Originally Posted by davek181
I have a spare set of 85 CR500 forks laying around. It is stepped also on the top. I measured the axle on it and it is 17mm in size. I compared the axle on an 87 model through an online lookup and they all use the same axle those years. So it is confirmed 17mm axle, 6003 bearings.
Cheers for confirming that Dave :)