Leaky Airscrews

headcoats · Post by **headcoats** » Sun Dec 04, 2011 1:40 pm

Pulling LC apart for the winter fettle and noticed that my airscrews are leaking premix

Anyone else have this problem ?
They are KR 28mm PWK carbs
Runs fine and had best dyno result to date a few months back

I have a Mikuni 42mm carb on me Buell

and i noticed that the airscrew on that has a little 0 ring on it

JanBros · Post by **JanBros** » Sun Dec 04, 2011 6:59 pm

just an alergic reaction from those Yamaha-parts, nothing you can do about it really ...

on topic : there is no O-ring, it is not nescessary, as the airscrew is on the intake-side, and only air passes.

headcoats · Post by **headcoats** » Sun Dec 04, 2011 7:09 pm

Is it because they can't handle the 61BHP

dave32 · Post by **dave32** » Sun Dec 04, 2011 7:19 pm

Persnoally ive never heard of them leaking before,is the screw wound out 2 turns or more?
Might be worth adding a couple of turns PTFE tape to the thread if they have to be out more than 1 and 1/2 turns.

headcoats · Post by **headcoats** » Sun Dec 04, 2011 7:50 pm

They are at 1 1/2 turns out
Maybe the carbs are spitting back a bit

dave32 · Post by **dave32** » Mon Dec 05, 2011 2:52 pm

Are you running open carbs then?
if your using a filter(foam or S and B type) then spitting back shouldnt get past on to the carb.
Ive just fitted a set on my 350 and am running foam ramair filters,havent road tested yet but feels promising.

headcoats · Post by **headcoats** » Mon Dec 05, 2011 3:14 pm

Running Ramairs on little extension tubes
I'm thinking the unburnt fuel oil mixture is settling in the bellmouth area then running down into the little hole where the airsrew screw/needle is