Scooterotica

just curious but is there anything else on an engine that might cause a similar squeak each time piston travels up the barrel and what torque are people using on a standard 200cc set up for the cylinder head bolts ?

18ft/lbs for the head nuts

Squeaks can be a weird one. Does it do it while running and or rolling it over by hand? Could be about anything. I'd start with removing a piece at a time until it stops making weird noises.

Also, using grinding paste on an aluminium head is asking for problems (contrary to popular belief I know). The paste particles will embed them selves in the aluminium and make the metal harder and therefor making the head harder to surface and seal correctly. I have them cut on a mill so there is fresh aluminium on the mating surface and they are perfectly flat. No leaks ever.

You may be right but none of the ones I've done have ever leaked even with no gasket.

Guys, yes it was squeaking when I rocked the flywheel from side to side.....wondered if the crank running out might have caused it, but the flywheel isn't rubbing the mag flange so I'm thinking it's ok. I did rub the head and top of cylinder down on wet and dry on glass (to keep it flat) and tried them on the glass after with no 'rocking'. I also put sealant on both faces of base and head gasket (the red sealant for car heads...instant gasket stuff).

I have torqu'd head to the 18 ft/lbs but still the subtle squeak and yes can here when running. It pretty much starts first kick and idle's ok ....so I wondered if it was even an air leak. Only other thought was mag side gasket which I just put on with grease both sides, could it be from here .....

Annoying as this is the first time it's happened in 4 recent rebuilds ???

tried it again today, I'm not convinced it's a head gasket, just wondering if the big end bearing on the crank might be making the noise as it turns