I am wondering if what would be the cause of my belt sprocket spline being stopped out. I have a 1989 XLH1200 when I bought it, it had been converted to a belt drive. I drove it for about 3 months when one day on a long ride I switched gears and heard a noise and felt no drive (like I was in neutral) so I down shifted and the sprocket cover broke and basically exploded. After inspecting I found the teeth on the sprocket had been shared off and the sprocket was slipping around on the drive shaft. I figured it was a flawed sprocket, bought a new one, replaced it, drove it for the season about half way through the next season a dog came from around a building in full on attack mode so before it got to me and tried to tear my ankle apart I shifted gears to get out of dodge and boom I felt the drive spine make dust of the sprocket splines again! (Lucky I had enough momentum to get away from the angry pooch) Anyway, I decided to go back to the original chain drive, that’s when I noticed a decent amount of play in the actual drive spline and figure the torque when shifting and the play in shaft is slamming and tearing through the teeth on the sprockets & before I have it happen to this new chain sprocket, I was wondering what would cause the slop in the drive shaft?

 

I also had an issue with a worn out drive pulley myself, but fortunately caught it before it left me sitting on the side of the road. Usually the problem comes from an improperly torqued, and fastened pulley.

After the pulley splines get worn, they slap around on the drive spline and eventually go completely.

What's your drive spline look like? Are the ridges well defined? If there is wear on the drive side, it could be causing the drive pulley to slop around and wear out quickly.

If you put the new pulley on, and there is any movement at all, it is probably going to do it again.

P.S. How did it manage to break the cover? Did the pulley itself break?

 

What causes slop in the drive shaft ? Thirty years of riding will do it . A loose primary chain won't help but usually it's just all the wear and tear on the gear dogs that adds up to produce increased play at the final output.

 

The first day one it happened the drive shaft must have caught the sprocket just right and it got catastrophic lol could have been worse! But yea everything looks tight no noticeable slip or wear between gear splines on shaft to sprocket fit. But I can move the sprocket back and forth and the shaft travels a good 1/2+ inches

 

Not unusual on an old bike , it's wear and tear in the gear box added to some primary chain slack .

 

When you say "back and forth" you mean rotate it?