How do I reassemble this Quando rear hub?

How good does this have to be?
If you are going to use this as daily transportation to work I'd want the correct dust seals and I'd go with a different wheel.
If this is a klunker you don't really care about I think you can experiment and arrive at a workable assembly.

Here's my best guess at something workable.
Parts "F" and "E" look like dust guards. Sometimes they press fit into the hub AFTER the bearings are greased into the races.Sometimes, like in the picture you linked, they are attached to the cone. They usually match so I'm not sure what to make of the rubber seal. See if it will press into the hub on one side or the other.

With the bearings in and the dust covers on (assuming they fit into the hub)
And, with the freewheel off - if possible.

Thread the thin cone "D" about 1.5 inches down the axle.
Thread locknut "B" after the cone until it hits the cone
Tighten the locknut against the cone but only snug - not tight, you'll probably have to move it later.
Insert your axle assembly into the non-freewheel side
Thread the fat cone onto the freewheel side of the assembly until it just touches the bearings.
Slide the spacer "H" onto the freewheel side
Thread the other locknut "B" onto the freewheel side
Play with the left over washer "G" and see which side it works on. My guess is that it will go on the freewheel side. I'd put it between a lock nut and the spacer if it helps spacing on the freewheel side. If it helps the spacing on the non-freewheel side I'd put it between the cone and the lock nut.

Now you play with the spacing so that the wheel is spaced in the frame, the freewheel spins and the chain has enough room on the smallest freewheel gear to clear the frame and the axle sticks out about the same amount on each side.


Alternatives to trailers for transporting young children

Followed some links from your links and found the actual text of the law, which summarizes the law as:

  Prohibits person from carrying child
  under six years of age on bicycle or
  in bicycle trailer.

Elsewhere in Oregon law, a bicycle is defined as:

  [a human-powered vehicle] designed to travel with not more than three wheels in contact with the ground.

So a unicycle, bicycle and tricycle are all covered by the proposed law.  There's also a wheel-size provision in the definition, which makes me suspect that too small of wheels or 4 of them puts you in a category like skateboards that probably aren't allowed on the road.

So I think you simply have no solution if that law passes as written. Everything I've ever seen for using a bicycle to transport a child constitutes "on bicycle" or "in trailer".  Even if you devised some clever sidecar or push-cart mechanism to get around the letter of the law, I doubt that would work.

But just in case it's useful, there was an earlier question along these lines that I think covers all the answers you could be looking for: Recommendations for Transporting Twins On The Front of a Bike

Basic summary:

Coolest option is a bucket bike (long wheelbase with a big box built in). Common in Netherlands, rare in the US.  Search for "cargo bike" in your area (I know there's bikes of this type made in Portland, OR)
Next best is probably a long-tailed bike, such as an extracycle, especially if you can get seats designed for that use
There's child seats that mount on a bike rack behind you
child seats that mount on the handlebars in front of you (you could combine this one with any of the other options)
Trailers are pretty darned good for carrying children.


What do you call the plastic bit that mounts brake cable housing to dedicated frame mounting spots?

Jagwire calls these "Hose Guide for Frame Loops".
I've also found these under "Cable Guide" on Amazon.


Seems like you have two options. I'm not sure this is your exact model but the broken piece should just unscrew.

Unscrew what's left and epoxy it together apart from the internal workings.
Buy a replacement cover. I couldn't find any online shops selling replacement covers, but a call to Shimano* will probably net you the exact piece you need. You'll need to know the model number which should be displayed somewhere and look like SL-xxxx. I can't imagine a new one will be more than $20.

*Shimano American Corp. (949) 951-5003


How do i figure out the maker of my bike?

90% chance its a generic BSO.  If you have a distinct feature, post a photo and someone might recognise it, but...

Why do you want to bother identifying the maker?  You already have a frame that will have certain dimensions or bearing sizes.  There's little if anything to be gained from buying parts from the manufacturer.

Your best tools are likely to be a vernier caliper and a thread gauge, to find specs for parts you might need to make frame into a whole bike.


How can I fix my rear derailleur's B-tension adjustment?

If I understand you correctly, you don't have a B-Tension issue. B-Tension sets the clearance between the upper derailleur pulley and the chain, and should not be used to add spring return force to a derailleur.

In this case, I believe that the derailleur pivots are in need of cleaning and lubrication, and I would start there.

If that doesn't fix the issue, you can look at replacing the derailleur return spring (#2 in photo)behind the fixing bolt of the derailleur and/or the cage spring (#1 in photo)between the derailleur body and the derailleur cage.

Ultegra 6700 RD Manual

Exploded View PDF


You are sort-of correct in the assumption that there is a 11-34 cassette in the Tiagra range means it is compatible with a Tiagra rear derailleur, but it's actually only the long cage (GS) version that will take a cassette of that size.

Shimano has a nice set of pages that detail compatibility within a groupset, here's the Tiagra page.

The Opus web page for the Spark 2 shows it has a Tiagra 4700 series rear derailleur. It's not specified which cage length but the picture clearly shows a long cage (GS) version.

You can also check the RD-4700-GS spec page and see it is compatible with a 11-34 cassette.

You also need to check that the derailleur works with the FSA crank chainring sizes, which are 48-32 assuming you have a size S frame or larger.

Maximum front difference is 16 teeth - you are good there
Total capacity (the difference between the numbers of teeth on the largest front ring and rear sprocket, and the smallest front ring and rear sprocket) is 39 teeth - you need 39 (34+48-11-32), so again you are good.

If decide to fit the bigger cassette you will need a new chain as the required chain length will be longer (chains should be replaced when cassettes are changes anyway). You will probably also need to adjust the derailleur b-screw which controls how close the upper jockey wheel rides to the cassette sprockets.


I have to say this first: riding a bike when part of the brake system is not assembled as it is supposed to be is potentially dangerous.

The brakes may seem to work fine but if the housing or adjusters are not seated properly they may come adrift and leave you with a non functioning brake.

Brake and shifter barrel adjusters are necessary to fine tune caliper engagement and shift indexing. I do not recommend removing them as one day you will wish they were there.

Backing a barrel adjuster all the way out will not strip the threads as there is no thread engagement therefore no damage to the threads. They can be a pain to get back in though. If you disengage the cable at the caliper temporarily so there is no tension in the cable it may be easier to screw them back in. Alternatively have a local bike repair shop sort it out.

You may also want to check out some online resources on proper brake adjustment. Park tool has a particularly good set of videos on their YouTube channel.


Are there standards for tubeless tires/rims?

Basically at this point there's broad cross-compatibility in practice  among the tubeless compatible me-too type "systems" by way of everyone just copying each others bead and bead lock designs. A de facto tubeless standard emerged from all of it that more or less just works.

UST is an exception in that it's a clearly defined system in terms of the dimensions of both the rim, the bead, and other specifications like how the rim has to be airtight by itself. But UST has other issues, namely that for all the trouble one goes through to adhere to it, you get a heavier tire and no puncture-sealing if you run it without sealant, so it's pretty far out of favor. Using non-UST tubeless tires on UST rims and vice versa set up tubeless usually works fine, but requires sealant.


First time to install Clincher Tire to Rim

Congrats on taking the first step to DIY.
Rim tape is used to make sure the inner tube does not get punctured from sharp edges where the spoke connects to the rim. Also, if your wheels are rim brake alloy wheels, Rim tape can act as thermal insulation to protect the inner tube from exploding under extreme braking. Since your wheels are Carbon and if your wheels do not have any of those spoke edges exposed in the rim bed, then no you do not need it and it would be just additional weight.
I suspect perhaps those wheels may have something already in place that makes the inner portion smooth and thus would make rim tape redundant. It never hurts to call customer service too to double check, but if you are not seeing an exposed connection point for each spoke, then you probably are good.
Regarding installing a new tire, I would say take your time and have good pair of tire levers. These videos should help

The hardest part is near the end when lifting the last portion of the bead into the rim. Note the technique Calvin/GCN uses with the levers as that is the correct way to use them. Also as a side note that was the easiest I have ever seen a road tires slip over a rim in these video. I ride on Continental GP 5000 clinchers and the last part of the bead is not usually that easy to lift over the rim (i.e. expect to put some force to lift the bead into the rim bed), which in my opinion is a good thing.
Also, after you are done mounting the tire make sure you inflate it and ensure the bead + tube is inside the rim all the way around. Oftentimes, I will inflate the tire to max rated pressure on the 5000s that is like 110 psi for a 28MM and that forces the bead into the edges of the rim. After that I reduce pressure to what I ride on and that should be it.
Of course make sure you put your wheels on the bike properly using your quick release, etc.
Wear your riding glasses or a pair of safety glasses (my pref if I do not have a flat on the side of the road) just in case a tire lever or something goes flying accidentally or snaps.
Hope that helps.


Imprecise shifting on a Shimano 9 speed set

There is no compatibility problem.
If the direction you have to shift twice in is downshifting (pulling cable, going to bigger cogs), that can indicate not enough cable tension. If it's upshifting, it can indicate friction in the cable/housing.
It sounds a lot like one or both (could be both) of the above are true. Misalignment in the derailleur hanger can also add to the finickiness of the adjustment, i.e. making it harder to get the chain to shift right and then stay in place without the ghost shifting. Excess pulley and pivot slop in the RD can also contribute to sluggish shifting. So can a B-tension screw that's too far out.


How to make a kid's bike easier to pedal

Children's bikes are usually designed with easy gearing appropriate to children.
As Chris H said - they are not usually assembled by people who care that a bike is assembled correctly. From the factory it seems like everything is always too tight.

My guess is that there is something that can be adjusted to make things better.
Flip the bike over so it's sitting on it's seat and handlebars.
Pedal the bike and see how it feels. This will give you a baseline to know if you've made improvements as you adjust things.

Things that make a bike hard to pedal:

You are right to ask about chain tension. If the chain is tight it will be hard to pedal. You may be able to loosen the chain a little and feel an improvement immediately.
Rear wheel hub adjustment. With the brake disengaged the wheel should spin freely. If it does not you'll need to loosen the bearings on the hub.
Crank bearings. If the chain tension is OK slip the chain off the chain ring and feel how easy the crank is to move. If the crank is stiff you'll need to loosen the crank bearings.

Edit:
Adjusting Chain Tension
(When I started writing this I thought it would be a few steps - but it kept getting longer...)

