how much performance would a stroker crank give me with a 88cc cylinder piston sik50s cam stock carb fmf pipe k&n air filter and rev box do you think?

 

You're not going to get the most out of the setup you have described until you ditch the stock carb. Adding the 18mm or 20mm carb will really wake that engine up.

 

A stroker crank or a 20mm won`t perform that great unless you have better cylinder head. The intake port on a stock 50 head very small. Its about the size of a pinky finger.

 

well i can put on the head myself, but heads are frickin expensive.
and i gatta ditch the bottom end stuff because it simply wont last its not strong enough
i HAVE TO get a heavy duty clutch plate/springs down there.
so well im down there i gatta get other stuff put in because that is cheap and i dont like working on the bottom end of the engine myself. and i know someone who does that for a reasonable price. so im ganna get that done. so im lookin for other mods before i do the head. and i dont want a wimpy xr70 head i wanna get a 4-valve head or something, know where i can get one