The Diagnosis is >>>>>>

2 replies to this topic
  • G-Man

Posted January 27, 2002 - 07:43 PM


Performed major surgery on the beast today and found the culprit.

4th gear Pinion gear had a tooth completely sheared off. Going to replace the gear it engages too. A few other gears showed marks that look like machining marks, is this normal?

Also as mentioned before, replacing the clutch as the ring gear attached to it had a chip, probably caused by the tooth floating around.

I've been good about changing oil, (use the non-synthetic Yami stuff) so I'm not sure why this happened. I have missed a shift in a race before and had to slam it in gear, so maybe this is the cause?

Thinking about going to the Mobil 1, Im also concerned about will the trans be suspect now?
Has anyone had this happen to them, get their trans fixed and had the bike be trouble-free afterward?

Thx in advance.

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  • Hick

Posted January 28, 2002 - 03:59 PM


Make sure you get all the metal off the inside of the magneto and the inner oil pump and its pickup screen.

I put about 50 hours on my ’00 after replacing about everything and experienced no further problems, and I did the work myself.

Make sure the shifting forks are straight and the grooves in the shift drum are smooth, make sure the shift star is undamaged.

I mocked mine up and made sure all the gears engaged smoothly before I took the case halve back off, applied the Yamabond, and put it together for real. The tranny should go through the gears smoothly just by spinning the countershaft by hand and working the selector.

I don’t think you will have any problems, just be careful, patient, and thorough.

Easier said than done, I know.

Hope this helps.

  • G-Man

Posted January 29, 2002 - 07:31 AM


Thanks for the tips, some good info.

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