1978 to 1982 front wheel swap questions

I parted out a 1982 kz650 CSR. I'm restoring / changing up my 1978 kz650 B-2. I'm wanting to install the 82's aluminum front wheel onto the 78's fork's, but.............

The axels are different. So the 82 wheel will not bolt up to the 78 forks. Does anyone know if the hubs are machined the same on these two wheels ?? And would it be possible to install wheel bearings for the 78 hub into the 82 hub, so I could use the 78 axel on the 82 wheel / hub ??

Since you have both wheels at hand, you could measure the bearings. Alternately, the folks at Allballs could likely provide the bearing dimensions. Fork swapping might be the easiest solution.

Could you not Just swap the complete front end,Forks,brakes and all?

Yes swapping the complete front end is an option. But it's a last resort for me, as the 78 gauges wont be a simple swap doing that, and the 82 gauges are junk.

I did some checking and found the....
78 wheel bearings to be 17mm ID x 40mm OD x 12mm W
and the 82 wheel bearings are 25mm ID x 52mm OD x 15mm W

So I need wheel bearings that measure 17mm ID x 52mm OD x 15mm W to be able to swap the wheel and have it fit the 78's axel. All the wheel bearings I found online with these measurements are for automobile alternators. I'm not feeling comfortable running alternator bearings as front wheel bearings.

I also found that 17mm x 52mm x 16mm bearings are more plentiful, but there listed as alternator bearings also.

I'm not a bearing expert, and am not sure where else to look for a bearing the size needed to make the swap. Does anyone else have any idea's ? Is it a good idea to possibly have spacers, or bushings made and pressed into the bearing boar to change up the boar size to be able to fit a different bearing into place ?? Just thinking out loud here........

and the 82 wheel bearings are 25mm ID x 52mm OD x 15mm W

You may need to double check that info. The 650-CSR Fr axle nut is 14mm & I think the bearing ID is 15mm..

www.allballsracing.com/index.php/contacts

Are the 1978 spacers and speedometer drive going to work with the newer wheel?

Is the brake rotor going to line up with the caliper? Are the rotors the same overall diameter?

martin_csr wrote:

and the 82 wheel bearings are 25mm ID x 52mm OD x 15mm W

You may need to double check that info. The 650-CSR Fr axle nut is 14mm & I think the bearing ID is 15mm..

You are 100% correct martin_csr !! Jesus, I spent hours on the internet looking for the wrong size bearing :woohoo: Thanks again for guidance !!

Now I see I am in need of a 17mm ID x 42mm OD x 13mm W bearing. So far I see that this size bearing is a lot harder to find than the wrong one that I wasted so much time looking for.

Thanks for the link TexasKZ !! I'm going to see if I can find anything through them. I thought this would be an easy task.......

If you can't test fit the wheel using one of the axles, I would use a long bolt from the hardware store. 1/2" x 10". Or maybe a threaded rod or wood dowel.