KH bearing size

I was going to get a profile hub and put it onto my KH but there are 2 bearing sizes and I’m not sure which one to use. The sizes are 6203-3/4-2RS (OD 40-mm) and 99R12 (OD 1-5/8 inch). Are they both compatable or does only one work on the KH?

The bearings I have that were supplied with a KH crankset have 6004Z stamped on the dust cover. They are 42mm outside diameter & 20mm inside diameter.

Hope this helps,

If I were you I would ask Roger Davies, I seem to remember him talking about KH bearings. Roger, are you out there???


My KH bearings are stamped 6004ZZ and their official dimensions 20/42 can be located at the following url. They have a lot of other bearing diemensions there are well.


I am now using a Profile wheelset in my KH (Taiwan made) frame. I used the 1 5/8" O.D. Profile bearings and a thin strip of shim stock. The Profile bearing is a close fit but you can’t use it without shimming to make up the difference.
It works great, I gave the MUni a proper thrashing this weekend with no problems at all.
I have photos of the shimming process. If you really care to see it, I’ll post them, but it is really a simple thing to do.
I used shim stock that a machinist friend gave to me but it’s just like a strip of a soda can.

sooo i can’t use my 2002 norco frame with the KH hub?

Re: KH bearing size

The Taiwanese KH frames with the KH hub take a 42mm OD bearing. The Taiwanese KH frames that come with a standard hub may have a different bearing size. The KH Pro frames take either a 40mm or 1-5/8" OD bearing. Some of the KH Pros are 40mm and some are 1-5/8", it depends on which manufacturing batch you get. So there is no simple answer for your question. Best bet is to call up and ask them what bearing size your particular KH frame has.

To fit a Profile hub in a Taiwanese KH frame with a 42mm bearing holder you’re going to need to use a shim. A simple shim made from a soda can should do the trick. You might also want to give a call to see if they have a custom shim to fit a Profile bearing in a 42mm bearing holder.

Here are two threads about fitting a Profile hub in a Taiwanese KH frame.

I’m not sure if Kris used 40mm or 1-5/8" Profile bearing when he added a soda can shim to the Taiwanese KH frame.