1980 Yamaha starter question

[Tom7227]

My daughter bought a 1980 Yamaha XS 400 Special and the starter won't engage the engine when the unit is cold. Of course it is an intermittent problem. The starter motor will spin. When she gets it started and the bike is warm the starter works correctly. The manual she has includes repair directions but no trouble shooting. Removing the starter and reconditioning it doesn't seem overly complex. There is a centrifucal clutch mentioned in the manual and that appears to be more of a problem. E-Bya lists a rebuild kit for the starter for about $38.

Does anyone have any suggestions on what the likely cause of the problem is, and what needs to be repaired or replaced?

Thanks for any advice given.

[BradT]

This might not be your solution, but I would first try lubricating the shaft that the gear slides on. If you haven't tried it, I'd try this simple fix first. Use some white lithium grease. I had this problem on an electric start snowblower and all it needed was to be lubed up.

[moehawk]

Your one way clutch is what is causing the problem. It is attached to the rear of the flywheel. It works on three rollers and springs that let a inner hub spin one way. Sometimes one of the springs may break or just get gunked up and stick and allow the inner hub to rotate both directions. Pull the side cover off and flywheel (needs puller) and filp it over remove 3 allen bolts and the one way clucth will come off. Inspect rollers and springs. Its also possible their is some galling on the surface the rollers run on causing problem too.