There is the easier way and the slightly harder way to adjust chain tension.

The Easy Way

Remove the nut on the chain side of the wheel that holds the training wheel.
With the training wheel off loosen the nut that holds the wheel on.
At this point you may be able to squeeze the chain and get a little slack in the chain . Since you are only shifting one side of the wheel adjusting this way can put the wheel off center in the frame. That's OK as long as the tire does not rub on the frame. If you are able to get enough slack in the chain to smooth out pedaling without having a tire rubbing on the frame you are done - go to step 4.
If the tire is rubbing skip step 4 and to "The Slightly Harder Way" step 1.
Note: if you wanted to tighten the chain pull the right side (right side of the wheel looking at the wheel from the chain side) of the wheel toward you.
Re-assemble in reverse order.

If the tire is too far off center
The Slightly Harder Way (continuing from the previous steps)

Get the chain tension where you want it and tighten the nut that holds the wheel. This will set your chain tension.
Remove the nut that holds the training wheel on the non-chain side.
With the training wheel off loosen the nut that holds the wheel.
At this point you may be able to center the wheel and re-tighten the nut. If the wheel won't center - step 5

Picture of the non-chain side and the brake strap after the training wheel is removed.
 1. Loosen the screw that holds the brake strap (you may need a wrench to hold the nut on the other side of the screw).
 2. Center the wheel
 3. Tighten the nut that holds the wheel
 4. Tighten the screw that holds the brake strap
 5. Put the training wheels back on


Can I add a 11-40 XT or XTR rear cog to a road bike with Di2?

I see some potential issues, but can only answer to some of them:

Rear derailleur maximum cog capacity. RD-6870 supports up to 32 teeth, so you'll have to get RD-M8050 or RD-M9050 for anything bigger than that.
Road/MTB DI2 capability. According to this article, 6870 and M-8070/9070 should be compatible.
Rear derailleur overall capacity. I'm not sure how 8070/9070 will handle road double up front.
Freehub body width. Shimano 11-speed MTB cassettes are narrower than 11-speed Shimano road cassettes by about 1mm. Make sure you've fitting a spacer.


Shimano 11 speed road cassettes are wider than previous models, so you most likely will need a wider freehub body. In some cases it can be bought separately, but given that you have 9 speed at the moment, I find it unlikely, so add an 11 speed Shimano road rear compatible hub to the purchase list.


How can I get started building a bicycle?

My main resources for pretty much anything include:

Sheldon Brown
In particular:

sheldonbrown: how-to-fixed-conversion

sheldonbrown: fixed-conversion

Loads of general wrenching info at
Park Tool

And of course a friendly local bike shop.

Look out for a bike co-op or skills-sharing non-profit/community organization. They may run classes and provide parts and tools.


Given the limited info in your question, this answer has great limitations as well.
Preload adjustment is simply a mechanism that adjusts pressure on the spring coils. Increasing preload puts pressure on the spring, slightly reduces the distance between the coils, and results in a firmer/stiffer suspension.  The spring, under increased tension, requires more initial force to respond.  Increasing preload, reduces the amount of sag.

Much of the opposite happens when preload is reduced. The mechanical mechanism that puts pressure on the spring is physically raised away from the spring (everything is still in physical contact), the spring's coils relax a bit, and the suspension becomes more plush: less force is required to move the suspension.  Sag increases.

You state a desire to soften the suspension and reducing preload will accomplish this to some degree.  Try reducing the preload--probably all the way in your case as a light rider.  However, as alluded to in the comments, a lighter (or heavier) than average rider may need a different spring (less stiff in your case being a lighter rider).  In other words, you'll replace the current spring with a different one.   What I think in your case is that since you couldn't find any info online and the spring suspension fork carries the same branding as the bike, it's likely to be cheaply made, difficult to find parts--especially one offering choices of springs of various weights---and essentially not worth further time and cost to change out.


Brake cable housing will not stay in barrel adjuster on lever

The brake cable housing is a slip fit into the brake lever barrel adjuster and cable guide bosses at various places on the frame (for the rear brake) or fork (for the front brake).

The housing is prevented from coming out of any of the mounting points by the cable having not enough slack for the housing to slide along it enough to pop out.

General process is to follow the housing from the brake lever to the caliper and you will probably find the housing has come out of a frame or fork mounting boss, or the cable is detached from the caliper, or the cable just has too much slack in it. I assume that is the front brake which goes directly to the front v-brake caliper. I'm guessing either the metal pipe 'noodle' that the cable runs through has come out of the caliper or the cable has come loose.

Park Tool has a good page on v-brake (or linear brake) service and adjustment that you can refer to. https://www.parktool.com/blog/repair-help/linear-pull-brake-service.

BTW, the cable looks like it is fraying - there's a strand visibly loose in your pictures. You should replace the cable. The front brake cable failing is obviously quite dangerous.


What do the conical springs in quick releases actually do?

The springs help you center the skewer in the dropout which makes the wheel easier to install. You don't need them for the QR skewer to work, but they're nice to have -- if they're damaged or lost, don't worry about it.

Once the wheel is on the bike, they don't do anything.


Slipping aluminium seatpost in aluminium frame

I had an exactly same problem: Ritchey WCS seatpost, Merida frame (both alu alloy) and a lightweight clamp, like in @Frisbee's answer. What I tried:

Beefy clamp with various torque settings. Didn't help at all.
PVC tape. Helped, but didn't last long.
More torque on a lightweight clamp. I snapped it in half with only 6Nm.
Hair spray. To my surprise, it worked and seatpost stopped slipping, creaking and annoying me.

I've switched to a CF seatpost since then, same problem occured, but hair spray come to rescue again. No slipping for months.


No more than any other full floater.

The bearings are sealed so they should only need replacing every few years or so.
The bushes usually last a year, but you can feel their state by any 'knocking' when you take pressure off the wheels, or by trying to bend the swingarm laterally.

Stripping down the frame and regreasing the pivots won't do any harm, but certainly isn't necessary - I find it just makes getting the bearings out easier when they need replacing.  Admittedly, after a wash I put a few drips of thick 3-in-1 oil inbetween each pivot - truthfully I have no idea if this does anything, but it probably stops water sitting in the bearing cavities for long periods.

As for any other sealed bearing do not spray GT85, WD40, or any other water displacing fluid into them.  They come pre-greased, and if the seal fails, it needs replacing.


Yes, that's a proprietary system.

That said, front racks and baskets that mount to the head tube are very stable. The rack basket doesn't flop around when parked and it doesn't affect steering when you're riding. Unfortunately there aren't standard head tube mounts (Brompton has one design for example). Until a standard emerges, this is the best we can do with. The only downside aside from the price is that you can't easily hang large front side panniers because they would interfere with steering.

Most off the shelf front baskets and pannier racks mount either to the handlebars or to the pannier mounts on the front fork and suffer from said mentioned floppiness.

Tldr: it's proprietary but worth shelling out for.


Can the brake levers be moved from the side to the top of the handlebar?

Not really. The levers in the second picture are commonly called "interrupter" levers, and are usually used in addition to the levers you've already got.

I think you'd find that if you simply tried to relocate your existing levers, they wouldn't fit against the tops of the bars very well, and the way the levers are curved would cause them to bump into the handlebars before you had fully depressed them.

You could replace your current levers with interrupters (at least some interrupters are designed so they can be used alone). I'd advise against that: riding from the "tops" of the handlebars can make handling a little dicey, and this would lock you into braking from a less-controlled position. You can ride on the brake hoods or the "ramps" just above them and still apply a fair amount of leverage to the brake levers while being in a position that's reasonably comfortable and controlled.

If your bike is the one shown in the top picture, you can also raise your stem. I think that if you give the forward position a chance, you'll adapt to it. If not, you can replace your handlebars with flat bars (you'd need new brake levers for that as well).


How hot / humid does it have to be for cycle touring to become unenjoyable?

I was out in 28C and 50% RH yesterday, not touring, but comparable: a century (160km) at a fast touring pace, laden by the standards of a day ride, and with a brief swim break in the afternoon.  It was hard work (much harder than it would be 10 degrees cooler), but still enjoyable.  You have to plan on being able to obtain water. I got through about 4 litres, and have reached 9 litres in the past on hot 200km rides.  Especially for multi-day riding, like touring, will your appetite survive the heat? I tend not to eat enough on a long day's ride, if it's over about 25C by lunchtime, though if you can buy ice cream...
Road conditions matter - dropping into a wooded valley from an exposed hillside is a great relief.  How likely is shade?
If you can avoid the hottest part of the day, that helps, but many areas lose heat slowly, so avoiding the heat means doing most of your riding in the morning, resting or sightseeing in the afternoon, and maybe doing a little in the evening.  But does this fit with your target daily distance?  Is there a shady (and pleasant, with food/water) place to rest out the heat?
Clothing is tricky.  Clothing for sun protection keeps the wind off, so even if it didn't make you hotter standing still, it would going along.  Arranging clothing to allow more airflow means it flaps in the wind and makes you work harder.
Guessing at your route as Sydney->Brisbane (but not along the coast), and quickly checking the map, the road passes through plenty of towns, so places to stop even if most are small, however street view suggests you'd be riding in unbroken sun for long periods - I've been known to stop and drink under every rare tree in that case.


Are collisions with animals something to be worried about when cycling in the country?

Sure, there have been cases of hitting an animal in the day or night. Here is an article of a cyclist being attacked by a moose, for example.  In addition, you need to worry about road hazards since you won't see them as early.

Obviously, the amount of hazard depends on the particular location, but you should have good lighting and reflective gear at night as well as be prepared to slow down and stop if necessary. If the area is known to have hazards, it may be advisable to go a little slower so you can stop quicker if needed.


Why is this rear wheel not aligned with the frame?

One visible issue is the quick release skewer spring on the drive side. See how it is visibly stuck in the drop out, where it shouldn't be. This means it is facing the wrong way round, so you need to remove the wheel, swap the spring(s) round the right way and reinsert the wheel. They are conical, and both 'point' inwards to the centre of the wheel.
Such a little error can cause a noticeable skew of the wheel, so I would think this will solve the problem. Note how the tyre is skewed off from the bike centre line.
As Nathan notes, removing that spacer will have had an effect on the wheel dish. Check the spacing of the frame and the wheel hub width (O.L.D.). I'm not sure if the wheel was too wide originally or if the spring originally caused the problem you were trying to fix. You'll either need to replace the spacer, or re-dish the wheel to get things just right.


