Interesting. It appears to me that the small groove in the edge of the larger gear's teeth is nothing but a nick that happened during manufacture. The gear teeth themselves look great and the hobbing marks (gear machining method) are still very clear indicating little to no wear.
The smaller gear is apparently showing a decidedly odd pattern though and it extends all the way to the gear teeth tips. Nothing should ever touch the teeth that far out.
Thanks for taking and posting the photos and posting the results of the transmission re-work. The best of luck with the bike from now on- hopefully the mechanic(s) just got a little sloppy with fairing reassembly but buttoned the engine cases together properly.
Brian
Update : got the bike back
- 2nd and 6th gears were changed. Gears were wearing out, causing freeplay which led to the noise.
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- Please check the attached pictures. one of the gears you can see where metal is chipping off and its formed a kind of groove. In the longer run it would have broken.
