piston porting


Local time
1:14 PM
Jul 20, 2008
has any body here lightened thier piston or window ported it it works good on my 26 cc and my 29 cc motors im going to be trying a few of these thing as soon as i get a couple extra pistons another 1 i like to do is zero drag crank seals as i go through the process i will post results if any one here has done this please let me know your results
Sounds like a nice project.
Any thing would help a happy time engine with engine vibrations.
it all adds up to the big picture

lightening up your piston wont mean squat at speeds under 10000 rpm.

any wieght you can take off of your rotating assembly will account for some thing if you know what you are doing you will gain throttle response and quicker accelleration not neccessarily more power just a cleaner more tuned motor in most cases !!!!

Sounds like a great project to me!....Just curious but if you lighten the piston will you also machine some off the crank to keep it balanced or would it be OK as is?

on a single cylinder engine lightning the piston will have no effect on the balance of the engine the crank is only counter waiting what it will take to follow through the compression stroke your making it easier to do its job by lightening the piston this is why you see performance gains
Igor has posted some stuff on this, http://www.motoredbikes.com/showthread.php?t=5516originally i "cleaned up" my ports, removed the base gasket and the "ridge" on the head, then I went with what Igor had said.

The outcome? 35 km/h half throttle and real smooth, less primary noise and chain slap, better mileage and ONCE got to 58 KM/H with the standard 44 tooth sprocket.
I'll have a guess and say you know a bit about 2 strokers, go with your experience man, hey, I blew mine by going to lean, lol, I know better, but "lean is mean" lmao
lean is mean lol ive been building 2 strokers for about 20 yrs and i think ive tried almost everything once its like no matter how well its running you just got to squeeeeeez a little bit more out of them thats what r&d is about im going to try to stuff my crank in december downtime by spring i should have a complete pro mod motor done and thanx phil for the link im gonna check it out !!!!
this does help alot it you could even drop the port a little to speed up fuel delivery this method is really effective with the right pipe also thanx fastboy for the link!!