Building a wheel with a Dyno Hub
 

Bought a new Trek 520, and want to add a Schmidt Dyno Hub with a Luxos U headlight and the appropriate tailight. The front wheel that came with the bike is a Bontrager Camino. Am I being silly to have the wheel taken apart and reassmebled with the dyno, or should I just build up a new wheel from scratch? I would prefer since its a brand new bike to have the wheels match. What questions should I be asking the LBS about building/rebuilding the wheel? Is building a wheel "rocket science" or something that a vetern bike mechanic can handle with ease? Thanks for the input

Either way is fine, though I hate taking good wheels apart for any reason.

If you're considering taking the wheel apart, run a set of spoke length calculations, for the existing and Schmidt hubs, to see if you can reuse the spokes. The difference won't be great and reusability will likely depend on how much working room is left in the nipples. Ie. if the spokes already reach the tops of the nipples, and the new build calls for spokes 3mm shorter, you're SOL, but if the spokes are on the short side now, you might be lucky.

Whether you need new spokes or not will factor into the economics of your decision.

As to wanting matching rims, I understand that, but realistically front wheels tend to outlast rears by quite a bit, and most experienced cyclists have a slew of used but good front wheels. You might consider buying a pair of rims, and having them match if/when you need to rebuild the rear.

If you can get a matching rim elsewhere that may be silly - keep that wheel as a spare and build another. The spokes may not be reusable due to length or builder policy (I wouldn't bet my reputation on the original spoke quality and fatigue they experienced) and much of the value is in the labor which goes into a wheel. Otherwise it makes sense - once you get past budget, basic functionality (clearance for panniers/tires), fit/contact points, and gearing bikes are mostly about satisfying your sense of aesthetics.

Nothing. There's a significant chance they'll do a bad job which produces a wheel that folds up on a small bump (I quit letting other people build wheels for me after that happened) or never stays true (the rear wheel in that set never stayed true due to low tension, and when feeling lazy I let a LBS swap a 3 speed IGH for an 8 on my wife's bike. I literally spent more time correcting that mess than if I'd started from scratch).

Find a reputable one-man wheel building operation (Peter White and pcad would be the first two that come to mind) and have him do the job. A shop known for good wheels is not enough, since the new guy can make your wheel before he gets fired for incompetence. A shop known for having good mechanics is not enough.

Or read Jobst's book and build the wheel yourself. It's time consuming but not difficult. Some of us enjoy the process in a meditative sort of way, especially with beer. I never had to true the first wheel I built for 13 years at which point I'd broken my leg, grown past 200 pounds, and learned that 400g rims which work great at a 145 pound racing weight are easy to bend with that sort of load.

No. Jobst Brandt tested his book _The Bicycled Wheel_ by having each of his grade school sons build a pair with no additional help.

Mechanically I find wheel building about as difficult as adjusting a clamp-on front derailleur. This isn't enough to imply a good mechanic will build a decent wheel - it takes much longer which interferes with his profit generation.

Bike shops make more money by having their mechanics work on fast high-priced repairs and upgrades like fixing flat tires and installing new cables than building wheels so the mechanics are under a lot of time pressure. I speculate this causes them to do a bad job (I find the other alternatives of professional mechanics who are illiterate or less mechanically adept than grade school boys less plausible).

At the low end most people are best served by something out of the Quality Bike Parts catalog; like the guy with a 1980s bike boom 10 speed who gets a $25 wheel. Farther up the food chain people want boutique wheels that look flashy and the shops make more profit on such wheels than hand builds. Consequently mechanics don't get enough practice building wheels right so they're fast enough to build good wheels within the time they're allowed.

Somewhat off-topic here, but why do you say that front wheels outlast rear wheels? The front wheel takes most of the braking force, so I'd think the front rim would be the one to wear down fastest from the braking force.

Thats what I did, re spoked the Dyno-hub in the same rim, ..


for the above post, some.. people wear through rear rims first because of dragging the brake shoes longer , behavior , scrubbing speed a bit,

than using sharp quick stops with the Front and the rear.

+ the greater % of weight and acceleration ..

alternatively build a whole new wheel , the matching rim will come in use, later,

when you need to replace the rear rim as then you can tape it alongside the other one
and just move spokes over .. without disturbing the lacing pattern..

Because they do, and by quite a lot. Ask anyone who puts high miles on their bike(s). My best example is a pair wheels built on 32H Mavic Open 4CD rims laced 3X that were installed at the same time on the same bike. The rear cracked through the brake track a just over 11,000 miles. The front lasted 33,000 miles. The same goes for front tires which outlast rear tires by at least 3 to 1.

That's correct but the front wheel runs in a much cleaner environment. The rear rim gets sprayed by all of the grit and dirt thrown up by the front wheel so it is subject to much more abrasive wear. Also, front wheels carry much less of the bike/rider weight and are more likely to be steered around holes and obstructions in the road the that rear wheel goes right over so they survive impact damage a lot longer too.

That may be true, but rears take more of a pounding, and because of the tension differential don't hold up as long. Spoke breakage in front wheels is almost unheard of, except for low spoke count wheels, and in crashes, whereas spoke breakage, and rim dents from potholes kills off rears sooner than brake track wear.

The fact is that there are plenty of fronts out there collecting dust, but the same people tend to have fewer rears.

OP; If you can stand a suggestion that is very easy to implement is cheap...and you are not running disk brakes or a drum brake on the rear wheel. Recommend jump on ebay and buy a SunUp Dyno kit for $125 delivered. I originally chased them down due to the high cost of a 48-spoke dyno hub (only the SON Classic is available at nearly $300) for the front wheel which generally leads to a $400 wheel. I didn't like the sound of that. Turns out the SunUp unit is just about what its sellers claim for it; Puts out a bit more power than a normal dyno hub and is a good bit more efficient. It is built like a tank and very quiet too. If you are using 48 spokes at 3 cross or less spokes it installs in a flash and can be moved to a new wheel in 10 minutes or less should you have to replace a wheel. If you are wanting to charge up phones and e-toys, then suggest also buy their little do-dad box which is normally listed down at the bottom of the ebay page. On the other hand, if running 48 spoke 4 cross, the standard widgets that go between the spokes to mount it don't really line up at all, so just recycle the mounting bits and use about 4 or 5 nylon wire ties instead and nip the extra length off (if touring, put a couple of extra ties in your kit just in case). I was skeptical at first but now routinely recommend the SunUp unit over other dynos if one doesn't already have a quality wheel built up with a classic dyno in it (yes a SON or similar is more cool of course).

Hope that helps
/K

I'll check it out, thanks for the info