Custom Clutch bar and Piston Skirt Trimming

reg454 said:

Some Mods I did while I had the motor off today and for the next week.

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the piston trim, is this done on the carb side or exhaust side,..?

reg454 said:

WOT is wide open throttle

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or it could be WFO (wide f@ckin open)

heyscuba said:

the piston trim, is this done on the carb side or exhaust side,..?

Click to expand...

Carb side only ..........

Hi there, I'm new to this forum but I have been keeping my
eye on it for quite a while. I've had my bike for about 3 years
now and I love it. The bike always seemed like it was under
powered though. I read about this piston skirt trimming thing
and decided to check and see how much I would need to trim
off of mine. To my surprise the skirt covered about 1/2 of the
intake port at top dead center. Out came the dremel and it
was trimmed. All i can say is it was like sticking a full race cam
in. I did nothing other than this to the engine and it has made
a world of difference in power.Hills I used to have to run at full
throttle to get up now are doable at half throttle and I gained
some top end as well.
I would recommend to anyone building a new bike to at least
give this a try hopefully you'll be as happy with the mod as I was

Don

the only motors i've seen with that much skirt over the port was a grubee. My Pk's are less than a mm of overlap. and the crown of the piston is less than a mm above the ex port floor. and to anybody trimming there skirt atleast remove the piston first. stuffing the case with a rag dont work verry good.

That's sound advice. As far as the type of motor I have is concerned,
I bought the whole bike off of a guy from work so it was already
assembled. I have no idea what kind of motor it was but the piston
covered a lot of the port.

Don