XJ900 Rear Wheel Obsolete Bearing - Work-a-Round (hopefully)

Long winded story (mostly finding an engineer who didn't sneer at me for such a small job)

My rear wheel on the XJ900 had a bad bearing, which also ate out the wheel hub a bit so it has been a bit wobbly to ride on.
I bought a 2nd hand wheel and tarted it up (paint), haven't fitted it yet, but it looks good... needs a tyre on it still.

Finding that bearing for an affordable price is not possible and I figured there must be a way around it. We can't just throw away our XJ900 because of a single custom Yamaha bearing surely!

Bearing: 93302-20306-00


Basically I eventually got a chap 'Precision Shims' in Australia to make me a spacer $33AUD out of tool steel and use an off the shelf bearing to be the actual bearing with a spacer on top, so to speak.

NSK 3203B-2RSRTNG $55AUD
or
NTN 63203LLUNTN $62AUD
To be fair I bought both these bearings in 2021... and I took the Yamaha (KOYO) bearing down to 2 different bearing places and they sold me these. In other words I put my trust in those guys.

17mmID x 24mmOD x 3.5mmWidth




Here are some pics of it fitted.
The idea was to use a false axle and put it in the wheel while fitting so the spacer was in alignment.
The axle would pop the false axle out of the final drive.
But... I don't think it is necessary as the spacer can't actually fall too far out of line anyway... even so I have made one if it is an issue.

I can't see any real reason that this won't be okay as the funky bearing just bridges the gap... but we shall see in the future I guess.

 

Good work!
I was aware the rear drive bearing was rare and expensive, this is an excellent solution.
Was just keeping my fingers crossed mine didn't crap out, but they're generally pretty long-lived.

 

Nice work and write-up!

Although.......I'm still curious as to why Yamaha would have specified such an odd bearing if such a simple solution was possible. Back in those days, manufacturers were much less likely to specify super-duper "propriety" custom parts (to replace standard off-the-shelf parts) as is all the rage nowadays.

P.S. the XS1100 / XJ1100 also use a cylindrical roller rear wheel bearing on the left side, just like the 900's....and then the R1/R6 models in the early 00's.

The rationale for using roller bearings instead of ball bearings is typically due to the the higher load-handling ability of rollers (both axial and/or radial loads) than ball bearings. Swingarms and steering stems (and the clutch pivot shaft in the clutch cover) also use roller bearings...all of which can have axial displacement (in-and-out rather than just round-and-round) loads.

But it's odd that Yamaha used them for a while on the rear wheels of some models but not any others...........they had a reason, that's for sure, but I don't know why.

 

As you say, greater load carrying capacity, but otoh my higher-mileage GS doesn't use them; final drive bearings are original and over 300K now.
Yamaha being cautious, I suppose.
Now that I've seen how to get around the shortage/price of the larger bearing, I'd be quite happy to use a shorter Koyo in its place, with a spacer. I've been using nothing but Koyo in my wheels for well over 30 years and never had one fail. They put up with surprising loads and keep on going.