PWK 39 mm

[New2Tri-Z]

What is the difference between a regular PWK 39mm
http://www.ebay.com/itm/CR500-KX500-WR500-YZ490-RM500-RM465-YZ465-CR480-KEIHIN-PWK-39mm-CARBURETOR-CARB-/130997444347?pt=Motors_ATV_Parts_Accessories&hash=item1e800e5efb&vxp=mtr

and the Quadvent PWK 39 mm?
http://www.ebay.com/itm/KEIHIN-PWK-41-5-MM-CARB-TRX250R-LT500R-CR-YZ-KX-RM-250-500-125-KTM-CARBURETOR-39-/321391358921?pt=Motors_ATV_Parts_Accessories&hash=item4ad46af3c9&vxp=mtr

I am running it on my z and having it bored to 41.5mm, but just curious the difference between the 2 units?

[Liquid-Darkness]

Man I stuck one of those 39mm PWKs in my 85 R a few years ago.. WHOOSH that thing hauled with that in. It jumped and misseld through the gears like a rocket. Lol. I miss those Rs.

[RIDE-RED 250r]

The standard PWK has the usual 2 vent lines where the quad vent has 4

[New2Tri-Z]

The standard PWK has the usual 2 vent lines where the quad vent has 4

Is there any performance difference between them? Is one design superior to the other? Thanks for the info so far.

[RIDE-RED 250r]

Is there any performance difference between them? Is one design superior to the other? Thanks for the info so far.


That's debatable.... The claimed benefit of the quad vent is that when one races on a moto track and hits big air and nasty whoops it is supposed to allow the fuel to settle better and faster and reduce or eliminate engine bogging when coming off such obstacles.. Or so I am told anyway.

My PWK Airstryker is a quad vent and runs fine on my big bore R. I don't run moto tracks or anything like that.

But the regular 2 vent PWK 36 runs fine on my other R as well.... Is it really needed for most of us??? Probably not....

I don't make it a point to acquire or avoid a quad vent carb....

I plan to upgrade my big bore to a 40.5 PWK at some point in the relatively near future... I have no worries about getting a quad vent or not. Whichever I find will do just fine for the kind of riding I do.

[New2Tri-Z]

That's debatable.... The claimed benefit of the quad vent is that when one races on a moto track and hits big air and nasty whoops it is supposed to allow the fuel to settle better and faster and reduce or eliminate engine bogging when coming off such obstacles.. Or so I am told anyway.

My PWK Airstryker is a quad vent and runs fine on my big bore R. I don't run moto tracks or anything like that.

But the regular 2 vent PWK 36 runs fine on my other R as well.... Is it really needed for most of us??? Probably not....


I don't make it a point to acquire or avoid a quad vent carb....

I plan to upgrade my big bore to a 40.5 PWK at some point in the relatively near future... I have no worries about getting a quad vent or not. Whichever I find will do just fine for the kind of riding I do.

Thank you Ride-Red 250R, that is exactly the info I was looking for. I appreciate your help.