For what it's worth - the best answer I've been able to come up with/figure out is that when I was torquing the bolts down I might have been putting force on both the crank arm and the torque wrench and maybe doubling up on the force...


Can I use a mountain bike to go bike touring?

You certainly can use a mountain bike for touring, and many people have done so. They have suitable gearing for climbing and are generally stout enough to support the weight and abuse of loaded touring (caveats below). However it is worth noting the differences between a mountain bike and a touring bike, and consider these factors for your trip:

MTB frames usually have a more responsive geometry with shorter chain stays and wheelbase, steeper steering angle, and a higher bottom bracket. These features make a MTB more nimble on trails, but less stable when loaded and traveling at high speed.
MTB frames are usually aluminum which often doesn't provide as much vibration dampening. Aluminum is also more prone to structural fatigue than steel and with many miles can crack or worse. Carbon fiber is even less suitable than aluminum and should never be used for loaded touring for safety reasons (until a carbon frame purposefully built for touring is available).
MTB frames with rear disc brakes often do not have rack mounts; the usual location of a rack's lower connection point conflicts with the brake calipers. Old Man Mountain makes touring racks which fit bikes with this limitation.
MTB frames usually have fewer water bottle mounts.
A MTB with suspension, unless locked-out, will decrease peddling efficiency. Unless you're touring on very rough roads the suspension is just added weight.
A MTB's straight handlebars do not provide different hand positions for avoiding hand and arm fatigue, and potential hand nerve damage from extended compression of the ulnar nerve.
Smaller wheels, such as the 26" wheels commonly used on MTB, are stronger than larger wheels such as the 700c of road and touring bikes. These wheel's replacement parts (tires, spokes, and rims) have also traditionally been easier to find in less developed countries.
MTB tires with aggressive tread can have lower rolling efficiency than slick tires, and at least contributes to a noisier ride. Tread can, counterintuitively, decrease the traction of the tire on a smooth road.

Despite these differences, a MTB can be a very suitable touring machine. Some of the best touring options are early (1980s–90s) rigid (no suspension) steel frame mountain bikes, which can be found second-hand very inexpensively. Some MTBs may even be converted to use drop bars with road brake levers and bar-end shifters (you'll want to get an expert opinion from a local bike shop as some MTB brakes or derailleurs aren't compatible with road brake levers or shifters).


Yes, do not use them here.

They will be impossible to get to full tension without windup on a rim even remotely as stout as that. What's likely to result is a wheelset that could have been rock solid will have constant issues with spokes going loose.

If you want to run fancy spokes, Supercomps are about as light as make sense here, and the 1.8mm tips give the advantage of much more breakage-resistant nipples for a given material choice, which is a nice thing on a disc brake touring bike getting off-road use.

Normal 2.0/1.8 would be the more standard choice. They make it easiest to deal with windup and get a stable build.


As far as assisting at race pace - a cadence of 90 or 100 is not a limit for an electric motor designed for it. With the dollars involved in cycling generally, and at elite sports specifically, I do not see any barrier from an electromechanical perspective. Most importantly for an elite rider, the motor can be optimised for a cadence between  85-95 - a very small range.

I would be less concerned about a 200W Assist over a short time, as it would be rather obvious, than a net (factoring in extra weight) 20W or 50W assist over the duration of a tour. Imagine if you could give a rider a drug  that instantly gave them and extra 10% output over an entire tour? This motor could be small and hard to detect. Its heat signature would be tiny. A physical bicycle inspection would be needed.

Current battery technology limits the capacity available without obvious signs - physical size but also the weight would make the bike move differently to normal. I am sure an experienced observer would spot it. However, research into battery technology is progressing very quickly. Its foreseeable within a year or two batteries with 10x capacity for no weight or size gain will be possible. recharge times are plummeting to measurements in minute to full charge.

So should they be worried Absolutely- today I think the risk of you or me doing something and being caught is high, the hardware is too big and bulky and obvious. A simple weight test of the top riders bikes would suffice. However the dollars involved at the highest level, and the scale and length of time the cover ups and secrecy around Lance Armstrong's drug use were able to continue do not preclude a team spending a large amount of money  into secret commercialisation of research results.

Within 10 years, I believe the average road or MTB will have an electric assist option as it filters up from the commuter/casual market into main stream.  From there, its a tiny step into the race scene.


Are bananas still a good food to carry when cycling?

There is an interesting Q&A on independent.co.uk (though it dates from 1995) talking about bananas and tennis...

  Q. Witnessing players at Wimbledon
  chomping their way through pounds of
  bananas between games prompts the
  question: who began this sporting food
  fad and are there sound nutritional
  reasons for the players' preference
  for bananas to other fruit or food. In
  what other sports (leaving aside lunch
  and tea breaks in cricket) do the
  participants eat during the course of
  play?

  A. The sporting fad for bananas was
  started by sports nutritionists such
  as myself. The banana is rich in
  carbohydrate - an important source of
  energy for athletes and has
  significantly higher levels than any
  other fruit. Also, unlike most other
  forms of high-carbohydrate foods, it
  contains very little fat but is also
  high in fibre. The combination of
  fibre with the banana's three natural
  sugars - fructose, sucrose and glucose
  - means it provides a sustained boost to flagging energy levels, thus so
  many players at Wimbledon were seen
  eating bananas.

  Bananas are also an excellent recovery
  food for replacing potassium lost in
  sweating, something most players must
  have been suffering from at this
  year's tournament. - Jane Griffin,
  Consultant Nutritionist to the British
  Olympic Association, London SW17

Sounds like it would be good for long bike rides as well.


What are the physical advantages of riding a single speed with higher chainrings?

The efficiency of chain transmission decreases if one of the cogs has very low tooth count. Track cyclists often use high gear ratios, and large chainrings are used so that a reasonable sized cog can be used. Another reason is that when the cogs are larger, changing to one tooth larger or smaller cog changes gear ratio a smaller amount than with smaller cogs, so larger cogs allow finer tuning of the gear ratio. Both benefits are small, but in racing you use all advantages you can get.

For street singlespeed, the main reason to use large chainwheel is to make the bike look like track bike (isn't this why you bought the Omniums to begin with?). The other popular choice is 42t, because that comes standard with old road cranks and produces nice gear ratio for street use in combination with track cog.


Shimano Nexus 8 speed gear hubs: Difference between SG-C6000-8D and SG-C6001-8D?

Sheldon Brown died in 2008; C6000 came out in 2014, so you won't be getting His wisdom on that site in relation to these.
2014: https://productinfo.shimano.com/download/?path=pdfs/archive/2014-2015_Specifications_v020_en.pdf
gives 6010 (high efficiency) - 8R (roller brake) & 8V (v-brake)
also 6000 (standard efficiency) - 8R, 8V, 8C (coaster-brake)
2015 spec adds -8D (center lock disc) & 8CD (coaster brake with special five-bolt disc)
2016 spec adds 1, i.e. 6010 becomes 6011. And 6010 is deleted.
If one refers to any of the -11 or -01 diagrams, the changes are clear:
https://si.shimano.com/api/publish/storage/pdf/en/ev/SG-C6011-8R-8V/EV-SG-C6011-8R-8V-4040.pdf
https://si.shimano.com/api/publish/storage/pdf/en/ev/SG-C6001-8D/EV-SG-C6001-8D-4131B.pdf
Y3EH98040 vs Y36V98030 Carrier Unit (01)
and
Y3EG98030 vs Y36W98030 (11)
the other change is hub axle unit
Y3EK98020 vs Y37N98020 (01)
Y3EH98050 vs Y37L98030 (11)
i.e. the hub axle unit & carrier unit were both changed because they were deficient in some way
Carrier unit is similar to this

Axle unit is similar to this
http://rideyourbike.com/shimanoaxleunit.shtml
The same parts were also updated on Di2 and Alfine
https://si.shimano.com/api/publish/storage/pdf/en/ev/SG-C6061-8C/EV-SG-C6061-8C-4039.pdf
https://forum.cyclinguk.org/viewtopic.php?t=64432&start=630#p1267269
So basically you can use either hub, but C6001 should be an improved version.


What type of tyre is is the most shock absorbing, between MTB or Hybrid)

The most important thing for shock-absorption in tires is low pressure. The next important thing is width. The wider the tire the more “suspension travel” you’ll have and you can lower the pressure even more without risking a “bottom out” when hitting a pothole or rock.
I think tire type or construction is less important, but generally high-end MTB (or cyclocross/gravel) tires are made to be run at a low pressure. This means a thin and supple construction (especially of the sidewalls) at the cost of being less puncture proof.
So first of all you should lower the pressure as far as possible. When I ride low pressure I usually “test” it by pushing the front wheel hard against a sharp edge (e.g. kerb). If I can make it bottom-out with my full body weight it’s just about right. If you ride carefully you might be able to go even lower, but at very low pressures there is danger of the tire “collapsing” sideways in turns.
Edit: I should add that MTB tires don’t necessarily have big knobby tread. There are also versions with almost no tread or very fine knobs available in case you mostly ride on tarmac or smooth gravel. They should also run smoother and be less noisy.


I finished the ACA southern tier just this last month!

I'd usually be carrying bananas, sardines, peanut butter, oatmeal, knorr rice sides, whole wheat tortillas & granola bars. Less could certainly have been carried, but I'd usually go crazy at the grocery store. Most days you'll pass by a couple reasonably priced groceries so you don't actually need to carry too much on you.

Granola bars are your friends! I started off w/ rice & beans, but they take too much energy to heat up with a stove, and starting a campfire every night is not realistic.

"I will naturally find information for the area I'm in to scavenge for natural sources of sustenance" Don't know how much luck you'll have with that, but you'll be suprised at people's generoristy towards you. There were times when I'd go one or two days without touching my food stores.


Sense this topic has re-opened i will submit an answer.

For custom frame lighting i believe it would be easiest to adapt a product that is already intended for use on bicycle frames or wheels such as what it seen below. It is a weather proof battery box wired to a silicone tube filled with chip LEDs, basically a rope light, the idea is the battery box attached to the hub, and the rope portion is woven through the spoke and centrifugal force with a little help from zip ties keeps it in place.

