Want more performance

sourdiesel404

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Joined
Oct 31, 2013
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cape coral
Hi I want to know where I can get a balanced crank and piston or is this something I can do myself ? I'm pretty mechanically inclined I work on my truck n bikes but never took a piston or crank out of these before
 
Arrow racing sells a balanced crank for a $100. and thatsdax sells them as well but I think you have to phone to get a price
 
My buddy drilled holes in his piston for performance he got more power but the piston cracked later on like 500 miles or so later
 
if you're going to remove metal from the piston I would suggest just carving the metal away from areas that it doesn't need to be. the intake port is a little bitty thing but the piston skirt there is a solid inch and a quarter wider than it needs to be.

on a reed valve bike you can make the intake side of the piston way way way lighter by cutting the intake side skirt almost completely away.

my preferred method of lightening the top end assembly is to drill out the wrist pin or switch to a titanium one. I've had bad luck in the past with commercially available titanium wrist pins (none of them are properly hardened) so I had a machinist buddy make one for me a while back and it's been working well. I don't know if it's because it's properly hardened or because I've been using a bronze bushing instead of a bearing that it's holding up. it's worth investigation to see if a bronze bushing with a commercially available titanium wrist pin will last.

and of course a properly trued crank makes a massive difference. a lot of cranks from the factory are tighter on one side, I've seen as much as 60 thou difference. just chinese manufacturing for you. I simply take the crank and stick it in a vice, then start cranking down on it until the runoff is too small to measure with my equipment. if I go to far, turn it over and pry it apart a bit.
 
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