On a XS650 crank the center bearings are a Koyo N type - AKA ther are slide out outer race type. They have the W modification - meaning they are drilled for lubrication circulation.
Other than that, their OD is 67.8 mm or 2.67 inch.
ID is 31.6mm or 1.23 inch.
Width is 17.1mm or .66 inch.

So anyone know what its design number is. Like 6303 etc ...

Cool.
Buddha.

Sure. 6303 sounds about right. 




































PS. what are we talking about? 
lol

Those are weird dimensions.  You measuring a worn-out bearing?

No it is a very nice and very useable bearing. In fact all 3 on my crank are, but I am thinking of swapping the inners cos to get them out I have to grind and press open my crank - cos its getting welded after getting rephased.
Anyway, Its the best of the 3 I measured, I also didn't measure with a cheap ass caliper ... so its not funky readings either ...

An - 6303 ... that is what I throw at people who try to steal my sheite ... this one aint even close.

Cool.
Buddha.

Closest 6000 series is 6306, and that's way off.  Last 2 digits you multiply by 5 to get ID in mm.  I think 2nd digit is duty class.

Oh sorry I forgot, it has the number 06N0702W-1 KOYO stamped on the races.

Cool.
Buddha.

I think you've got a custom bearing there.  Koyo's catalog lists standard metric sizes in N bearings.  ID on press fit bearing will be about .001 x basic shaft size smaller.

I see in the manual its a 32X68 X 17 bearing.
The SKF CRL10F is close, not sure what else ... and I have my doubts there have a XS650 only bearing ...

Get this, I can buy it new anyday from a place specalising in XS parts called mikesxs ... its 85 bones a pop.

And, they are selling the other crank bearing for $75 ... and I managed to find that in the parts list, spec-ed it to a 6306NRC3 and found them for 15 bones a pop (standard 6306 is cheaper, but needs 5 mins in a lathe) but the 6306 NRC3 is straight drop in and costs $3-5 more.

The trick is to get it in terms of universal numbers. I am working on it, if I get that I am sure I can find it for 10-20 a pop.

Anyway my other thing is I am finding a crank for the thing. So if my crank comes back from the welder looking like a pretzel, I'd just stay away from modding the crank and just buy the other crank and fit it back together.

Cool.
Buddha.