They come in a variety of colors from a variety of manufacturers. Thus is why i think this would be the most simple and cost effective form to adapt. You could simple attach the battery box beneath the stem or any area out of the way and zip tie the rope where ever you want it on the frame. you could combine colors and get creative with it quite easily.

I know that the US distributor J&B sells them so most bike shops in the US should be able to get them, and ive seen them other places on the net as well. Their rather popular for customizing cruisers.

Heres a couple images of them installed:


What is the second thread on the crank for?

The lock nut is used to wedge to crank on the bottom bracket spindle.
If you open it, you should still not be able to get the crank off, at least not easily.

For square tapered bottom brackets, usually you have to use a tool called a "crank puller", which is hold in place with the outer thread.

See this article over at Sheldon Browns for details and very interesting pictures showing whats going on inside the cranks.


How do you count the number of links in a chain?

Each set of "inner plates" is a link. Each set of "outer plates" is a "link."

In the photo below  you can see two whole links.

Thus to answer the question, Image A in the question above has 4 links. Image B has 8 links.

When you buy this box of chain that is labeled as having "120 links" and is standard 1/2" pitch, you should expect to get 60 inner links, 60 outer links, for a total of 120 links and it should measure 60" long:

Another way of thinking about links is that a "link" as a "place where a tooth goes" - thus if a chain wrapped completely around a 44 tooth chainring - it would have 44 links --  with 22 outer-plate-links and 22 inner-plate-links.

Another way to analogize is with a standard chain:

Everyone would agree that the standard chain image above has six links - each link creating one "hole".

Please note that there is a small but vocal group of people (including Sheldon Brown) who count a "complete link" as "one inner and one outer half-link". Counting "complete" links has the effect of halving the number of links (thus Image A would have 2 complete links, Image B would have 4 complete links, and that five foot length of SRAM chain would have 60 complete links).
Counting "complete" and "half" links as Sheldon does is non-standard at least as far as the industry is concerned. If someone starts talking about "complete" and "half" links when talking about chain length, you should clarify with them what they are talking about as you may end up with half or double the number of links you might otherwise expect.


Raleigh Twenty wheel/rim replacement options

The old stainless steel rims can be a pain to stop in, and when it rains, it's pretty much impossible...I'm a member of The Raleigh Twenty forums, gives good info about the bikes. The technical data for the rims is provided below, but there may be other options aside from what's listed.

According to The Raleigh Twenty Resources:

  Rims:
  Alienation Ankle Biter  20 x 1-1/8" . Lightweight high-performance junior-BMX race rim. Double-walled. Eyeleted. Theoretically available in 28, 32 and 36 hole drillings. I have the 32H version on two bikes. They're very good. Patchy availability.
  Sun Ringle ICI-1  20 x 1-1/8". Similar to above. 28 and 36 hole drillings. Currently available.
  Halo JX-2  20 x 1-1/8". Similar to above. 28 and 32 hole drillings. I'm about to build a set. They look very good. Currently available.
  Crupi Rhythm 20 x 1-1/8". Similar to above but non-eyeleted. Range of anodized colours. 28 hole drilling. Currently available.
  Bombshell and RCR carbon-fibre 20 x 1-1/8". Currently available but WAY TOO EXPENSIVE!!!  And, may not take high pressures.
  Ukai and Araya "old school" BMX race rims  20 x 1-3/8". These regularly turn up as "New Old Stock" on eBay. They were made during the BMX boom of the early 1980s, and are normally 36H only. Being single-walled and non-eyeleted, these are basic rims that are no match for the lighter and stronger modern alloy rims listed above. Patchy availabilty.
  Ukai "mid school" BMX race rimes 20 x 1-1/8". From the 1990s or early 2000s. Occasionally turn up NOS on eBay. These double-walled and eyeleted (sometimes double-eyeleted) Japanese rims are top quality. Rare.
  Unbranded Chinese 451 carbon-fibre rims, direct from the factory online or via eBay. Caveat emptor! Currently available.


There are  Powder-Coating kits that are made for home use. They are available in the U.S. from Sears-Craftsman, The Eastwood Company and others. They range in price from under $200 to as much as you want to spend. The process involves using the supplied gun to apply a colored dry powder to the part. The part is then baked in a household oven. The baking cures the powder to something similar in appearance to a ceramic glaze. It is a very durable finish. It does create some issues though. It cannot be touched up if damaged. The coating is thicker than paint. Threaded holes and close tolerence mating surfaces must be protected during the process. Of course you could only color components that can have all their plastic parts removed.


What parts of a bike could potentially be harmed by degreaser?

Degreaser acts like a solvent (although I'm unsure if it is technically a solvent, or more of an emulsifier).  With all solvents you'll have to be careful with what they contact--however degreaser is relatively safe compared to stronger solvents.

Each type of solvent has its own list of things it will dissolve--and even brand-to-brand can make a difference, so spot-testing is always recommended.

In general though, the risky things are:

Rubbers
Adhesives
Organics (leather, etc)
Porous materials
Paints
(obviously) Grease/lubricants

Your main concerns should be your tires, your paint, and (as you mentioned) components like grip-tape and seats.  Getting degreaser on these has the potential to stain--so extra precautions may be in order.  Typically your best option is to try and prevent it from contacting them, and cleaning it off quickly with mild soap & water if you do make a mess (although soap and water itself will stain things such as leather if you're not careful).

A secondary concern is that you fully remove the solvent after it's done.  Leaving excess solvent/degreaser behind is a very bad idea--see Rubbing Alcohol below for tips.

As for other solvents/degreasers:

Rubbing Alcohol is fairly safe.  It has the risk of drying-out leather and rubber, but is very useful for cleaning parts--and especially useful for rinsing degreaser off of things such as chains (it also evaporates and leaves them dry--ideal for re-lubricating).
Naptha (a.k.a. liquid lighter fluid, not butane) can be very effective as well and is generally safe
Acetone is a stronger solvent, and likely to be less safe.  It should be used with extreme care, but is a very powerful solvent and can get the job done well and quickly.


SRAM X01 Eagle (12speed) in 11speed transmission: it work?

To quote Art's Cyclery:

"Eagle drivetrains are not backwards compatible in any way (the exception being SRAM’s direct mount cranksets, which will still require a new Eagle chainring)"

and VitalMTB:

"SRAM will only make the Eagle chainring in the direct-mount style at first, and we were told it's the only Eagle component compatible with their 1x11 drivetrains. No 11-speed products will work on Eagle."


Inch measurements for wheels are really just labels that often refer to the diameter of the rim plus a nominally sized tire rather than an accurate measurement of the rim diameter.

The 622x19 spec is what you need to pay attention to. 622 is the diameter of the rim bead seat in mm. 19 is the inner width of the rim in mm.

Look at your tires, if they are marked 'ISO 622' or 'ETRTO 622' or '700C' (an French system label that is the same as ETRTO/ISO 622), then they are 622mm diameter.

You can measure the inner rim width of your rims. They don't have to be exactly 19 mm for your current tires to fit. A tire of a given overall width will fit on a range of rim widths.


What features make a disc brake caliper unsuitable for use with other than resin pads

It's not the caliper, it's the disc (it's made out of a soft material). If you put a harder brake pad, it would wear the disc too fast. Actually look at the disc. On my discs it's written: "for resin pads only".


http://wheelsmfg.com/media/catalog/product/cache/1/image/299x299/06866988214b6a9b717ef7211319fd38/d/r/dropout-16.300px.jpg
I think it may be this one (Wheels Manufacturing #16). Is there a broken bolt in the hole just above the rear axle? You will need to find a way to get that out to be able to mount the hanger properly.

For a derailleur, it would be nice to match it with the front, so look for a 9-speed Shimano XT. Try to avoid low-normal (Shimano calls it rapid-rise) derailleurs. Any Shimano 9-speed mountain bike derailleur will work (Deore, LX, XT, XTR). I wouldn't go below the Deore level to keep similar quality level for all components.


The 63-66° and 66-69° exist because there are two types of bicycles.
Mountain bikes have small diameter 559mm wheels and a high bottom bracket for a lot of ground clearance. The combined effect of the small wheel and the required high ground clearance mean the chainstays are nearly horizontal. Thus, the angle between the seat tube and the chainstays is rather high, about 66-69°.
In contrast, road and hybrid bikes have large diameter 622mm wheels and the bottom bracket is typically put as low as possible for making it easy to stop and making the ride feel of the bicycle stable on roads. Thus, the chainstays angle downwards towards the bottom bracket, meaning the angle between the seat tube and the chainstays is low, about 63-66°.
Your Kona Dew is a hybrid bike with 622mm wheels. Most likely you measured correctly: the angle between the seat tube and the chainstays should fall between 63-66°.
Of course you can calculate it based on seat tube angle, bottom bracket drop or height and chainstay length. Your seat tube is at 72.5° angle. Chainstays are 440mm. Bottom bracket height is 280mm. The rear hub height is about 347mm for those 622-37 tires. Thus the rear hub is 67 mm higher than bottom bracket. asin(67/440)*180°/pi = 8.8°.
That should give 72.5° - 8.8° = 63.7° which falls between the angles 63-66°. So there was quite large uncertainty in your measurement indeed.


How to play video games while cycling on trainer?

I can play like this for an hour or so

Get a multi elevation desk (Like this one around $35 from Amazon) it allows you to lower and tilt the TV UP toward you reducing neck strain
adding cheap armrest bars/aerobars (like these around $20 from Amazon) allows you to rest your elbows comfortably while riding the bike, keeping your weight forward.
Adding a heart rate monitor that beeps when you slow down is a good way to remind yourself to speed up.

Tips

Sweat will be a pain with the controller so keep a towel handy.

My Trainer is rather loud, so I use (in the ear) - ear buds. I originally used a cloth - full headset, but the sweat made them stank up.

Doing both tends to create a seesaw effect - Games that require alot of concentration will naturally make you slow down. Going faster (higher heart rate) tends to increase the games difficulty.

As mentioned by @AndyP  below, this will likely decrease performance (at least initially) in both gaming and cycling while doing both, so I wouldn't recommend using this as a method to increase performance in cycling or gaming.

With that said - it is a decent way to burn excess calories and build muscles while performing an otherwise stagnant activity.


Can I get an ebike with a 500 watt motor in Australia?

A 500W motor is not currently legal for use in Australia.

