Originally Posted by Scrad

Just checked and they are 3/32 IRS balls and I'm using a Kimbough gear. Diff works perfectly.

Edit... I was checking around and I see that it should be 1/8. Crazy. I wonder why my diff works. I have an old yellow IRS axle and that spur is about 3 or 4 years old. I know it is working because if I put new diff rings in it I'll see grooves in the rings. Wow... I guess I should use those 3/32 fballs for my Lazer.