WheelEvaluation

This is an advanced job that requires a lot of knowledge about wheels and wheel repair. However, this makes it a great opportunity for someone who doesn't have this knowledge to learn by working with someone who does. If you are going to be evaluating wheels by yourself, you should be familiar with all of these aspects of wheel repair:

  • Flat spots or other impact damage and how to find them
  • How to spot a bead hook on a rim
  • How to quickly tell how out of true a wheel is, and see hops
  • How corroded is too corroded for spokes
  • Finding rounded and/or frozen nipples
  • Telling the difference between wheel sizes on wheels without tires attached
  • A basic knowledge of wheel sizes and what they're used for

Having these skills also implies a knowledge of basic truing. Although this process doesn't require much actual truing, it would be difficult to have a good eye for how out of true a wheel is without having trued before. There are steps of the process that anyone can do, so even if you don't have all of these skills, read on.

Basic Categories

The main goal of wheel sorting is to determine whether a wheel should be despoked, repaired, or just put out in the backyard. Despoke wheels typically have one or more good parts, but a fatal flaw as a wheel. A good example would be a wheel with good spokes and a good hub, but a rim that was ruined in a collision with a pothole. Wheels to be repaired are the ones with no fatal flaws. Backyard wheels are ones that are either a complete loss, such as a wheel where the rim, spokes, and hub are all ruined, or cheap steel wheels which aren't in great shape but could be used as is, since the standards for steel wheels are fairly low. These wheels are free for members to take, if they need them; an individual who needs a wheel and can't find anything better may find it worthwhile to repair them although the co-op does not.

Wheel size

The first step of the process is to determine what size the wheel is. You will probably do this either by looking at visual cues or by the obvious size of the wheel, but sometimes if the wheel could be, for example, 700c or 27", you may need to check with a tire. The reason you need to check is because some wheel sizes are much more in demand than others. Here are some guidelines:

  • 622 - 700C, rarely 28" or 29". 700C wheels are not particularly in demand, since 700C bikes are relatively rare at the co-op. They only appear on relatively modern road bikes and large-wheeled "comfort" bikes, which we see few of. However, the supply is even smaller than the demand, and most of these wheels were pretty nice to begin with. These are a good size to start the list with, because you should essentially just make a "fair" evaluation of 700s - you don't need to be overly generous or demanding. A decent amount of rim damage to one of these wheels will usually mean that it will never ride as nicely as it should, but it might still work well enough to be a decent wheel. If you think a flat spot can be fixed well enough for safe braking, save it. All of these wheels will be aluminum and have bead hooks - if you find one that isn't, it is probably not worth saving. If spokes are corroded, up to 2 or 3 rounded/frozen nipples should be ok, at which point the wheel becomes a despoke unless the rim and hub are also completely ruined. It is very unlikely that a 700C wheel will end up in the backyard - they will almost always be repairable or have a useable part - even if it is just the aluminum rim, useable for non-bike fabrication.
  • 630 - 27" wheels are always in demand, both front and rear. We need aluminum more than steel, of course, but we actually have trouble keeping up with the demand for steel. We need a lot of these because bike boom bikes had skinny tires and many riders succeeded in denting their rims. Because of this, your standards will be fairly low. Any aluminum 27" wheel without a decently damaged rim will be considered repairable. Steels that aren't more than a few mm out of true can be kept as well. It would be nice to have hook beads, but they usually don't. Aluminum wheels with bead hooks and moderate rim damage (a fixable flat spot or other crash damage) can be consider repairable if the spokes aren't too corroded, because they are very rare, especially if the hub is decent - and it usually will be if the rim has bead hooks..
  • 559 - Modern/Cruiser 26" or "26 decimal". These wheels are also in demand, but are we have a better supply of them because they are still in production and bikes with this size wheel commonly end up getting scrapped. All steel that isn't absolutely ready to ride goes to the backyard - we may end up using them, but they can wait out there. All the aluminums should have bead hooks, and any without serious rim damage that are less than 2cm or so out of true should be considered repairable, unless there are more than one or two frozen nipples.
  • 590 - Old 26" - Three speed or "26 fraction". Another size to be fair with. These are all going to be steel, and generally won't seem like anything special. Hold wheels with good three speed hubs, namely Sturmey-Archers, to a higher standard: if the rim has a decent dent, these wheels should be despoked so the hub can find a better future. Generally, keep anything around that seems trueable.
  • Other sizes. Most other sizes can safely be considered "oddball". One mildly notable size is the kids mountain bike 24" size (507mm). The rules for these should be the same as 559s. Road tubular wheels are rare, and also easy to evaluate: if there is anything wrong with the wheel that prevents it from being absolutely perfect, it should be despoked; all of its parts are high quality and could be useful. Kids wheels smaller than 24" are either fine or ruined - ruined could mean a big rim dent, a broken spoke, or frozen bearings. Loose bearings, cheap bearings, out of true, and corroded spokes are not a problem. Decent 20" BMX wheels are subject to standards similar to those of 559 wheels.

Tasks for apprentices

While an experienced volunteer can do the entire job, there are certain aspects which can provide a good learning experience for someone who is newer. One of these is lubricating nipples. After a quick initial inspection by an experienced volunteer looking for fatal flaws (mostly rim damage, but give the axle a spin as well), an apprentice can get the wheel in the truing stand and lube all of the nipples, then pick the correct spoke wrench and make sure they're all turning. The lube is necessary to check if the nipples will turn, and if they do, it will save some time for the person who trues the wheel later on. This can help educate the volunteer in the processes involved in wheel truing. If there is some confusion regarding the size of a wheel, a new volunteer can check the wheel using tires to determine its size. New volunteers can also be the ones to tag a wheel when it's finished, which will involve them in the evaluation process and show them what problems are common, both fixable and fatal.


Created by: pgarver. Last Modification: Friday 16 of June, 2006 20:29:03 UTC by pgarver.
The original document is available at http://www.ohiocitycycles.org/wiki/tiki-index.php?page=WheelEvaluation