Wheel bearing loose/wobbling in rear wheel?

[Nessism]

The rear wheel on my second 1000S was moving side to side/wobbling and the problem turned out to be a damaged wheel - the aluminum fretted away under the drive side wheel bearing to the point where the bearing was loose. Ditched the wheel and bought a different one from ebay, and now that one has the same problem, only to a lesser extent. Has anyone ever seen this problem before?

I cleaned up the better wheel really well bonded the bearing into the wheel with loctite bearing and stud lock. Seems to be holding for now but I'm not holding my breath. Need to find yet another 18" wheel, but before that I'm going to talk to a machinist friend to find out if he can bore the wheel to take an oversized bearing or sleeve. Bad luck.

 

[salty_monk]

Don't see any problem with boring it for a sleeve. Make it a press fit....

 

[Dogma]

I don't see a problem with sleeving it either as long as there is enough wall left around the bore. I want to know what caused the wear in the first place. The outer race shouldn't be moving once the bearing is pressed into the wheel.

The only plausible theory I'm coming up with is the bore in the wheel somehow got stretched a little, resulting in too light of a press fit. Possibly a PO tried to install a bearing and got it pretty well crooked hammering in one side at a time. Or when hammering one out. Two munged wheels in a row is unlikely, but not impossible. I would say much less impossible than two bearings (probably from different runs or even manufacturers) being manufactured undersized.

 

[Nessism]

I'm struggling to understand what happened but this damage did not occur while changing bearings or due to a malformed bearing. The wheel bore where the bearing sits is literally worn away so there is a recess and the bearing wobbles - one wheel is worse than the other. I'm seriously wondering if the bearing is large enough to handle the torque loads. There is lots of meat on the wheel to take the bore oversized; the bearing is 47 x 20 and the next size is 52 x 20 so I'm going to talk to my machinist friend here at work. He can bore the wheel easily but chucking a motorcycle wheel on the companies equipment is a different matter.

 

[salty_monk]

If next bearing up is readily available may be easy to go that way.
Soft casting not helping I expect...
I guess with a sleeve you could put a steel one in which should prevent this happening again.

I have some wheel bearing somewhere ( not new and new if you want to do size comparisons.

 

[TheCafeKid]

Wouldn't an improperly installed spacer or set of spacers Allowing the wheel to walk on the axle cause some bearing shift? If at one point, on those older softer casts, someone didn't tighten their axle nut down tight or missed a spacer or something that didn't allow the swinger to squish all of that together tight it may have been the culprit perhaps?

 

[Nessism]

Wouldn't an improperly installed spacer or set of spacers Allowing the wheel to walk on the axle cause some bearing shift? If at one point, on those older softer casts, someone didn't tighten their axle nut down tight or missed a spacer or something that didn't allow the swinger to squish all of that together tight it may have been the culprit perhaps?

This could have something to do with it. I noticed that when one of the bearings was seated all the way down to the bottom of the wheel bore and the inner spacer installed, the inner spacer was too long to allow the other bearing to be installed all the way down to the step into the bore in the wheel like the other side. At any rate, I think there are issues going on here which allow the drive side wheel bearing to walk around and fret in the wheel bore.

 

[Dogma]

I'm struggling to understand what happened but this damage did not occur while changing bearings or due to a malformed bearing. The wheel bore where the bearing sits is literally worn away so there is a recess and the bearing wobbles - one wheel is worse than the other. I'm seriously wondering if the bearing is large enough to handle the torque loads. There is lots of meat on the wheel to take the bore oversized; the bearing is 47 x 20 and the next size is 52 x 20 so I'm going to talk to my machinist friend here at work. He can bore the wheel easily but chucking a motorcycle wheel on the companies equipment is a different matter.

What I meant was that the bore may have been damaged during a bearing swap, which then allowed the bearing to move when the bike is ridden, causing the fretting. As you say, a botched installation alone wouldn't cause fret marks.

In your response to Josh, you mention that the inner spacer is too long to allow one bearing to seat fully. Side loads on the wheel might be enough to move things around and cause the fretting too. Did you transfer this spacer from the first wheel? I like this better than my first theory.

 

[bwringer]

Wouldn't an improperly installed spacer or set of spacers Allowing the wheel to walk on the axle cause some bearing shift? If at one point, on those older softer casts, someone didn't tighten their axle nut down tight or missed a spacer or something that didn't allow the swinger to squish all of that together tight it may have been the culprit perhaps?

^^^ Yes, this, X1000. Something is probably wrong with the spacer(s).

I've seen this happen before and lead to the same results. You can also see something similar from bearings that seize and spin (damaging the axle, the wheel, or both), but in that case the cause is pretty obvious.

 

[Nessism]

I'm going to order a double row ball bearing because it's 6.6mm wider than the regular bearing, which will expose some virgin wheel bore to hold the bearing snugly in place. I wouldn't try this on the severely worn wheel but it's worth a try on the slightly worn one. A machinist friend recommended dimpling the worn section of the bore with a punch to "knurl" the surface (raise up the metal) which will tighten up the fit of the bearing, and then using some bearing lock compound to further secure the bearing in place. With the wider bearing the drive side external spacer will have to be narrowed but that will be a simple matter.

To repair the badly worn wheel I'm thinking about boring the wheel to the next bearing size (from 47 mm to 52mm). The hub has lots of meat on it so going oversize like this shouldn't hurt anything.

I still don't understand how or why this happened. I hear you guys regarding the spacers but nothing was wrong or missing in that regard yet there were two different wheels with the exact same concern.

 

[hampshirehog]

Ed, I've seen this on a few bikes. It's common (ish) on bikes that have a circular ring nut that is tightened to hold the bearing in place and where that nut hasn't been tightened up fully. I guess some people get confused as normally one side is a LH thread and the other is a RH tread. As your bike doesn't use this I'd just guess that someone didn't tighten the wheel up at some point which would have a similar effect.

It might also be worth measuring the OD of the bearing. Despite quailty assurances they do vary a very small amount and as they're a 'whack-in' fit the previous bearing may have been tight followed by one with a slightly smaller OD. I tossed a new bearing on my 1000 last year as it was a soft push fit and replaced it with another new one that was tight (forgot to measure but there was a definite difference).

Your suggestion of knurling the hub and using Loctite red ( I assume you guys have the same colours - this is ours for bearing lock) is a common fix if the gap isn't too bad - maybe 0.2 mm. You could use the 'next one up' - Loctite green which is very strong though you might never get that bearing out again. I did the 'knurl and red' on my mate's A10 a month ago and it's fine.

The other method that is common is to bore the hub out and fit a sleeve - sometimes a deep bore / sleeve to allow for a double bearing (especially on old British bikes). Your other idea of the 52mm OD bearing also seems good.

 

[Nessism]

Loctite and Three Bond makes specific products for securing bearings, although I'm not sure how much different they are from the standard thread locking compounds. At any rate, I'm moving forward with the repair(s).

Found some double row Angular Contact bearings for a fair price so wanted to ask if there is any downside to using AC bearing compared to a regular double row ball bearing for this application. I don't think so but you guys may think differently.

 

[Dogma]

AC bearings trade some radial load capability for more axial load capability. So long as each row of balls is of similar size and count to the single-row bearing you're replacing, you should have plenty of radial capacity left. It won't roll quite as easily, but you're already going down that road with the double row. Just a little more drag, and a little more heating.

If the balls are significantly smaller or fewer than the single-row stock bearing, then we'll need to break out the catalogs and calculators.