so i was looking on the internet today, and I found a company that makes a bigger piston for the trx 250ex. my question is would it be worth it to bore out my cylinder head to install this bigger piston? and how much power would I gain by doing this mod? would this mod be worth doing? thanks.

 

If your doing it for more power; nope.

 

ok thanks for the help. I will skip the bigger piston then. and just go for a new exhaust and jet kit instead.

 

ok thanks for the help. I will skip the bigger piston then. and just go for a new exhaust and jet kit instead.

 

sorry for the double post computer screwed up

 

Kinda goes in this order for power. Exhaust,airfilter, rejet (big three), then cams, high compression pistons (not larger bore but just more compression), port and polish head, then bore the head for more power. Once you bore it then you have to do a few other things to get the most out of your bore. IMO

 

Once you go messing with the internals of an engine, the reliability factor (for which the venerable EX engine is famous!) goes down the toilet!

The little EX doesn't really have the suspension to handle a lot more speed anyway, so do the basic mods, and if that isn't enough for you....well just move up to a bigger better handling machine.

 

okay thanks for the help guys I'll put a aftermarket muffler on and rejet the carb for the new muffler and go from there. I already have a k&n air filter on it.