"In Australia the e-bike is defined by the Australian Vehicle Standards as a bicycle that has an auxiliary motor with a maximum power output not exceeding 200 W without consideration for speed limits or pedal sensors.[1] Each state is responsible for deciding how to treat such a vehicle and currently all states agree that such a vehicle does not require licensing or registration. Various groups are lobbying for an increase in this low limit to encourage more widespread use of e-bikes to assist in mobility, health benefits and to reduce congestion, pollution and road danger. Some states have their own rules such as no riding under electric power on bike paths and through built up areas so riders should view the state laws regarding their use. There is no licence and no registration required for e-bike usage.

Since 30 May 2012, Australia has an additional new e-bike category using the European Union model of a pedelec as per the CE EN15194 standard. This means the e-bike can have a motor of 250W of continuous rated power which can only be activated by pedalling (if above 6 km/h) and must cut out over 25 km/h – if so it is classed as a normal bicycle. The state of Victoria is the first to amend their local road rules, see below."

Quoted text from https://en.wikipedia.org/wiki/Electric_bicycle_laws#Australia


Can I use a 700c suspension fork on a 27.5" frame?

Maybe, we need to know more about the new bike.

Wheel size - the 27.5" wheel will probably fit, (provided its not a plus or fat), but if its rim brakes, the brake bosses will be in the wrong place. You may or may not be able to find brakes that fit. If Disc brakes it will be fine

Axle - traditionally axles were all 9mm QR, now there are though axles so you will need to make sure the axle is the same

Headset - standards have changed. Anything earlier than about 2010 will be straight 1 1/8", the tapered steerer became available and more and more popular on MTB's and is moving to others.

Is it worth it - probably not. Hybrids don't typically come with great suspension forks, I would not recommend reusing an old fork unless it was a high quality one and the swap was easy (i.e. headset, axle, brakes compatable). Over time the forks degrade, especially if not serviced, and don't perform as well as they used to. A cheap suspension fork that's degraded is probably worse than no suspension.


What is the relationship between block, gear speed and derailleur? With Pictures

Sheldon Brown to the rescue: http://sheldonbrown.com/gloss_ba-n.html#block

Short for freewheel block; cluster.

My understanding is that the bike has 7 speed shifters and for some reason 8 speed freewheel. Only 7 cogs work, so the seller is planning to switch to 7 speed freewheel. 7 and 8 speed freewheels nearly same distance between cogs, so wrong freewheel can actually work the way described.

One possible problem is that 8 speed is wider than 7, so the frame may have been bent to make room for the wider freewheel and may be bent at the process.


What's the difference between Weldtite Dirtwash citrus de-greaser spray and the WD40 chain de-greaser?

Degreasing chains and other metal components is not unique to bikes. There are way to many degreasing products out there to list. On aircraft, we mostly use varsol, but on my bikes, motorbikes included, I have used dish soap and thoroughly dried the chain then oiled it. Lately I've been washing chains in gas mixed 2 cycle motor oil, hehehe, works good.
Dirtwash Citrus degreaser spray is natural environmentally friendly degreaser that is soluble in water, and reasonably easy to rinse off.
 WD40 chain degreaser is more of a surfactant with petroleum additives. They say it is environmentally friendly, but it contains butoxyethoxy, isopropano, propane, n-butane, and proprietary surfactants.


Chains for fixed gear bike noise problem

At first I thought the chain was rubbing on the wheel, if its a new chain then it might not have been greased. Don't use wd40 if its not greased, it will wear it faster. Try White Lightning.


Discrepancy between old chain length and largest chainring largest cog method

If you are counting links it’s easy to mess up, but it is possible your chain was too long if your rear derailleur had extra capacity to deal with the slack (but not 7 links I think).

Determine chain length using the method in the video below, mark the rivet where you would cut. If you do this properly, making triple sure the chain is on the biggest ring and sprocket, you will not end up with a chain that is too short.

Lay the chains next to each other to compare lengths instead of counting links or rivets.


Will Shimano M6000 Rear Derailleur SG (medium cage) work with cassette other then 42t?

The min/max sprocket size spec of 42 does actually make some sense if you think about how the parallelogram of the derailleur works.

On derailleurs designed for large sprocket ranges the cage is moved a long distance vertically as it moves horizontally. At the inner position, the cage is too low and too far away from the axle to work with a small lowest gear sprocket.

That said, you could probably get away with running 2-4 teeth smaller than the specified minimum. If you want to go to a large sprocket of 30 or less teeth, you should be looking at a different derailleur.


The type of damage shown is often due to under inflation or not centering the valve stem in the hole. When under inflated the tube doesn't exert enough pressure on the tire bead. This allows the tire to spin on the rim. That in turn causes the tube to shift pulling it at an angle and chaffing the valve stem.


Ok, I did it! :-D I took two plates of steel, drilled a little hole in one of them (for the pin), then put the chain between them (pin goes through the hole of course). This served as vice, but because it was not mechanically clamped I could control the force.

Then I used pair of pliers, and without a sweat, pin snapped.

I used the same chain before, but I used regular pin, after a year it came out of the chain (partially), thus this time I used reinforced one. We'll see how good it is...


Does an adapter for a flat mount caliper to post mount fork exist?

From bikehugger.com

  What about fitting flat-mount calipers to post-mount framesets? Think again. No such adapters exist, and if I were you I wouldn’t hold my breath waiting for them to appear. It’s probably not geometrically possible.

Sounds like from that site that it's pretty much not even possible to get it working. Best option might be to sell your old calipers and get some new ones or see if anybody in your area is looking for a trade.


Specifically addressing the second of your suggestions

  split bars with shifter next to the stem

This is a bad idea and would strongly recommend against it.

The GMC Denali uses this method in order to fit grip shifters to a dropbar.

The dropbar has been cut through in the middle, allowing the maker to fit the twist or grip shifters.  These will be generally similar in design to your rotary shifter for a flat bar.  The two parts of the bar have been reattached with a two-part clamshell, which holds the bar-halves with set screws.  However, in order to get the thickness in the clamshell, the maker used thinner bars and left a larger hole in the stem.

The beginner rider might not notice the problems.  Once you start putting a bit of power through the bike, you push the bike down with your hands to raise the pedal and eek out some more power.  To have your bars connected to the bike in this manner is not good, and any failure at any speed will have serious consequences.

Somewhat related example of bar-failure. (ok its a pro whose carbon TT bars failed at speed, not because they were cut in half, but its hard to find relevant video)
https://road.cc/content/news/229200-video-pro-rider-takes-nasty-fall-handlebars-are-snapped-clean

Upshot - don't cut your bars.


Can disc brakes cause front quick-release to loosen?

Most of the time, a bike wheel spins around the axle. When braking, the axle suddenly wants to spin around the point where the brake caliper is grabbing.

The traditional orientation for a fork dropout, with the opening a little forward of straight down, is such that on a rim brake, these forces pull the axle stubs up into the dropout, and no movement can occur.

On a disc QR fork, this orientation of the opening is a poor choice because the axle stubs want to move in that direction under braking forces. Shifting, or in the worst cases ejection, of the hub can occur. A fairly large number of QR disc brake forks have unfortunately been made that use this orientation. That's a trend that's been changing for a while now, but unfortunately slowly. It is the reason a number of QR disc forks have more forward-oriented openings, which looks funny but eliminates the problem.

Skewers that apply higher amounts of clamping force, such as good quality internal-cam ones like Shimano, counteract this tendency but will not necessarily eliminate it.

Usually lawyer lips are sufficient to make actually losing the wheel impossible, but will still tend to allow the hub to shift if the dropout opening gives it a path to do so.


Avoiding being wiped out after work commute?

The simplest advice is: just keep it up. Give your body time to adapt to the new workload you're putting on it, and it will get easier and easier.

For drinks, you can buy gatorade powder and mix it yourself at home. $19.49 for 9 gallons of gatorade is way better than paying retail price for a quart at a time.

As I understand carb loading, it's not something you can do for a repeated effort like a daily commute. The idea is to deprive your body of carbohydrates for a period of time, then binge shortly before an endurance effort. You can't really achieve a level that would be useful inside a repeating 24-hour period.

Lastly, don't sweat protein. It probably wouldn't hurt, but any benefit would be extremely minor for the workloads you're doing, and isn't worth significant effort or attention. Again, just keep up with the cycling and your body will quickly begin to adapt automatically.

Edit: Oh, and one thing that will help is to consume carbohydrates immediately after your commute. The human body absorbs carbs significantly more quickly after a workout, and uses them to replenish any lost stores. Waiting even a half hour greatly diminishes this effect, so the sooner the better. It doesn't have to be a full meal or anything; anything is better than nothing.


Can I use reflective tape instead of a rear reflector in the UK?

Depends completely on the wording of the regulations in the UK, which are the "Road Vehicles Lighting Regulations" or RVLR.

The relevant points of RVLR are:

Lights and reflectors are required on a pedal cycle only between sunset and sunrise.
Lights and reflectors are not required when the cycle is stationary or being pushed along the roadside.
When they are required, the lights and reflectors listed below must be clean and working properly.
Reflectors have to be fixed to the rear of your bike and to the front and rear of each pedal.
The Pedal Cycles Safety Regulations (PCSR) ensure that every new bicycle is sold with several extra reflectors, some of which are not required by RVLR like spoke reflectors (though these are still a good idea)

Rear Reflector
One rear reflector is required, coloured red, marked BS6102/2 (or equivalent), positioned centrally or offside (on the right-hand side of the bike), between 250mm and 900mm from the ground, at or near the rear, aligned towards and visible from behind.
source https://www.cyclinguk.org/lighting-regulations

Full law is at http://www.legislation.gov.uk/uksi/2009/3220/contents/made

Note that the laws are not retroactive, so if your bike predates 1985 then you are not required to update it.  However this is silly and you should be visible at all times.

For me in NZ, there is a requirement stating:

  You must have a rear reflector that is visible from a distance of
  200 metres when light shines on it (eg a car’s headlights).
    source: https://www.nzta.govt.nz/assets/resources/factsheets/01/docs/01-cycles.pdf

No part of that indicates what the reflector should be made of, merely that it points backward and has a certain performance.

Yes that tape would fit the legal performance requirements as described.

But it misses out on the labelling requirement, unless your tape says it conforms to BS6102/2 (or equivalent) To be honest anything's better than nothing!

