what to do esr310 kit or stock build to 265

[250rRyan]

I bought an 88 250r quad that was set up for flat track. I want more power out of it. The cylinder was ported out but they resleeved it and back to 66. bore. My riding style is little of everything dunes, woods, ice racing, and mx. Should I stick with that cylinder and bore it out to 265 and a base plate then add a powerhead with race gas dome. My other thought was just buying esr 310 kit. If you have a good idea what i should do or something better let me know thank you...

[C-LEIGH RACING]

When that stock cylinder was sleeved, did they match the ports back to how it was ported before, or just left the port windows in the sleeve uncut.

If uncut, then getting that cylinder ported would be the cheapest route.
Anytime you go to a bigger size piston, that will give you just a bit more power, but not as much as jumping to a big bore all at once.

A ported 310 ESR top end kit is 599.00 + the spacer plate & shipping cost.

In your case with the stock cylinder, would be nice if you had a cool head to go with it so you could change out the dome when you wanted to run pump gas or race gas, + if you got the o ring type sealing head, that would do away with any problems dealing with a head gasket.
Neil

[250rRyan]

I think they ported the window when resleeved. I put the quad back together last year and still running but before winters over I would like more power out of it. thank for the info

[86 Quad R]

since you do quite a bit of riding that uses a lotta upper revs, i'd suggest a re-portin' for that cylinder to match a crank built with a longer than stock rod, no spacer plate, about 200 psi compression and match all the bolt ons(pipe, intake carb ect) accordingly. :cool:

[250rRyan]

Pipe thats on the R right now I believe its a curtis sparks 2 peace if that sounds right. The silincer that has no markings of what it is. What pipe and silincer brand the best out there or you recomand. I had other R before that had the fmf stuff and just bored. 10 or 20 over .