350 or 265

[pcemkr]

Currently have a non powervalve CT 350 and I am considering replacing it with a 265 cylinder, what do you guys think. I normally ride pipelines and trails and the 350 just seems like a bit much

[TheFontMaster]

I was looking at prices for esr PV cylinder kits last night. What I didn't get was that a 265 cost as much as a 330, I would say go with a esr 310. Right in between the motor you have now and your 350. I think that you will deffinatlty miss the power of the 350 if you step al the way down to a 265.

[markk]

I dont know how u-all can handle that sorta power! I know that when i rode a 250r with a stock Cylinder pushed to a 265 it seemed to be a power house, Anyways he has since droped a PV cylinder onto it, and loves it! I wouldnt go BIG BIG, just for reliabilty reasons!

[Blown 331]

You could sell me your old set up for my ATC. I think that would be a handful.

[wilkin250r]

What kind of porting does your CT350 have? Perhaps the problem isn't really the level of power, but the delivery.

Most 265cc cylinders are heavily ported and dedicated to a particular riding style to get good power delivery, be it top end or low end. They are usually built to the max to make up for their lack of displacement. I think you would probably be happier with a 310cc with stock porting. It will probably have about the same peak HP as a heavily-ported 265, but better all-around power delivery, especially if used with a basic all-around pipe, like the ESR type 5, or even FMF Fatty, and probably a large head dome for relatively low compression.

Basically, with no porting, a basic pipe, and low compression, you can de-tune a 310 to the level of a 265, but not always the other way around. And if things change, you have potential with the 310, where the 265 is probably maxed out already. I wouldn't spend money to downgrade to a 265 unless you're meeting class restrictions.

[LT250Racer609]

if you do get ride of the 350 cylinder...how much do you want to get ride of it for? because i have a ported and polished 265 cylinder right now and i want the 350 for MX...perhaps you would want to change cylinders plus i give you some money???? just a thought....

[JTRtrx250r]

Originally posted by wilkin250r
What kind of porting does your CT350 have? Perhaps the problem isn't really the level of power, but the delivery.

Most 265cc cylinders are heavily ported and dedicated to a particular riding style to get good power delivery, be it top end or low end. They are usually built to the max to make up for their lack of displacement. I think you would probably be happier with a 310cc with stock porting. It will probably have about the same peak HP as a heavily-ported 265, but better all-around power delivery, especially if used with a basic all-around pipe, like the ESR type 5, or even FMF Fatty, and probably a large head dome for relatively low compression.

Basically, with no porting, a basic pipe, and low compression, you can de-tune a 310 to the level of a 265, but not always the other way around. And if things change, you have potential with the 310, where the 265 is probably maxed out already. I wouldn't spend money to downgrade to a 265 unless you're meeting class restrictions.

Im w/ wilkin!

[deathman53]

I ride a atc with a 330, I'm going to a stock(ported) 40 over cylinder, yes I will miss the arm ripping power, but It doesn't rev at all compared to stock sized piston and I have a cr ignition. The stock one is better for mx, 330 would be awesome for dunes and xc and my other issue is heat, the 330 runs hot. Its easier to wheelie the stock sized cylinder than the 330, seams hard to believe, the 330 is more like a tractor, while the stock a rev monster(setup right) and the stocker will jump on you more, the 330 needs time to build up the revs

[ESR350r]

I have the ESR330 with the 5mm stroker crank with the bigger carb and all that other stuff. I cannot tell too much of a drop in RPMS. It may rev just a little slower but once it starts it is all power. In most my races I keep it reved out alot and when it would bog down it always had the grunt to pull me up the hill or out of what I was in, and with a little slip or pop of the clutch you are right back in the power band ripping the tires off again. I have had some serious heat problems during a GNCC race and a hare scramble and the motor held up great through both races. The options you have for the heat is to run the bigger radiator or one of ESR's pipes that has the shorter stinger. ESR told me the trx 5 and 11 pipe are the same as running a bigger radiator plus you get the performance. I have never heard anyone with a temp gauge say how much a bigger radiator will drop your temp. I have the ESR gauge on mine right now and it runs around 200 playing in the woods, 175 or so out on the road where it can breath and well over 200 running all out in a cross country race. I would go with the 310PV motor instead of dropping to the 265. I have not heard of any heat problems with the 310PV

[deathman53]

unfortunitly with the atc, I'm kinda limited with options. esr only sells one pipe for it, and bigger radiators are out of the question.