Middle gear adjustment-- easy and effective

[lnewlf]

Yup- I once ruined a pricey Scheffer 411 gearset in my 340 Duster by shimming to tight....got real hot real fast..

 

[mjlovstrom]

I went down in shim size one at a time, and then checked the " backlash" and then rode it to hear the result. As I would go down in the size of shim of course the slop would be diminished in the gear set, and the backlash felt at the output shaft was of course be less as well. On my bike with 80,000 + miles ending up at .15 shims reduced the noise, and I still had backlash in the output shaft-- but I stopped there. Would I go any tighter without actually measuring, probably not. But after a lot of miles those gears will be worn to a point where adjustment could be made if wanted.

 

[lnewlf]

generally if one gear is reshimmed the other needs to be reshimmed too...changing the shim changes the contact patch between the two gears...machinists dye should be used to make sure the mesh pattern is correct...

 

[mjlovstrom]

I suppose, but in the factory yamaha service manual it is mentioned as a middle gear adjustment and only mentions the external shims that need attention.