Powervalve Cylinders

[hy250r]

dOES ANYONE HAVE A dUNCAN PC2000 KIT OR ANY OTHER POWERVALVED CYLINDER ON THEIR 250R?
IF SO HOU DO YOU LIKE IT? WHAT SIZE IS IT? cAN YOU NOTICE A DIFFERECNE BETWEEN STOCK BORE TO THAT?

[outlaw#9]

yes ... i have a 330 pv and the difference over a stock ported is huge !

it was a 350 before i had to resleeve it and that was even faster

i defenetly recomend a 8 plate clutch set up and the harder tranz gears if you can swing it :o

my bike runs down ALL 4strokes on the track ...just gotta learn how to hold on to it :rolleyes:

[wilkin250r]

I have a Duncan PC2000 340cc powervalve motor. HUGE increase over the stock machine. The big-bore makes huge power, and the powervalve gives a very smooth powerband.

[hy250r]

THAT WAS THE KIT I WAS WANTING.EXCEPT I WANT THE 275 KIT
BUT YOU'RE 340, HAVE YOU EVER HAD THAT IN THE WOODS?

[wilkin250r]

I am in the high Nevada desert. No woods around here.

My 340 has monsterous power, but still very manageable with powervalve. I would imagine the 275 to be much the same.

[250R Baja Rider]

I have a 265 PV ported by LRD with National Porting.
This thing rips and pulls really hard. The power is so crisp.

The transition between low end, mid and top is much smoother.

[hy250r]

yeah I cant even imaigine how much power that 340 PV will have. I only weigh 130 ounds so that thing would kill me.

I heard that Duncan has to do something called center-casing with a 305 and a 340, whats that?
I have been having a hard time on thinking if I should buy one becuase my friend told me that he rode a 250r with a PV and he never noticed a difference with his stock 250r.

[wilkin250r]

The cylinder has a sleeve in it that fits down inside the engine side cases. This sleeve can be bored out for a slightly larger piston, but only so far. If you want a REALLY large piston, you need a really big sleeve. Problem is, the really big sleeves don't fit into the engine cases anymore, so the engine cases need to be machined to accept the larger sleeve.

That's what Duncan means when they say center-casing. You will need to machine the cases for the larger bore.

[wilkin250r]

The powervalve really won't add that much unless you are an experienced rider in woods or MX racing, where low-end power is needed. In fact, they make riding a 250r a little less fun, because you don't get that hard hit and rush of acceleration.

My girlfriend hates my powervalve. For her, the excitement of a 2-stroke is that hit when the power comes on. Although my 340PV is faster, my stock motor has a harder hit, so my stock motor is more fun to ride.

Just because a powervalve is good for racing, that doesn't mean it's best for all types of riding, or all types of riders.

[deathman53]

I love the powervalve 310 on my atc250r, it hauls ***, but it wears me out quick. With the other mods I have, that much power in a trike is a absolute rocket to ride.

[LT250Racer609]

are any of you or anyone you know selling any size power valved cylinders?? because im looking to buy one for my 250R....would even consider a non-power valve 310 cylinder, 330 or 350

[deathman53]

I have a 330 for sale, It was beadblasted(guy was gonna buy it, but I don't know what happened). It needs a piston, all gaskets and rings are with it, it is ported for low to mid and you NEED a long rod to use this. $500 shipped.

[LT250Racer609]

is the head included???

[deathman53]

yeah, the pc burned off the head, when my crank seals went and caused it to overheat(thats why its on the first bore now) the head is gold in color. the cylinder has since been bead blasted and hasn't been touched, it looks 1000% better


http://pictureposter.allbrand.nu/pictures/deathman53/IMG_0589.JPG.html

[250R-Dee]

deathman .. if you have some better pics please send them to turbodee@gmail.com because I am interested in that cylinder/head.