Honda TRX250R Forums banner

pipes and big bores

4773 Views 9 Replies 8 Participants Last post by  Pest
who makes a good big bore+porting compatible pipe? i've heard bad stories.
currently have a ptr '98 eliminator pipe on a 87 wondering if it can handle 300+ cc?
and what's the best way to get 300cc straight bore or bore/stroker?
main usage will be sand

thanks for any advice
1 - 10 of 10 Posts
As for the pipe, I have an ATV sport article on Chad Lohr's open class duncan quad. He was using the PT race pipe and the PT eliminator on a 340cc engine. I don't know if that was a newer version of the eliminator though. You could call duncan and ask them if your pipe will work okay.

On a stock cylinder, lrd and others offered a 300 kit using a re-sleeve and a 72mm piston. That would be cheapest route. You could also get a new 310 kit which also uses a 72mm piston. Lastly you could use a smaller bore and a stroker crank and achieve 300cc. Call some different engine builders and get their thoughts. ESR likes to build strokers. Some builders don't.
who makes a good big bore+porting compatible pipe? i've heard bad stories.
currently have a ptr '98 eliminator pipe on a 87 wondering if it can handle 300+ cc?
and what's the best way to get 300cc straight bore or bore/stroker?
main usage will be sand

thanks for any advice
If you are under or around 300cc's I would say your best bet is a Sparks TT or ESR TRX-5.

Here is a pipe test done by Dave Moore at Dave Moore Racing:
See less See more
Is that graph showing a trx5 standard mount or center mount?
Is that graph showing a trx5 standard mount or center mount?
I believe it is the center mount.
been a lot of pipe chit chat on here lately. this is the biggest dyno comparison of pipes that ive been able to find. its on a stock motor, so the HP numbers are especially weak for the high rev pipes, but it gives you a basic idea of power curves, and dead spots.

http://www.atvsource.com/articles/product_...dyno_charts.htm
i like the esr trx5 centermount which i just picked up. it looks really trick and everyone has good things to say about it. i am running it on a 340pv right now. but sparks pipes are also very good as well.
I really liked my sparks tt pipe. When I first went with the 350pv that is what I ran. Then I ran across the CPI 800 bb pipe. So I bought one and what a difference. It didn't loose any bottom end but everywere else it pulls like a crazed ape. You can really tell when the pv opens and it gets on the pipe, since your arms are ripped out of their sockets.
I really liked my sparks tt pipe. When I first went with the 350pv that is what I ran. Then I ran across the CPI 800 bb pipe. So I bought one and what a difference. It didn't loose any bottom end but everywere else it pulls like a crazed ape. You can really tell when the pv opens and it gets on the pipe, since your arms are ripped out of their sockets.
I have never heard of that pipe from CPI and do not see any info on their website. Do you have any pics or additional info?
You have to call them, they are special order only
See less See more
1 - 10 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top