90 cc engine changes

[Hetrick Racing]

Hope this hasn't been posted yet if so sorry for the repeat.
Changed a 90 into a 106 yesterday.
Stock engine internal changes are.
Full circle crank,Machined rod for clearance.Interesting part engine measures 42x52 and the cylinder deck is the same as 09,Factory installed 2 base gaskets to raise the transfer ports,no power gains of course.
.
Stock cylinder is ported from the factory(not real good) only exhaust work.The stock head takes a bunch of work to make it worthy
Cases are slightly different,only have to remove .015 to clear 48 stroker.
Rear clutch has a monster red spring,with red shoe springs.Rear pulley same as 2003 smc needs modified.
Shoe pack is a boat anchor,belt and variator,same as 09didnt weigh rollers guessing 4.0 or 4.5.
Ill post more as I find it

[hotquads1]

is it the same head as in 09'? several of the 09's we pulled down had a squish of less than .020 from the factory (trying to raise comp), I would think a double base gasket would of dropped comp a bunch.
Marc

[bulldogfallon]

Lou did mention that there were some 90s with the heavy oem clutch...I think he is swapping them out upon request.

Great info....Keep it coming

[Hetrick Racing]

I think the extra gasket is to raise the port timing, squish was at .042
The head was very similar to last years with a bunch of worthless material,that i cut out.

[wrhracing]

And this is the 2010 model?

[Hetrick Racing]

yea Billy this is the 2010 stock 90

[hotquads1]

Rich, did you notice the 90cc came with a 28mm pwk carb ?
Marc

[Hetrick Racing]

I didnt see it until I was building a limited for a customer.
Joel has been helping in the shop(which is great) but when I asked him about the carb he just said it looks like the same one.
To stick up for him it does kinda.LOL
Great input though mark,the limited I built didnt like the jetting it came with(with the new filter) stuck a uni on it ,tuned way easier.