cthenn

I just bought a new set of custom wheels and when I stick them in the frame, they are not centered. One is a few mils to the left, the other a few more mils to the right (the rear is worse, probably 3 mm to one side). I swapped them and the offset moves to the other side, so it's clearly the wheels. I never noticed this before on my other bikes, but my new bike has direct-mount brakes, so it's easier to see how off-center a wheel is because of the 2 equally spaced mounting posts. However, it's also a lot harder to center the brakes to account for any issues. For my other bikes, I can just rotate the entire brake unit around the single post and force it to be centered on the wheel. I maxed out the L/R adjustment screw and still had to move some spacers around on the brake shoes to get the brakes to hit the rim equally. I also checked a few other of my wheelsets, and some of the others also had some slight centering issues (wheels are true), though not as bad as the rear of this new wheel.

So my question is, how hard is it to properly dish a wheel and does it matter if they are slightly off-center? Wheels should be centered no matter what bike you put them on, right? Does a non-centered wheel present any potential problems/hazards while riding?

I took the wheels back to the shop I bought them at, but they just did some additional adjusting of the brakes in order to get them to hit the rim centered, but didn't seem interested in re-dishing the wheel. I'm not overly concerned, so long as the wheel is stiff and rolls well, and I can brake properly. So far, they seem to be nice, but I'm still curious as to why they aren't "perfect".

Andrew R Stewart 

If one can true a wheel then all the skill to dish is already had. A simple dishing check tool can be made from a few stacks of washers/quarters. Make three equally high stacks that are tall enough to support the rim with the wheel on it's side and allow the ale to clear the table surface. Place the rim on the stacks and measure from the axle lock nuts (or end caps) to the table top. Flip the wheel over and repeat. The two measurements should be within a mm or two of each other.

Don't forget to make sure that the QR skewer springs are properly installed. If their large end overlaps the axle end the wheel will sit crooked in the frame. Andy.

cthenn

OK, so the answer is it is easy to dish a wheel by a competent wheel builder, and shouldn't matter what frame the wheels go in?

And yes, I checked the QR, the springs are correct and the axles are properly sitting in the dropouts.

cny-bikeman

Anybody can dish a wheel. If the wheel is true and properly tensioned all that's necessary is to loosen the spokes on one side (typically 1/8 - 1/4 turn) and tighten the other side an equal amount. If it's low on tension one can also fix that at the same time by tightening one side more (or only tighten). A dished wheel will sit in the center of any frame, as long as the frame is not out of line - and that is rare.

Moe Zhoost

If you trust your truing stand to automatically center the rim, you are kidding yourself. I've fiddled with my Park TS2 for 30 years and have never got it to perfectly center a rim. You can get close, but you really need to use a dish gauge.

lvolpe

Glad to see someone else echo this sentiment. The Park stand is great for building a wheel but is essentially worthless for accurate dishing purposes no matter how often you adjust it. There is no substitute for a dishing tool.

joejack951

What do you guys consider accurately dished? To be honest, I use a cheap Minoura truing stand which has some laser engravings on the piece used to check vertical true. I eyeball that centered (it can slide side to side) using a known properly dished wheel (and reverse it and check again just in case) but I am eyeballing the whole time. I figure I get the wheel centered within less than one millimeter but seeing as how it matters not one bit (to me), I have never bothered to truly measure it.

hueyhoolihan

assuming the wheel is laterally true, i simply loosen all the spokes on one side a quarter or half turn then tighten the other side an equal amount and repeat until the rim is centered. the rear wheel is a little trickier, one has to keep tabs on overall tension, side-to-side after each round of re-tensioning.

and yes, i know it's not as precise as it could be (i don't use a truing stand either ) but it's proved to be close enough for 6000-8000 miles per year of riding, plus touring for 10 years on seven bikes worth of wheels.

Moe Zhoost

Your method is perfectly acceptable in doing your own. It sounds like you understand the limitations of your stand and take the time to make sure you meet your tolerance expectations. OTOH, I would expect a shop selling custom wheels to not just lace and true, but to spend another ten minutes to get the dish spot on. With a dishing gauge you can quickly get to <0.5mm

Dan Burkhart 

I'll note that adjustments made to the side with the greater bracing angle, ie, the non drive side, will have a greater effect on moving the rim. You can observe this effect during the final tensioning phase of a wheel build, where each round of 1/4 turn adjustments to all spoke nipples will cause the rim to move toward the non drive side.

RandomTroll

Dishing is easy. I made a dish tool from a stanchion of a discarded wooden TV table (a folding table one uses to hold an individual meal while watching TV) and 2 4-inch wood screws (3.5-inch for front wheels). It's hardwood, flat, the hole in the middle (where it attaches to its mate) fits the axle snugly, the 2 holes in the ends are at the right spot for my 700c rims; I'd have to drill holes for other sizes. A decent scrap of 1x2 would work.

elmore leonard

Edited for deletion.

joejack951

Ok. Whenever I hear 'perfect' regarding a wheel build, as in 'perfectly centered', I wonder what is really meant. While I'm sure hobbyist could sit for days getting trueness and dish 'perfect' (within the capabilities of their measuring equipment) I doubt it is something that is commonly done. <0.5mm seems like a reasonable goal if one has an accurate way of detecting that much variance. If and when I find myself building more wheels I might just have to buy a dishing gauge, or perhaps build a better stand that allows to me accurately dish a wheel.

_ForceD_

Thinking about this dilemma I wondered if maybe there might be axle spacers of inaccurate thickness, and/or if the problem can be solved with rearranging spacer thickness. So I did a search "dishing vs. spacers" and arrived at a discussion post on Cycle Chat that says:
"Re-dishing the wheel only make sense on a threaded hub, where the hub can be centralized to the frame. It's a pointless exercise with a cassette body hub."(https://www.cyclechat.net/threads/re-dish-the-rear-wheel-or-just-use-loads-of-spacers.127868/)But no one went on to explain why. I'm trying to imagine why there'd be a difference. I totally understand the purpose of dishing and how/why it's done. But can't a threaded hub and a cassette hub be dished alike? If not, why?


Dan

joejack951

You are getting confused by the somewhat unrelated topic being discussed in that forum. Because those guys are dealing with SS conversions, they have the option of the using spacers to centrally locate the hub within the frame. This means that they can build a rear wheel with no offset and even tension on both sides. They could elect to keep the hub slightly offset in the frame and have a slight amount of dish to the wheel, too. Cassette wheels don't have an option. The hub will always be offset and there will always be some dish and some tension imbalance. This configuration, while not ideal, has proven itself over the years to be good enough and continues to do so even with the extreme offsets required by 11 speed cassettes.