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Posted

I'm having a heck of a time trying to calculate the middle driven gear shim for my 87 Big Bear 350. I've followed the service manual and gotten all my numbers... but when I do the calculations, I always end up with a negative value... I'm so friggin frustrated!

As per the manual:
2BhaIhAl.png

My numbers:
d = 33
f = +08
c = 50.3
e = ???


wZrErrgl.jpg

I couldn't even figure out what my crankcase said... looked like gibberish! However, even if I took a guess at e, my answer is still negative because d seams like such a low value compared to the manual.

Posted

I  would contact  Yamaha and ask  them for assistance ...  Since  your  d  number is so  low ,  my  guess would be   it could be  124.33 ,  and  the  crankcase  number 12 (.12)

Please don't take those guesses  as accurate .. It  is  merely speculation on my  part.   Hopefully   you  can get a response  from  Yamaha  to  help  you .

Here  is  their   contact  page  for  Yamaha Canada .

https://www.yamaha-motor.ca/our_company/contact_us.php

Posted

I took another look and now I'm starting to think I'm trying to calculate the wrong thing. What I'm really trying to find is what size shims I need between the crankcase and bearing housing on the transfer case. The shims are number 17 in the diagram.

Iawmr5il.png

The manual has two different sections on calculating the middle driven gear shim. One using a feeler gauge between the crankcase and bearing housing and the other; the method in my original post. I'm thinking that I am overthinking this and that I should simply use a feeler gauge, rather than try to do whatever the heck my original post was about.

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