426 transmission problems

4 replies to this topic
  • gscx

Posted September 23, 2011 - 10:18 AM


So I had to split my cases for a unrelated problem and while I was taking out my transmission I noticed that on the primary shaft 2nd gear and 3rd gear had some problems. The bike has been shifting fine but i knew that these two gears where on their way to failure soon. The cogs are in perfect condition, absolutely nothing wrong with them, so its not my shifting thats screwing it up? The teeth have spots in them indicating wear. Its really hard to explain, its almost like the metal is porous? And I can take my finger and flake off the smooth "coating"(?) around the porous part. Has anyone ever taken an X ray of these things? I know the older Yamaha's had transmission problems, maybe this is the reason?

Im just looking for A reason as to why this keeps happening. Once again the cogs are perfect and the bike shifts fine until the teeth bust off the gear. And Im only seeing it this time on the primary shaft, the driven shaft looks perfect.

  • gscx

Posted September 24, 2011 - 11:42 AM


no one has an opinion on this? I can get pics

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  • MNellis

Posted September 24, 2011 - 06:46 PM


no one has an opinion on this? I can get pics

I don't have any opinions on what your describing but I've got a whole transmission I'll sell for cheap if you need it.

  • gscx

Posted September 24, 2011 - 07:14 PM


I have one on the way but thank you. Ill keep this in mind though as im sure ill have more problems in the future

  • houndog426

Posted September 26, 2011 - 03:18 PM


The pitting is just wear it's just the gears way of saying it's gonna be missing some teeth soon. The pitting is actualy the hardness wareing off.

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