Note you are required to have pedal reflectors too.  Since clipless pedals tend to not have reflectors, check your cleated shoes which should have some of that tape on their heels too.


Is climbing easier on a light road bike or one with lower minimum gearing?

Lower gearing (or gearing in general) is generally more important than the bike weight for climbing (for most riding as well, sans high level racing). Both of the gear choices are pretty low and you'd need a pretty steep hill (or towing a lot of cargo) in order to need the lower gear over the slightly higher lower gear. As Criggie points out, there are other factors to consider other than weight -- ergonomics, build quality, etc. which can have a more profound effect on how you ride.

A difference of 2.5 pounds is easily within the fluctuation range of your weight over the course of a few days, and is likely on the order of a percent or two of the total bike+rider weight anyway so you can basically ignore it.

As the comments say, you can switch your gearing in the back fairly easily, but this may require a new derailleur depending on capacity and cog size limits and a new chain (this is a relatively easy replacement). Note that you have to give something up for a fixed number of cogs and different gearing combinations (such as the spacing between shifts, max or min gear). So, if the largest cog is 32 in one case and 28 in the other and they have the same smallest cogs, you'll likely have bigger spacings between shifts on the larger cog one. Ideally, you'd try them out and see what you like better.


What Type of Brake Pads Should I Look For?

If you search cantilever brake parts you should find what you need. They are sometimes referred to as threadless  post brake pads.


Why are Avid brakes so difficult to bleed?

It's the design that makes them harder to bleed. Although an 'open' hydraulic system Avid's Taperbore resembles a 'closed' system, one that operates in a vacuum. The Avid system uses a small reservoir fixed amount of fluid in the system and a bladder around the master piston with air in it. Shimano and other brands use a larger reservoir with a bladder separating the brake fluid (in the case of Shimano mineral oil) and air. In both cases air is used to compensate for the fluid in the system expanding.

Because the Avid system operates in a vacuum it requires all air to be removed from the system and that is why you need the two syringe set, other designs simply require fluid to be topped up in the reservoir and air worked out. The Avid elixir system is further complicated by a design that traps air within the taper bore reservoir adding an additional level of difficulty when purging air.

Avids also use DOT 4 or 5.1 which is more difficult to work with than other fluids. Different brake fluids have different characteristics (boiling points, freezing points, amount of expansion etc.). Avid specifies DOT 4 and 5.1, which is a pain. The brake fluid is a solvent so you don't want to get it on your hands but it isn't going to kill you. DOT fluid is hygroscopic, it attracts water so although you can buy it in larger quantities cheaper than through Avid it doesn't have a good shelf life once opened and probably shouldn't be opened again.


The simple answer is, as Sheldon brown says, as tight as possible without binding.
But define binding. The noises you described on your chain in your previous question were symptomatic of binding or of a worn chain. The description you've given there of how you run your chain tension is tighter than I would recommend.

  To clarify the tensioning - When I replaced the chain I adjusted the tension. There was a very noticeable adjustment required. But then when I subsequently adjusted the rear cog I didn't adjust the tug from it's setting with the new chain. I agree that I might have changed the tension marginally just be removing and refitting the wheel.

1 millimeter of movement is too tight, in every case I've seen. The manufacturing tolerances on the components (cog, chain, and chain ring, ans well as the hub, and BB axle), would need absolute perfection to allow that tight of tension to function without damage or noise. I've never seen good enough all at once, and you would need to be amazingly lucky or diligent to find that mix of perfection.

Typical tension on a fixie or single speed is roughly 1/4" to 1/2", or 5-10 millimeters, when pressing on the chain from the top, and from one side. A single speed requires slightly less tension, because the bearings in the freewheel will bind, and it won't roll at all, where a fixie will just be noisy and prone to wear. Make sure you check for the spot where the chain is tightest, and do the adjustment there, as well.

You don't need to be that tight, and your drive train will still maintain good contact between pedal and wheel.


I am willing to switch from 700x23c to 700x28c (front) and 700x25c (rear)

I used a 28mm front and 25mm rear for years on a road bike where the seat stays were too tight for a 28mm on the rear.  I felt that it was the wrong way around (the "fat" tyre should be at the back) but it worked fine.  I never had any issues with control or skidding or the bike feeling unstable.

In my case I used Continental GP4000s in summer and Continental Gatorskin in (Australian) winter, but I used the same model tyre on the front and back - just different sizes.

You'll be fine.


Why would a bike pedal backwards, but not forward?

There is likely something wrong with the rear hub, the bearings may have seized.

If you remove the wheel from the frame can you spin the wheel whilst holding it by the axle?


It's a Mongoose Manuever... late 90's early 2000's if i had to guess. Basically a Walmart or department store bicycle shaped object. There should be a serial number, probably beneath the crank. Pacific Cycles is who bought that division of mongoose which is sold in big box stores.

If you want to know more you could contact Pacific Cycles with the model number and serial number to find out the year, or look them up on google. There are resource sites that help identify the numbers and letters meaning in the model and date codes. Complete guess but i would say a 2002 based on the 02 in the date code.

You have all the information you need to identify it, seems pretty cut and dry.

Bottom line it is not an expensive bicycle, but if it works for you that's what matters.


Frame with a tapered headtube - fork compatibility

The 1-1/8"-1.5" measurement actually refers to the diameter of the fork steerer tube that the bearings will accept, not the headtube of the frame. Your frame therefore expects a fork with a 1-1/8"-1.5" tapered headtube. You can use a straight 1-1/8" steerer fork with an adapter for the lower bearing.

Other geometry considerations are the axle-to-crown length and the rake. It seems that some road forks don't have a axle-to-crown length specified but are generally the correct length for a ISO 622mm wheel. Small differences in length will not make a difference to steering geometry.

If you are looking for an MTB suspension fork, you need to consider wheel size and travel. I think there are a couple of dropout spacings used in the MTB world as well.


Youth bike sizing is traditionally done by the wheel size. Check your tires they may say 16".

Other possibility is the 16" is top tube length (from center of seat post to center of headset traditional measurement)


Suggestions for buying a bike for commuting

Check out:

For a long (25mile each way) commute, what kind of bike should I look at?

What bike+equipment for a long daily urban commute?

How do I change a road bike into a commuter bike?

Relative efficiency of different commute bike setups

Equipping a commuter bike

What is the narrowest tire you would use for commuting?

(And others)


As mentioned in the other answers, there could be several reasons that your rear tire is always muddier than the front after a wet commute.

The front tire splashes mud on the rear of the bike.
There is more weight on the rear tire, causing it to sink deeper into mud.
Your power is being transferred to the rear tire, creating more friction than on the front.
You're probably using your rear brakes, causing your rear tire to slide.  If so, it's probably better to use more of the front brake.

One more thing... the mudguards are probably not keeping your wheels and tires clean.  They're there to keep you from getting splashed.


Your tire size is 700x38, meaning the overall width of the tire is 38 mm. Inner tubes are sold in ranges of sizes rather than for specific widths.

eg 700x23-25 - means this is suitable for 23 to 25 mm;
700x28-32 - suitable for 28 to 32 mm;
700x35-42 - suitable for 35 to 42 mm;
and so on.
So you need to find a tube has your tire width (38 mm) that falls within the range that's on the packaging of the tube you're looking at. And make sure that it is with a Presta valve rather than Schrader.

Edit: just to be clear, the above ranges are just examples. Different manufacturers may have slightly different ranges.


My immediate thought was that you have ISO/ETRTO 630 rims (what used to be known as '27 inch' on older road bikes) which are of course a bit bigger than but sometimes confused with 622 '700c' rims. According to the CR18 page on the Sun Ringle site those rims only come in 622 and smaller. Perhaps 27" versions of these rims were made in the past so you should confirm what size you rims are. 630 and 622 are the bead diameters in mm so it's easy to check by measurement.

if you so have 622 rims, so what you probably have is a slightly oversize rim and slightly undersize tire. Some tires are known to be undersize and hard to get on.

You may just need more force to get the tire on. Make sure the bead is sitting in the deepest part of the rim 'valley' as you try to get the last part over the edge.


Eagle chain B-gap adjustment without plastic tool

This measurement is given by both Shimano and SRAM as the shortest distance between the circles formed by the tips of the teeth of the largest cog and those of the guide pulley.

The spec for Eagle is 15mm.

A simple way of actually doing it is to hold up a 15mm wrench, caliper, track nut, etc to it.

Give it a little fine tuning once the chain is on and you're setting up the shifting. You'll be able to tell how small changes (1/4 turn-ish) have some bearing on how smoothly and quietly it all works.


How to roll-start with a back-pedal coaster brake?

There's only one solution I can think of, but it's a sweet one.


How do I determine if my front wheel is warped?

Lift the bike up and spin the wheel while you watch it closely, at the top of the fork.

The tire should remain centered between the two sides of the fork as it spins, and the surface of the tire should not move closer to nor further away from the top of the fork.

If you have rim brakes, the rim should remain in exactly the same place relative to the pads as it spins.

In cycling vernacular, you need to check if your wheel is true.

This video covers the entire wheel truing process:


Both. It's a bit like asking whether you should fix the brakes or balding tires on a car - you need to fix both to be safe on the road.

But you don't need to shell out a huge amount of money. See if there isn't a bike coop or community repair station in your neighborhood:

Truing your wheels requires some elbow grease but shouldn't require any parts (unless your spokes are broken). In terms of tools, at minimum you need a spoke wrench ($5) and ideally a truing stand, but you can do a fair job truing against your brake pads. The coop will definitely have spoke wrenches and may have a truing stand.
Repairing your brakes at most would require new pads ($5-10) and maybe new brake cables ($10-15). Replacing brakes and cables requires just an assortment of small hex wrenches and allen wrenches, which the coop will have.

The true cost is in the labor and if you can do it yourself with youtube and human help, you should be able to get it in at least running conditions. For the wheel truing, I'd try to go for just "good enough" and not perfect -- and try to get someone to supervise you -- as it's easy to mess up truing if you go too far.

If you don't have a coop in your location, the spoke wrench, Allen wrench, and small hex wrench should all cost less than $25 total for cheap ones or for a multi tool that has them all. The real value of the coop is someone looking over your shoulder to help, especially with the wheel truing.

Given that an accident on your way to work  will cost you lost wages, maybe losing your job, and perhaps a hefty hospital bill, spending $25 for a self-tune or around $100 for a bike shop to do it is money well spent.


