There is a difference between the UK/European kits and the US.
US kit part number 90891-10119-00.
UK/European part number 90891-10120-00.
The European kits do not contain the piston rings, 4th gear wheel and corresponding circlip.
I've checked with Yamaha UK and spoke to one of there Technicians.
His reasoning, although nothing official, was that most of the European bikes had just come out of the crates and would have very low mileage, any wear in the tranny / engine would be minimal.
The 4th gear wheel runs against the Pinion gear etc with the problem circlip, any abnormal wear to the gear due to alignment would only occur on higher mileage bikes.
Mine's a US import and I've covered 10K miles. So I have purchase the additional gear for the rebuild, just in case there are any problems with wear.
Ghostdog
Ride to live
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