Hi ! I want a light quad that has lots of power. So I plan to buy a 250r this winter...
what are the biggest modifications I can do on the motor without killing the reliability ?
I saw one with a 350 powervalve... 70hp. Should I go with a 330? 310? 282? 265?
I need: 1- Power
2- Reliability
thanks

 

I think you will always lose SOME reliability with a big bore, but most of the kits for the R are quality, so as long as you do proper maintenece, you shouldn't have a problem. Also, if you just want power, check into a Banshee. They are also very reliable with proper maintenence, and light mods make them absolutely scream!!! I personally wouldn't go with anything bigger than a 330, but that just my opinion. (I think) MP racing can adapt a CR500 cylinder onto your 250R bottom end, price s right around $3K, but that is some serious HP. Good luck with whatever you decide and welcome to the board. Also, if you have a question, chances are it's been asked already, so try searching for it before you post if you don't want to get flamed.

 

go with a 310 powervalve from ESR.... they bolt right in with no case splitting... first I would make sure your bottom end is nice and tight... so it can handle the power... as long as you maintain... it will last a long time...

 

Thanks ! That's what I'd liked to hear...
yeah I thought about the banshee but its 397 lbs... too mutch weight for me and its less maniable
....remains that it pulls his carcass quite well.. hehe

Hey pendejo, how it is to ride atc's ??

and when you talk about light mods... like what ?
pipe, v-force & spacers, head domes, big carb, air filter.. what else ?
you think I can get *lots* of power with these ? cuz if I can stay with the stock bore..

 

well..... you can take your cylinder now... give it a fresh bore.... have it fully ported by a reputable shop..... throw on a cool head, v force reeds, air stryker carb, and a good exhaust sytem...... it should rip!! as long as you maintan and have a good shop do the machining... you will have no problems with reliabilty.