Can I reorient my dérailleur so the top jockey doesn't hit the cassette?

On these Shadow derailleurs, there is a tab that must rest on the bottom lip of the derailleur hangar.  (I'll note at this point that you must use the correct hangar for your bike. "Almost" like it or "derailleur has the same angle" when an incorrect hangar is used doesn't cut it. Millimeter differences create big changes in the workings of these things.  Consider how a few rotations of a fine threaded Barrell adjuster can change a whole gear.  Or if the cable is not routed just right--like say misses a small little leverage tab, the derailleur won't be able to get onto certain gears.).  If the little tab isn't touching the lip of the hangar, shifting will be compromised.  In addition, I see your derailleur's cable is not properly seated into the derailleur's housing.  That will eventually cause excess friction and poor shifting.  While one doesnt necessarily need  ferrule at this point on the external  (the derailleurs cable seat/stop can act as one)—a sealed ferrule will prevent easy contamination of the inner cable at this vulnerable spot.  Full Suspension bikes utilize the aluminum ferrule to help prevent ghost shifting when the suspension moves.

Note the things I'm talking about on these pics of my XT Shadow der.   My cassette is an 11-36. Up front I have a 2x crankset, 38-28, and I'm on the big ring.  You have to hold the derailleur just so on install so that tab gets seated in the proper spot. In this Dealer's Manual from Shimano these issues are discussed.

Finally. When a rear derailleur and it's cable are installed correctly, manipulating the B-screw moves the upper jockey wheel closer to or away from the cassette. Clockwise rotation moves the screw in and the jockey wheel away from the cassette; anti-clockwise moves the jockey wheel closer to the cassette. See photo for location and a view of the proper distance the jockey wheel should ride from the cassette.


The valve isn't the limiting factor for the pressure -- you can go well above 80 psi with a Schrader valve.

If you're holding 50 PSI in the tire (the tire should feel a bit firm, but you can likely push it in a bit with your fingers), you shouldn't be leaking. I'd try depressing the core (pin in the center of the valve) a bit with a key/small screwdriver/finger nail to make sure its free and try pumping it up again.

If you're not holding the air in the tire, you either have a bad valve or a leak in the tube (in which case, get a new valve core/tube in the former case, and patch/get a new tube in the latter case and check the tire for damage).

Failing that, I'd try a different pump -- not all pumps are able to reach high enough pressures, but 50 psi is on the low end for the limit of a bicycle pump not specifically intended for low pressure situations like fat bikes (then again, a pump designed to do sports balls only needs to pump about 8-10 psi, so its possible). I'd try a floor pump like this one.


It's almost certainly cork that is used in the bar tape for its vibration damping and sweat absorbing properties.

It's clearly visible in this promotional image for Cinelli tape:


Adding to the first part of mattnz's comment

  You should check they are working and adjusted properly by applying them a few times at the start of each ride, this should be enough to stop them sticking from lack of use.

That, of course, applies to both brakes.

I would recommend using your rear brake more, since it's adequate for most braking tasks. I generally use both brakes in most situations. This gives me a good feel for how each is working, so when I really need them I have a good idea for what will happen. In emergency situations, though, remember that your front brake is 50% more powerful than the rear brake.

Another reason for ambidextrous braking is so that you can signal with either hand while braking. It has to be said that for most people this is a higher level skill, but you can begin to do it by braking gently.

But for completeness, I should mention that some people say the rear brake is almost useless. You can form your own opinion after reading what Sheldon Brown says here.


Why did the bike shop put grease on my seatpost?

On old steel bikes a good reason would be to prevent the seatpost from rusting onto the frame, thus preventing saddle height adjustment.

More recently I understand from my LBS that you do it to prevent water from seeping into the frame along the (imperfectly sealed) seatpost. Depending on your frame you could end up carrying one or more kilo's of water with you if you have a lot of rainy rides.


What should I check with set up of a tandem?

In addition to the pre-ride checks covered here, I suggest you check that:-

The sync (timing) chain between the front and back pedals is not too slack. You can expect it to move a centimetre or two closer when pinched, but visible droop is bad news and might be causing feelings of sudden changes of cadence.
The pedals are in phase. That is, the right pedal on the front is at the top when the right pedal on the rear is also at the top. Some tandem teams prefer to be out of phase, but in phase is standard and easiest for a beginner. I would expect all hired tandems to be in-phase.
The tires are suitable. As tandem tires carry more weight, it is worth having wider, tougher tires. On a road tandem I would say 28mm is a minimum. My wife and I use Schwalbe Marathon Plus 35mm (1.35") and we aren't heavy.
The tires are at high enough pressure. As above, the right pressure depends on tire width and rider weight, so is generally higher for a tandem.
There is no keel tube/chainring damage. The bottom horizontal tube between the two bottom brackets can sometimes hit the ground if ridden over bumpy surfaces due to the long wheelbase of a tandem.


I'd use a 14 mm socket to undo the nut/bolt.  Then you need a crank puller tool to lever the crank off the bottom bracket axle.

Daniel's point is correct - are you positive its the crank/arm to axle that is loose?  Its more common to have misadjusted bearing cup/cones in the bottom bracket, and the whole pedal-structure wobbles.


Muscles sore and ridicously stiff after riding

Have think about your bike fit, I once had horrendous ITB pain from setting my seatpost just a few mm too high. There's plenty of conflicting advice and opinions you can research.

As well, are you doing any pre/post ride stretching or body care? I use a foam roller on my legs, just a few minutes in the morning and evening (I commute to work & back) does wonders.

Finally, rest days are important! If you're going every day from a history of not riding, kick back and let your body repair itself.


Ackermann compensation for tadpole trikes- how to work Peter Eland's spreadsheets

The story about pointing to the center of the rear axle is valid but sometimes you have to set the ackermann a bit of in the positive or negative direction. In my setup the full ackermann works fine.

You might be able to solve your problem by making an animation of the setup so you can see the angle that the wheels are making when you turn the handlebar. I tried but I did not succeed in it.


Relation formula between fork length change to headtube angle and bottom bracket height

This isn't a formula for you so maybe not the answer you're looking for, but it gets tricky because a fork isn't just a straight line; because it has offset it's kind of like a triangle itself for the purpose of doing the exact math here.

The thing most people who care about this question would do in practice is model the frame's fixed points in a 2d CAD program, model the forks in question (remembering that to do so you're making a right triangle where the axle to crown dimension is the hypotenuse, the offset dimension is one leg, and the other leg is an unknown length that can be solved for or figured out automatically in CAD), then plug each fork in to the frame model such that the unknown leg is in line with the head tube, and then pivot the whole thing around the point of the rear axle until the front axle snaps to being in plane with the rear. Then you can see the resultant head angles and BB heights easily. You can also easily see what angle changes at the headset would give you. There are many free 2d CAD programs that can do all this.


Do older Dawes cycles use standard components?

I'm not sure about old Galaxies, but in the case of the Streetwise, possibly not. I once restored an old Dawes and found it a bit of a nightmare - for a start the seat tube was an odd diameter which made fitting the front mech interesting. The seatpost was 26.8mm which is not unheard of but does limit your options. The headset was the old JIS type (Japanese Industrial Standard, I think) which had slightly different diameters (head tube 30mm, crown race 27mm) to a standard 1" threaded (30.2/27.4). And finally the rear mech was fixed on with a strange bolt-through arrangement which meant that the threads for the mech hangar had never been used, and needed tapping as they were covered in paint.

So basically don't count on it :)


Shifter cable cut deep groove into the rear derailleur casing

I was able to rotate the grooved tube 180 degrees with a flat screwdriver wedged into the groove. I cleaned the area and applied a bit of Crazy Glue around the tube. The shifter cable is now in contact with the unworn part of this tube and excessive friction in the system is gone.


Why do cyclists prefer messenger bags over backpacks?

I spent the last two years as a backcountry ranger, in Northern California.  There, I wore a backpack almost every day.  Now I am a bicycle commuter in Sacramento and I choose panniers first, a messenger bag second, and the backpack a distant third.

There are three reasons why the backpack is my last choice in this list.

Any bag I carry ends up being full.  I don't know how that works, but my bag is always full of something.  A full backpack rides higher on my back than a messenger bag.  This raises my center of gravity and throws me off balance more easily.
It doesn't matter how gently I ride or what the temperature is, by the time I get to work I am soaked with sweat.  With a backpack, I sweat even more because there is less airflow between my back and the bag.  The messenger bag, which rides lower, covers less of my back and I sweat a little less.  Or maybe I just dry out quicker.
Backpacks with hipbelts and sternum straps are designed to move weight off of one's shoulders and onto the hips and torso.  This works great if you are in an upright, walking position.  When I'm in the drops on my roadbike, a hipbelt is nothing more than a hinderance and a backpack-sternum-strap, though more useful, sometimes tends to choke me.  Weight is again transferred to my shoulders and back, which causes me some degree of pain after a while.  Messenger bags--at least those that are well designed--have a strap which rides diagonnally across the sternum and which functions better in the riding position to transfer weight to the torso.

Panniers are my first choice, though, because they better solve all of these problems.  They are completely off of my back and pretty low on the bike.  For longer rides and for my daily commute, I generally use panniers.

Not all of my bikes have a rack, though.  I have ridden my bike from Sacramento-to-the Bay Area wearing a messenger bag.  I wouldn't have tried it with a backpack.


Are my cycling shoes too big? With 3/4 inch of room

1.9cm (3/4 inch) is a lot of room. I assume you looked at the imprint of your feet on the insole.
I have about 1cm room in my Specialized Expert shoes and I regret not getting them at least half a size smaller.
Things which annoy me about my too-large shoes:

Walking can be awkward because my feet float a bit and especially ankle stability is just not there because the foot can twist inside the shoe. I’m also more likely to trip over the tip of the shoes.
The shoe’s tongue goes too far up and starts biting into my feet after some time. Fortunately it’s possible to push it further down.
It’s easier to hit the front wheel in sharp turns.

Riding itself is fine since they more or less just have to provide a secure platform for your feet. I can also move the cleat far enough backwards.
There is a slight advantage in cold weather because you can easily wear two pairs of socks or waterproof socks.


That's an adjustable height stem. Looks like it has some sort of quick release and adjustment.

If it is irreparably loose it's a safety issue. The joint could collapse and the handlebar would drop down and forward suddenly.

