop and catch your breath from time to time, the most important thing is you are out riding!


Does anyone know what brand and model is the bicycle in photo?

It's a 1961 Hawthorne Twin Bean Tank Bike sold by Montgomery Ward.

1961 Montgomery Ward Christmas Book page 180
Here's one in the wild

ratrodbikes.com
The model was sold in 1960 and 1961. The 1960 version has slightly different graphics.

The Hawthorne bikes were made by CWC (Cleveland Welding Company) the maker of the Roadmaster bicycles) since 1934, and were distributed by Montgomery Ward across the country.
american-vintage-bicycles.com


So it turned out that my tires were really old and rubbish, and had a few bits of gravel, glass etc embedded in them which were puncturing the new tubes every time I changed them.  I bought some new tires (puncture resistant ones) and I haven't had an issue since.  Thanks for all your advice everyone!


How to adjust brake level movement on hydraulic brake?

Aurigas don't have bite point adjustment. For the most part it's a feature found only on some upper end hydraulic brakes.

The rear brake being a little softer and longer to engage is normal since the line is longer. But if it's more than a little, that can be a sign of other problems that bite point adjustment wouldn't help with anyway, like air in the line or a piston movement problem. If the rear pads are getting worn out that will also contribute.


Can an odometer (magnet) be attached to an exercise bicycle crank arm (not the pedal)?

For your requirements this would work fine.   The speedo readout would not reflect a real-world value, but for comparing efforts on the same bike it would be ideal.
I'd suggest the lowest priced wired Cateye bike computer (velo9 or similar) because it lasts years on a battery.  I've had cheaper bike computers, and they can eat batteries in a few days.
For fitting, I'd try mounting the receiver end of the wire somewhere near the L of Landis on the housing, using double-sided sticky foam tape.  Secure the magnet on the inside of the crank, such that it won't get banged by your shoe.
Great work for finding a solution.


The word "compact" can be used in two contexts, both separate from each other.

The first is to do with the geometry of the frame. This is basically where the top tube is sloped rather than level. As is often the case, Sheldon has a good description including the whys and wherefores.

The second is to do with the gearing, in particular the number of teeth on the front rings. This is covered in a previous question: Number of gears for a racer. (Its covered on Sheldon too, close to the previous link.)

If you weren't already aware, Sheldon's site is a superb reference for all things bicycle.


Replacement Rear Axle Sizes on Vintage Bike

If the cones are pitted, the bearing surfaces inside the hub shell may well also be damaged. As the rim is not particularly valuable, your local bike shop may be able to sell you a complete replacement rear wheel to suit the screw-on 6-speed block you have.
If you really wanted to only replace the axle, by 1990 I would expect a non-vintage hub to be using metric dimensions, so it's very likely it uses the most common size.


Old Sears Simpson bike bottom bracket replacement

It turns out that there is a technique that involves using a bolt, a bunch of washers and a screw with a nut that can be purshased from just about any hardware store. The technique is documented here.

I tried it out and it worked like a charm. Even then, it's the amount of leverage you gain access to that makes all the difference(used a cheater bar for more leverage). The cap(drive side) happened to unscrew clockwise, same as the other one(Once I had the non-drive-side cup removed, I slid my finger along the threads of the drive-side around the inner perimeter to see if my finger was being pulled inwards or outwards to figure out the threading).

I also struggled because unbeknownst to me, my dad literally screwed a screw through the frame to lock the cup on the non-drive side. I used pliers to twist it out.

This was a satisfying experience.


How to equip a bike to avoid parts being stolen

There are various proprietary brands of security hardware such as pinhead and pitlock.  I use the former on both my bikes, for the wheels (QR and nutted), headset, saddle and seat post. Pinhead fittings at least are stocked both side of the Atlantic (I suggest with either that you buy a spare key at the same time).

The bike I keep outside has further features: wherever possible, accessories (such as the bottle cage and pannier rack, even the bracket for a removable light) are attached using anti-tamper torx screws (picture is of the tool). The tool is readily available if uncommon, so it is mainly a deterrent against casual thieves but so far so good. I had a whole front light attached this way and half the light was taken/vandalised shop that may give you an idea of the limits to this approach.

You need a good locking strategy. I use a D-lock through the back wheel, both chain stays and a bike rack, work a separate cable lock through the front wheel, front triangle, helmet and rack. This means both wheels are protected by locks not just security fasteners.

