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Hello. First post so here I go:

i have just successfully rebuilt a Honda MC19. New pistons, new rings. Valves and head done by a professional. New spark plugs. Everything is put back together to spec. I broke the engine in and it runs and idles fine. The carburettor has new jets and gaskets and a new fuelfilter. Took it for a spin to do a first high rev test.

First problems noticed, opening the throttle fully seems to feel like it loses power. But having it open at about 80% potential is fine.

Then lastly, the rev only limits to 14k and can’t seem to go past that point. A friend reported it smokes a little bit when accelerating, grey colour but not really noticeable.

i started off with the basic check. I check the fuel mix, all at 2 1/2 turns according to the manual. I checked for vacuum leaks but can’t seem to find any indications, even spraying WD-40 at the boots and around the Carb. They are all sync respectively although could be a little bit better I suppose.

I checked the coils and leads and all seems fine.

i suspect fuel pump as it does make a whiny noise. or worst case scenario, blown head gasket but no smoke really comes out.

another thing to mention. the timing of the valves is half a tooth off, which I spent many hours trying to perfect it but can’t get any closer. Could this also be the cause?
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