Power Valve

[LazeR]

I have heard many things about power valves and have no clue what they do :confused: ! So basically my question is what do they do ?

[beak7707]

You can do a search on it, for a really good explanation. But basically it works off of pressure. At low RPM's, the pressure is low and the valve isn't open, thus restricting exhaust flow. The restricted exhaust flow gives the motor more low-end. When you start climbing up in RPM the valve starts to open and the pressure reduces, allowing the motor to rev higher. In other words you can have the best of both worlds with a PV. Good grunt down low and not lose any of your top end. Also the make the power band much smoother. Their is a lot more to it, but this is basically how they function. Like I said a search will answer your question better.

[Juggalo]

it should be mentioned that powervalves are only for 2 strokes.

[LazeR]

ahhh i finally understand lol! My friend just got his lt500 running and supposedly it has a powervalve in it. i had heard the term before and knew it was only for 2 strokes but being a curious person i had to ask what it does :eek2: thanx for info!

[Toadz400]

While we're on the subject...does anyone know if you could possible add a powervalve system onto a 2-stroke without having to buy a whole new engine?? I don't feel like buying a new engine for my Banshee but I really want to get a PV...:(

[TORO1968]

Originally posted by Toadz400
While we're on the subject...does anyone know if you could possible add a powervalve system onto a 2-stroke without having to buy a whole new engine?? I don't feel like buying a new engine for my Banshee but I really want to get a PV...:(

You'll have to buy new cylinders. I believe FMF makes a nice set of PV cylinders for the Banshee.

Any of you two-stroke experts have more info?

-Jordan

[wilkin250r]

Originally posted by Toadz400
While we're on the subject...does anyone know if you could possible add a powervalve system onto a 2-stroke without having to buy a whole new engine?? I don't feel like buying a new engine for my Banshee but I really want to get a PV...:(

The powervalve is actually molded into the cylinder. The actual "valve" portion is the exhaust port. Basically, you are asking if it is possible to replace the exhaust port without replacing the cylinder. You can keep the bottom end, but you have to completely replace the cylinders.

[Juggalo]

thats right, but he won't have to buy a whole new motor, just the top end. there are powervalve kits availible for banshees. in fact the street bike the banshee motor is derived from comes stock with powervalves!