Vintage Dirt Bike Q & A

Can I use an MT-125 primary drive gear and clutch housing on my CR-125? The MT uses helical cut gears while the CR uses straight cut gears. Could there be a problem with side thrust on the crankshaft and mainshaft? Are the bearings the same on both engines or are the bearings on the MT different to handle the side thrust? Any help from a knowledgeable Elsinore expert is apprec iated. Thanks.
Mark.

On my MT 250 the only things the side cover retains/positions are the kick starter and the shift shaft.

Both are shimmed for a pretty accurate fit. I used too thin of a gasket when I first put it together and both shafts would bind.

The MT125 has the same main bearings as the CR125. Yes you can use both the clutch and the crank gear on either bike as long as it has the matching type of teeth. The angled teeth are to make the motor run a little quieter. Side thrust from the angled gears is not a problem.