I'm thinking about buying an ESR powervalve 265cc Nicasil coated cylinder. I will be using it with a Boyesen Rad valve, TMX 36mm carb, and an ESR TRX5 pipe. I will only be using this for fairly fast trail riding, and a couple trips to the dunes. This may seem like overkill to many of you, but, some other 250R riders will understand! Does anybody have any feedback on this??

 

Looks like a good package, I have an LRD prepped 350PV. I'm very satisfied with it, pulls very strong right off idle with no vicious hit, just strong smooth stretch your arm type power. Go BIG, you won't regret it....

 

38mm air stryker. get your exhaust flange reamed out a few sizes. i use 2000 rad valve for cr 250. don't know the diff but engine builder wanted me to get that one. my reed intake had to be opened up to accept it. which esr porting you getting?

 

Anything ESR makes is quality. I would step up to a 38mm carb though. Mine's a 38mm PWK from Sudco, and I love it. If you ride tight trails, I would suggest the TRX6 pipe. More low end would make it a little easier.

I've heard somewhere that a TRX5 with an adjustable exhaust flange(longer) would make about the same low end grunt as a TRX6. Does that statment hold any truth at all?

 

that set-up will have very very nice bottom-end
If you want a more "all-around" powerband get a 38tmx.

The boyessen is a bottom end rad valve
the 36tmx has ALOT of bottom end
The trx5 has everything.

But whatever you get, you will definatley have a nice motor!

 

Thanks for the input everyone. As far as what porting I will get, I just assumed that a pv cylinder was ported for top end, with the pv leaving you with some low end also. I'm not sure if I will have enough $ for the cylinder yet, I already bought the pipe and carb. If my wife found out how much $ is spent on this stuff, she would probably faint...LOL