Consider not always locking the bike on the same place. I have a choice of racks outside the station overnight, but lock it inside the station for weekends or longer (it takes long enough getting it out of the station that it would be quicker to walk than do it every day).

I use a cheap bike for this, which is a further deterrent. We have questions here about how to make bikes (and by extension their components) unattractive to thieves.

I have failed to find lights etc. designed for secure mounting, instead the manufacturers have gone the opposite way and made them easy to remove.  I've had some success modifying clip-on lights to fit with screws (e.g. glue the 2 parts of the clip together)


Aspects for choosing a bike to ride across Europe

There are a few factors to consider.
How much luggage do you want/need to carry?
Stopping in hotels, or carrying a tent etc?
Is speed/efficiency important?
Can your flexibility/core strength support long periods in a more aerodynamic position?
You certainly can't go wrong with a traditional touring bike like the ones you mentioned, but there are other more modern and lightweight options available.
My personal preference for such a trip would be a race orientated gravel bike (like a Cervelo Aspero for example) fitted with bike packing bags. Fast, efficient and fun to ride, but with features that are good for touring like extra bottle cage mounts and top tube bag mounts.
But that is my preference for how I like to ride - others would have different ideas and priorities.  The best we can do is give ideas/options, but only your own preferences and experience can tell you the right answer for you.


Does a typical floor pump have an integrated one-way valve?

There is a valve in the floor pump, yes, so it is supposed to press in the presta valve the whole time it is attached to it.

I too have seen the problem you refer to in the comment on @Useless's answer - diagnosis has always shown this to be down to the presta valve either catching on the side of the pump fitting or just being stiff and refusing to budge.

A simple solution I use is to give it a quick press with my finger before using the pump, just to ensure it moves cleanly and isn't stuck.


Fixing pinches with latex-based sealant?

Latex based sealants are great at fixing the sort of small holes that you'll get from thorns and glass. If the hole is too big, then all of the sealant will just rush out with the air in your tube. Pinch flats tend to make a big enough gash in the tube that sealant is useless.

People will often talk about using sealant to avoid pinch flats because they're talking about an entirely tubeless system. This means that the sealant replaces the tube altogether, leaving nothing to pinch at all. Unfortunately this can't just be done on any setup with any old tyre, making it an expensive venture if your wheels and tyres aren't already tubeless ready.

Once you've fixed the flat, the best solution (without spending $$$) to avoid pinch flats is just to run higher pressure in your tubes.


What is the proper way to tighten dual bolt saddle rail clamp to stop rail slippage?

A good rule of thumb when tightening down any multiple fastener connection would be to finger tighten (if possible) each bolt until snug, them apply a tool and alternately tighten by stages slowly reaching the torque spec per bolt. This should provide a more even pressure distribution per side. NEVER fully torque one side while the other is loose, always alternate sides with even torque until THE SPECIFIED TORQUE IS REACHED. DO NOT UNDERTIGHEN, OR OVERTIGHEN. There is a little tolerance built-in to the spec (although possibly not shown (e.g. 10 Nm +/- 1 Nm). I do not have information on the hollow Ti rails, but I would think that they are engineered to handle the clamp pressure. You might reference the saddle manual to see if there is a recommended max torque the rails can handle. Due to shifting weight of the rider and slight flexing of the saddle during riding, I recommend that the torque be rechecked after the first couple of rides to ensure everything is still within specs and check that the saddle position has not shifted (I mark saddle rail orientation once comfortable, front-back and angle up/down to allow for easy verification/resetting).

Good Luck,
HPL


What Supporting Muscle Groups Should Be Strengthened?

What supporting muscle groups need to be strengthened?

All of them! Cycling is a full body sport, despite what some people will say. Ever ridden a long ride on a road bike? You may have soreness all the way from your neck to your toes. Some of this can be from poor bike setup, but that's another topic entirely.

The major muscles are obviously going to be legs, back, and core as these are the muscle groups that support the motor (making the bike go). Next up is your upper chest and back, shoulders, and arms which all support the driving (telling the bike where to go). If you ride on bumpy roads or trails you know how much your arms get beat up!

In what order of priority should those muscle groups be addressed?

Do not train exclusively one set of muscles over another, that's just generally bad practice. You should look to strengthen all your muscle groups. Now, if you have a specific objective in mind, like "I want to climb hills like a mountain goat." you may want to start by targeting your weak points (leg power) or strengthening the needed portion (hamstrings, quads, calves). For all around cycling fitness, don't just work the "mirror muscles" aka the big ones that have lots of definition. Supporting muscles are what keep you from getting injuries in your joints or excessive stresses in your major muscles, so don't neglect those.