Either: pass on this bike, or negotiate a lower price with the seller and plan to replace the stem. You'll need a riser stem for a threaded steerer tube. These are not too costly and easy to install with common tools, usually just a couple of sizes of hex wrench.

BTW, the brake lever angle looks wrong, seems to be angled down too far. Levers should be in line with your arms when sitting on the bike.


Absoluteblack oval chainring doesn't completely fit GRX crankset

For future reference, these particular chainrings will fit just about any Shimano 4 bolt EXCEPT the GRX. They mount a bit strange compared to many chainrings as you can see in this image, the bolt comes through the crankset from behind and screws into the chainring.

Compatibility
Shimano Dura-Ace 9100, R9120, R9150 & R9170 Di2, Ultegra 8000, R8020, R8050 & 8070 Di2., >105 R7000, R7020, R7070, Dura-Ace 9000, Ultegra 6800, Shimano 105 5800, Tiagra 4700 ; 10 >/ 11 / 12spd compatible. In short ALL Shimano 4 bolt cranks except GRX.
Chainring has 1.5mm offset towards frame for perfect chainline.

Source: Absolute Black


Could someone please identify this bike and tell me the cost/price?

It's a Schwinn Frontier circa late 90s. You can read the branding on the tubes and the 90s part comes from the rigid fork and similar matches in Google image search.

  I googled everywhere online but I can't find this exact bike and I'd also like to know the price.

The price evaluation is discouraged on Bicycles SE, but knowing the model you can look for ads and see what other people sell/buy it for.


Front disc brake wobbling / grinding on pads after full braking and minor plunge

Two possibilities - the wheel itself have shifted, unlikely with a though axle though.  The crash does not seem to have be bad enough for a major damage like deformed hub to damaged carbon fork (Carbon is far tougher than many people make out and tends to fail catastrophically). However, if you have concerns over the fork,  get it checked by a bike shop.  While the risk of damage might be slim, the consequences if the fork fails are about as bad as it gets.

Its likely that the caliper has taken a knock and shifted on its mounts. All that will be required if this is the case is aligning the caliper.  Refer Park tools website for detailed instructions  https://www.parktool.com/blog/repair-help/hydraulic-disc-brake-alignment

The short version is to loosen the caliper bolts, apply the brakes gently hile spinning the shell, as you tighten the bolts slowly and carefully. This will center the caliper and and alight the pads with the disk.


Getting back on the bike after bad fall, how do I get over my fear?

Up front, I must say I'm not a mountain biker.

But I have had some big road crashes, and done a fair bit of off-piste downhill skiing. I understand the fear you describe. Let's analyze what you've told us. Understanding the cause and learning is the key to going beyond. Like when I broke a leg ski racing - I got over-confident and over-rotated into the tightest steepest gate, caught the outside edge, and with a sound like a gun-shot my tibia exploded. The point is - I learned the cause, and learned to ski better.

You say "a stupid bad crash ... my wheel got locked". Translation: "I was riding beyond my skill (and maybe equipment) level and got found out".

How to get back? Firstly, learn from it. What skills did you need right then that you could not call up right when you needed them? I already said I'm not a MTBer, but I have a few suggestions

Concentration - did you loose concentration at just the wrong time? One skill to learn is "switch on". Approaching a tight bend - switch on! Approaching a steep descent - switch on! You get the idea - switch to full alertness and concentration.
Steep downhill - revise all you've learned about the basics of downhill, and practice starting back with really gentle, safe descents. Relearn those skills, doing it again and again. Gradually working up to steeper and steeper hills, with a variety of trails and surfaces.
Reframe - you say you're terrified. Think of it as respect. You've learned a whole new respect for steep hills, and rocks.
Be positive - you only broke a few teeth. It could have been worse. Perhaps you'll wear a full helmet next time you go someplace like that.
Your road skills have nothing to with the crash. It's great that you're riding at all, but you crashed doing downhill; they are the skills you need to revise.

Don't expect or force yourself to ride beyond your skills and new found level of respect. And don't let anyone pressure you either. The key is confidence. Not over confidence. Without confidence, like me skiing a steep slope, you are certain to crash. But with well-founded confidence in our skills we can do much better.


Are any anti-theft GPS trackers dynamo powered?

I use this product:
http://www.aliexpress.com/item/Spybike-Bike-GPS-Tracker-to-spy-and-pretect-your-bike-with-ease-New-bike-tail-light/32251529357.html
Since this is a tail light, it is less suspicious as a GPS tracker. You can simply charge and remove the USB cable as well.
(One thing to notice since this product is not inexpensive, I epoxied the screw just to be on the safe side :D )

For anyone without a USB 5V DC port from your dynamo hub:

http://www.ebay.co.uk/itm/BICYCLE-DYNAMO-USB-REGULATOR-PDA-PHONE-USB-CHARGER-M172-/370935357198?pt=LH_DefaultDomain_3&hash=item565d785f0e

Tigra Sport Bike Charge Power Conterter

or.. just search google for "Hub dynamo USB" if you are not from the UK :D

and for anyone who loves DIY to make your own AC-DC regulator:
https://parttimetinkerer.wordpress.com/2011/11/12/charging-usb-devices-from-a-hub-dynamo/


What are the side effects of blood doping?

Basically, the intended effect is to increase the number of red blood cells in your system, which in turn gives you increased oxygen carrying capacity to the working muscles. This extra oxygen allows your muscles to work longer and harder.

In the early days of "blood packing", circa the 70's and 80's, it was basically taking a couple of pints of blood out of the body, storing it and letting the body naturally replace it, then transfusing it back into the athlete before their events.

Erythropoietin has actually been around since the early 1900's, and in the 60's, they found that it stimulated blood marrow to produce extra red blood cells. In the late 80's, a synthetic EPO agent was created, and this is what led to the EPO use as an athletic enhancing agent, other than its legitimate medical uses (Anemia, and other diseases).

The biggest effect from extra blood cells (Other than the risk factors of homologous blood {Blood from an outside donor}) is that the blood becomes thicker and more viscous. This can lead to blood clots, strokes, heart attacks and pulmonary embolism. This becomes more likely at rest/sleep, as the heart rate slows quite a bit.


How to judge comfort when buying a new saddle

This article, The Four and a Half Rules of Road Saddles, from Cervélo Cycles has been really helpful to me when pondering saddles. I think the key points are:

The saddle needs to be wide enough to support your "sit bones" but not so wide that it chafes on your thighs.
The saddle has to be flat enough that the part between your sit bones doesn't press up on your soft tissues.
If the saddle is padded, make sure the padding doesn't defeat the flatness.
A cutout might help.

Also make sure that you've got the saddle adjusted well. Make sure the height is high enough, but not too high (I start too high and work down, because it seems easier to recognize too high than too low). Also make sure that the saddle is level – nose up can make the pressure worse, nose down and you may feel like you're slipping off the front to the saddle.


Several solutions:

Clear cycling glasses (which you've tried)
A helmet with a windscreen / windshield / visor that'll help keep the wind and the light from streetlamps and cars out of your eyes
Saline or "liquid tears" eyedrops (helps with dry eyes, in the "Eye Care" section of your pharmacy)
Liquid tears with a vasoconstrictor (helps hide the appearance of red eyes, e.g. Visine)
Liquid tears with antihistamine (helps with allergies, e.g. Visine-A)
An oral anti-histamine (assuming it's because of allergies)

I have no connection with companies selling liquid tears. I should note that many optometrists recommend against regular application of anything except pure saline drops because your eyes become habituated to the chemicals (especially vasoconstrictors) and this can make the situation worse.


2 broken spokes same side, can I replace with one from the other side?

Can you? Sure!
Should you? Well...
You say it's a mountain bike - what kind of riding do you do? If you're mostly doing commuting on smooth roads, you should be able to get away with it through careful riding, avoiding curbs, pot-holes and other harsh knocks. If you're riding off-road on even moderately bumpy terrain, I'd say that's a prescription for a wheel failure which will end up in another accident, and this time it may not be just the wheel that ends up broken.
As far as spoke wrenches go, when I last really worked on a wheel, the top of the nipple had a small slot in it where you could use a slotted screwdriver. It appears that they still do:
Shamelessly stolen from Bike Parts Place.com
You can remove the tire, tube and rim tape then use your screwdriver in this slot. I'd suggest that when you order your spokes you would want to order either a multi-size spoke wrench or a set of single-size wrenches (I just picked up a Parke Tools multi-size one last night for $10, the set was about $15) as that will make quick tweaks to truing much easier in the future. I'd also suggest ordering a few extra spokes, just to have them on hand should this ever happen to you again.
Since it's your rear wheel and that takes the majority of your weight, I'd suggest that you'd want to temporarily replace both of them with spokes from the front. Where from the front you'd want to pull them, I'm not certain - I'd hope someone else will chime in on that. Pulling them from right next to each other increases the weakness at that spot, but makes it easier to maintain true, while pulling from 180° from each other spreads the weakness, but makes it more difficult to true up.
As a side note, I'm curious where you are that you've got a bike with 29" wheels - I certainly don't know all there is to know about bikes, but that's a diameter I've not heard of before.


You are fine and your understanding is correct. It's the total stack height of the spacers and the stem between the top of the headset and the cap that matters, so spacers can be swapped from below the stem to above and vice versa to adjust your stem height as you like it.


Magura Vyron dropper seatpost internal shaft can be easily twisted

Something similar happened to me a couple of years ago, after my bicycle was transported by a freight company for several thousands of kilometers, and the Vyron seatpost apparently had received a couple of sideways strikes.

You do not provide details about which seatpost's parts are loose. I'd guess it is the internal movable shaft that now rotates against the external piece. It seems (at least it was so in my case) that the shaft of the seatpost is threaded into something inside. It means you can thread it back to be tight by rotating the shaft clockwise (looking from the top). Be careful to not unscrew it all the way out of course, it should get tighter quite soon after you start rotating it.


What is the total equipment weight of a tour rider?

Weighing some of my own gear, and allowing some reduction because I'm not especially up to date ...

Helmet 350g to 400g
Shoes 300g to 350g
Outfit 350g to 400g, 100 to 200g more on a cold or wet day.
Misc 150g (sunnies, comms gear, etc)

Total... 1.15kg to 1.3kg, plus .1 or .2kg depending on conditions.