125cc Main Bearings

[Ron]

Hi Guys,

Does anyone use a caged bearing to replace the original style main bearings?

Are there advantges to the old style? Possibly the proper size is not available?

I getting ready to strip my cases for bead blasting and will need to buy bearings and seals.

I'm hoping to  build a vintage race bike, so originality is not all that critical to me.

Just wondering if there were alternative upgrades?

Thanks, RonW

[Doug Wilford]

Ron;
The original M-20 Main bearings are available.  With the proper fit they are the best to use for racing or whatever.   Remove all the bearings before you do any bead blasting.    The main bearing outer race you will have to heat the cases to get them to fall out.    I suggest you get all your clean up and blasting done before putting them in an oven.   I hope you have an understanding wife because they are going to make a stink.   After 350 degrees for 20-25 minutes they will come out by impacting the case on a block of wood.  Then before the cases cool reinstall all the bearings including the outer race of the main bearings. Note: The bearings come as matched sets so make sure you keep them matched.   Good luck and have fun.