Replacing KZ750 Balancer bearings is it possible?

I had a bearing failure contaminate the oil and glitter is everywhere in the bottom end of the engine. Its in all the bearings. Most of these bearings are available, however the balancer bearings are not ( 92046-048 ) I haven't been able to find NOS bearings other than one lonely bearing on ebay for $60 that clearly has surface rust on the rollers. The manual states that if the bearings are removed they must be replaced. This had led me to hunt for a new cases. I bought some used crank cases but it was destroyed in shipping. however, the bearings appear to be in good shape. I cannot find generic replacements because these have a oil groove on the OD of the bearing.

I'm wondering if it would be possible to remove the bearings by heating the cases in the oven. If this would enable me to reuse them in my good cases. Thoughts?

No eBay APP ID and/or Cert ID defined in Kunena configurationHere is a second one:

If the material the bearing is made of can tolerate the heat, then it is doable.
That means no discoloration of the metal. Or you could as long as the new
cases are unusable is to cut out the good bearings.


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The manual says you can install them by heating the cases but it doesn’t make any mention of the bearing being able to take heat. I like your idea of cutting the bearings out of the broken cases.... plus then I wouldn’t have to polish anew set of cases. Not sure exactly how I will cut them out though. Gonna spend quite of bit of time on a band saw I guess

Still pissed about those cases. The seller threw a complete bottom end in a giant cardboard box with butcher paper for packing. At some point it took a hit so hard to bent the shift shaft and broke the boss on the cases.

DoctoRot wrote: that clearly has surface rust on the rollers.

Two thoughts. One is that it may not be surface rust. I could the cosmoline like stuff Kawasaki covered their bearings with. I know the swingarm shafts I bought had brown goopy stuff that cleaned off.

Second, I can find similar needle roller bearings with "machined ring". However, the one catalog I looked at didn't have the exact size. I'm assuming based on the numbers on the picture you show, your bearing is 24mm ID, 36mm OD, and 20mm wide?

This one is not right, but similar.
www.skf.com/ph/products/rolling-bearings...s/productid-NKS%2024

Of course, some of the pricing I noticed was similar to the NOS parts on Ebay, so it might not save you that much.

Have you tried to flush out the bearings already in your case really well? As long as the rollers are not damaged yet, then it's just a matter of getting the glitter out.

If you do start baking things, here is the temp data page for that bearing I linked to. It says it's rated for 120C, and that the steel cage is also rated to that temp. It's a reference point anyway.

www.skf.com/ph/products/rolling-bearings...re-limits#cid-465663

Thanks for the link. I thought about cleaning the bearings out really well, but because these have a tiny little oil gallery that feeds them I don’t know how I would be sure I got it all out. The tolerances for the balancer are not super tight so it’s less critical than the other rotating compenents . I’m not sure how I would quantify if they were damaged or not

DoctoRot wrote: The manual says you can install them by heating the cases but it doesn’t make any mention of the bearing being able to take heat. I like your idea of cutting the bearings out of the broken cases.... plus then I wouldn’t have to polish anew set of cases. Not sure exactly how I will cut them out though. Gonna spend quite of bit of time on a band saw I guess

Still pissed about those cases. The seller threw a complete bottom end in a giant cardboard box with butcher paper for packing. At some point it took a hit so hard to bent the shift shaft and broke the boss on the cases.

Cut around the bearing like a pie with out touching the bearing.
Hammer, chisel and a punch to knock out a piece of the pie.
Should cause the case to spring open around the bearing.


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