What is the optimal strength to maintain for each of the groups? By optimal strength I mean how much effort (10min 3x wk for example) do they need? If it depends on how much biking then please answer for a nice spectrum of distances such as 60mi/wk, 150 mi/wk, 300 mi/wk.

Again, this depends on your goal. If you're a weekend warrior looking to do some nice leisurely rides around the lake or through town, you'd probably be OK working out 2-3x per week for 30 mins doing basic bodyweight strength training. But if you're wanting to prepare for a bike race, triathlon, cross-country epic, you'll want to do 3-4x (or more) for 45-60 minutes a week to not only maintain, but develop and improve your strength.

Cross training (running, swimming, lifting, etc.) can be very valuable to any athlete from amateur to pro. Look at various programs and find what works for you. Body types, goals, and external limits can help you plan the type of program that will work best for you.

*Note: I'm not a certified/licensed trainer/doctor/physician but I've been doing sports since ever of all kinds, and currently race amateur class mountain bikes.


As for sheer maneuverability, seat tube angle may in some (rather extreme) cases affect wheelbase, which affects stability at variety of speeds. Also seat tube angle will have some minor effect on the position of rider's centre of gravity making it slightly easier to descend with smaller seat tube angle... I guess it would be an unnoticeable difference though.

But main aim of angled seat tube is above all to make pedalling more correct in a biomechanical way, thus more efficient..... and making it possible for a rider to reach the ground while still being on the saddle, say when they're stopping. For the right distribution of stresses within your joints you need an angle adjusted to your body - people with longer thighs will need smaller angle. In general too low angle encourages lower cadence and more forceful pedalling which isn't very good for your joints. What's interesting is that it doesn't work the other way round - it's possible to ride relatively safely with very high angles - it's usually 78-80 degrees for TT bikes. (I meant to put an article titled "Myth of K.O.P.S" for Sheldon Brown website, but the link doesn't seem to work)

Here is the link to Sheldon's Myth of K. O. P. S. (knee over pedal spindle) article.

Seat tube angle can be quite well made up for with fore-aft saddle position, so 2 degrees in difference can be easily neutralised. And the differences in angles between sizes may come from various sources:

it could be forced by the design, for example to avoid some weird top tube length or too short distance from the crank to front wheel.
it may also be a form of adjusting the geometry to body proportions of riders of different sizes.
or it could be done to lower the centre of gravity for a large rider, that for large sizes is pretty high anyway.

Or it could be a mix of the above, we should ask the designers.


That chain is sitting quite well on the front ring, almost perfectly, as far as can be discerned in the photo. In particularly, it doesn't appear to be elongated at all, which is usually the telltale sign of chain wear. When a chain is elongated, you can easily tell on the front ring, because it has so many teeth that the cumulative error of the elongated links causes it not to sit properly all the way around the ring.

I'm guessing you (or a previous owner) replaced the chain, possibly more than once, but didn't swap the rear cog at the same time.

That's a mistake.

Chains elongate as they wear, and at the same time, they wear the cog, and are worn by the cog. A chain which wore together with the cog might not skip, yet if you change to a new chain, that chain will skip on that old cog.

I've never been able to change a chain alone, without skipping cogs. (That is, the few times that I tried, before I stopped doing that).

Do check the tension! But note that chains don't have that much tension in derailleur systems (just that tension provided by the tension wheel) yet they don't skip, when in the proper condition. Basically there has to be ridiculously low tension. It's hard to tell from your picture, but it does look as if the chain is coming from the ring in a fairly straight line, no sag. Anyway, when you're pedaling hard, there is tension in the top section of the chain, between the ring teeth and the cog. Under this tension, they stay engaged even if the returning-to-ring section of the chain is sagging. If you don't believe me, think about this: when you remove a cassette from a hub on a derailleur system, you open a lock ring, for which you require a chain whip to hold the hub steady. That chain whip is just a piece of chain connected to a lever, loosely wrapped one of the cogs in the cassette: no tension in it at all, other than the applied tension. Nothing pulls on the unattached end of the chain to keep it wrapped around the cog! Yet, it grips tenaciously, enough to remove a stubborn lock ring. I've never had a chain whip skip, even when ridiculous force was needed (enough to break a spoke).

Get a new cog!