Hi folks,
My Yuni muni with a 3" Gaz has unequal gaps between the frame and the
tire, causing the tire to rub on the frame on one side. Is there an easy
way to fix this?
Thanks,
-Jon
Re: Unequal wheel gap on Yuni frame?
Put a little bit of pop can underneath the bearing on one side in the bearing
cap.
Dylan
Dylan is on the right track. Don’t put it under the bearing, though. Put it over the bearing. When you find the right thickness, glue it into the maincap bearing holder that is welded to the frame leg. That way, even if you remove the wheel, the shim is always on the correct side. This is the way Darren shipped Tangerine Dream to me. He used a fiber shim and glued it into the frame. The nice thing about it was that he did the alignment for me so I didn’t have to measure it and do it myself.
In addition to possibly needing to put a soda can shim in one of the bearing holders, there is the possibility that both fork legs are not bent in the same amount. Depending on what hub you have the fork legs may have been bent in to be able to fit the hub. For example, the Suzue is a narrow hub and for the Yuni frame to be able to fit the Suzue hub the fork legs need to be bent in. If the fork legs were not bent in the same amount on each side then you may have wheel alignment problems.
See if you can determine if the fork legs are both bent in the same amount. If not then you can either try bending them in evenly by hand or you can take the frame to a bike shop that has a fork straightening tool and they can bend the legs evenly.
My esteemed colleagues have discussed two possibilities.
A third possibility is that the wheel is out of dish. When you go to the bike shop to check the frame ask them to use their dishing tool to check to ensure that the rim is centered on the hub.
A fourth possibility is that the tire is not seated well on the rim so that it bulges in places asymmetrically.
Check the fork alignment, wheel dish, and tire seating before you glue a shim in, otherwise you may not be solving the problem.
Ok. I’ve already checked the tube/tire for misseating; I pried one edge of the tire off, used copious amounts of talcum powder, and put it back on, with no visible effect.
It’s a Suzue hub, with the Kovachi-trued wheel, so I don’t think dishing’s an issue.
How do I distinguish between unequal frame tube length versus unequal bending.
-Jon
If you want some free shims, let me know.
It will solve the alignment for sure.
bedford_unicycles( at )yahoo.ca
Cheers,
Darren
A fourth possibility is that one of the bearings is not fully pressed on the hub. Flip the wheel around and if the gap appears on the other side of the frame then suspect that a bearing is not pressed on all the way.
Go for the shimming solution first. That solution is easy to undo and is likely to fix the problem. If you are unable to get the wheel centered with shims then look at the unequal bending of the fork legs. If the cause is unequal bending you’ll be unable to get the wheel centered and in line with the seat tube using the shims.
It could have been damaged in transport…
My Coker wheel came slightly off centre in the frame. After riding it for a couple of months it seems to have settled in place. However from what you have described it is more than a little bit off centre.
I recently had a similar problem, I had clobbered my Coker in a hard trail ride and a botched repair, the solution presented itself in the form of a tape measure and straight edge.
First true the wheel, tire off, then use a blocked straightedge to measure the relative distance from the rim to the bearings. also check to make sure the bearings are centered on the hub. From what you say I bet the wheel is already right, but no harm in truing a wheel while you are already pulling it anyway. If it needs dished, go ahead and do it.
Now comes the judgement part. Put the wheel on the uni without the tire and measure everything you can think of . Determine whether or not the frame is bent to one side. Fix the problem by bending the frame or using popcan shims.