how much power can i add if i put a staight pipe on my trx250 1985

 

You will most likley loose low end tourqe.If you put on a good aftermarket pipe & play around with the spacers you will get what you need .

 

Not enough power to out run the bullets people will be shooting at you for making too much noise. Like truck said, get an aftermarket pipe.

 

thanks i put stuff on it like new piston 12:1 how should it be running as in temp wise

 

By "temp" are you talking about exhaust temperature read from a gauge? If so, it doesn't matter what modification you do, the peak exhaust temperature should be the same. Maximum: 1150 to 1250 for a reliable play machine; 1200 to 1300+ for a frequently rebuilt drag racer.

 

no i mean head temp i haveing problme with it shuting down after i run it hard for an hour

 

o ya can i mix methonol with fuel and have higher octane and if so how much

 

No methanol unless you re-jet MUCH richer. Adding methanol will require you to rejet. I have a piston on the wall of shame from a guy who thought about adding methanol to his gas was OK. Methanol's octane rating isn't nearly as high as some may think, 100-105 ballpark.

Too high of CHT can be tied to lean jetting. Have you checked?

 

do you know y it keeps dieing

 

TRX250

I hope you're just a kid who's wasting our time, and hasn't really done these mods. You obviously don't have even a rudimentary understanding of what's required to run them.

With a true 12:1 piston, you will need to run straight race fuel, at least 110 octane. No methanol, unless you have a carburetor set up for it, and you flush it after every use. These questions are ones which you have asked in 3 OTHER REQUESTS, and they have been answered. You have also requested information about grips 3 TIMES. People on this forum are happy to help other riders and answer questions, but don't waste our time.

Even a rider with basic understanding of engines will know that a straight pipe does not give the necissary back pressure needed to run a regular four stroke engine to anything near peak performance.

Sorry, but I think it will be nice when the kids are back in school -- they'll have less free time on their hands, and only the ones who really ride and wrench will be on here.