Anyone seen this excessive wear on mvm belt drive pulley?

[Vern]

Recently blew a belt on my mvm drive and while changing I noticed the upper pulley had some play in it. The pulley would wiggle side to side a bit and would slide on the shaft about 1/16” or so. When I removed the pulley I noticed the backside of the pulley and the metal washer behind it were significantly worn into each other. I talked a bit with mvm when getting a new pulley and they said this is not common, which I believe as I’ve never read anything negative about any of the belt drives, but couldn’t say for sure what caused it. The drive was put on the sled at new and both had about 750 miles at the time the belt blew. I have noticed since replacing the washer and pulley that I can grab the secondary clutch and push and pull on it and the jack shaft itself will slide in and out of the bearing on the case side about 1/16”. It appears that the tcl moves with the clutch and jack shaft movement, and I’m sure this movement has something to do with the pulley wear but not sure how to prevent it. Everything was installed correctly. I’m just curious with all these belt drives out there if anyone has seen anything similar.

 

[kanedog]

I had a similar issue but from a different pulley maker. I think the vibrations from the engine are going to the Jack shaft causing funky issues with gear splines.

 

[Vern]

I figured it had something to do with the jack shaft having a bit of side to side movement. I’m just surprised I’ve never seen any mention of anything like this on the interwebs with as popular as belt drives are.

 

[kanedog]

I agree we haven’t heard more. I’ve never had issues with belt drives except for on the ascender chassis so maybe we are on yo somethong

 

[Vern]

I’m sure there’s been others with issues, people just don’t seem to like to give honest opinions these days, especially on popular products. Afraid they might hurt some feelings or possibly get their feelings hurt when the group minded individuals get offended.

I could see the cats having more issues though with the way their jack shaft has movement built in with the tcl vs the fixed shafts on the competition