Straightening Spoked Rims

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BrnP84 · #1 Unread post by **BrnP84** » Thu Apr 30, 2009 9:59 am

I've been riding my 79 CB350 for a few months now and it runs great except the rims have a slight wobble to them. The front was really bad, it would shake the whole bike once I hit about 30 and my buddies tell me that the rear also wobbles but I can't really feel it. So I used the "ping" test on the spokes, hitting each one with a wrench and tightening or loosening until they were all roughly the same pitch, it seemed to work great on the front and it has a very slight wobble now but very much improved from before. The rear is missing a spoke and on 4 other spokes it looks like a previous owner replaced the spoke nuts? (the piece that connects the spoke to the outer rim) with some kind metal clamps that don't allow for tension adjustments. The spokes that have those clamps seems a little loose and I can't do anything about it.

Finally, my questions
How safe is this to be riding on? I can't really feel the rear wobble very much but I hopped on my buddie's bike to look at my wobble and it's pretty bad, if I had to estimate I'd think 4-6mm. The front seems pretty true now. I'm also having trouble straightening the rear rim b/c of the missing spoke and non adjustable spokes, should I compensate by not tightening the opposite side?

RhadamYgg · #2 Unread post by **RhadamYgg** » Thu Apr 30, 2009 1:00 pm

Welcome to TMW!!!!

I'm not going to be very helpful on your topic though. One of the reasons I go with sport bikes - when I bought my Kawasaki Ninja 250 over the Honda Rebel had to do with the fact that wire rims on a motorcycle scare the crap out of me.

I wouldn't ride a bike with a wobble, if I knew about it. Once when I hit ripped up highway on 287 N approaching the turnpike the front wheel seemed to do maximum deflection to both sides while I was still moving straight.

Like you the solution was to slow down.

edited to say: Oh, slowing down isn't a permanent solution to the wobble and I probably would be uncomfortable with it doing things like that. But then again, I spend most of my time at highway speeds and that little wobble at 30 mph would be crazy at 80.

RhadamYgg

TorontoBoy · Thu Apr 30, 2009 2:52 pm

Spoked wheels are a feat of engineering due to their simplicity and utility. They actually change shape as you roll down the road.

That being said, each and every element of the wheel (rim, spokes, spoke nipples) plays a very crucial part. If you have 4 loose spokes in your rear tire you may experience a catastrophic failure at the worst time. Broken spokes can grab your chain and lock up your rear wheel. I would get these 4 spokes replaced (may be easier to purchase a rear wheel on eBay) before getting back on your bike.

For the front wheel you can get a spoke wrench to tighten and true the rim, as you have partially done. It's not that hard, and the results, with practice, will be good.

#4 Unread post by **Wrider** » Thu Apr 30, 2009 4:20 pm

First off it can be very dangerous to ride with a wobble, much less a rim that's missing a spoke and has 4 in bad shape...
So you're going to want to replace that spoke ASAP and make sure everything is ok with the rest.
Secondly get a pair of jackstands and a metal bar long enough to thread through the axle and be supported by the jackstands. Then get a dial gauge, and measure how much runout/wobble you have. Factory specs call for .5 or less mm of wobble and hop. If you can't do that, have someone who can do it for you, it's very important! It will affect acceleration, braking, cornering, weight capacity, everything about the bike.

BrnP84 · #5 Unread post by **BrnP84** » Sun May 10, 2009 5:40 pm

thanks for the advice, I think I'm going to take the bike in and get it the rims looked at.