The jetting I think is OK because I dynoed it with 160 and 165 main jets and the power was about the same, slightly more with 165 mains (running 170 or 175 is noticable too rich just by riding it). Did a plug chop at the weekend on the circuit and it looked good. I've done plug chops a few times at the circuit and showed my plugs to resident 2-stroke experts and they always say they look good.
Top end rebuild was recent. I looked for that layer on the Daytona filter and couldn't see it. I'll look again.
I'll have to reconsider after the next dyno run, but thanks for all your advice.
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MC28 SE -sold-
MC21 with RS250 engine -for sale-
MC21 race bike -soon for sale-
