Ok im asking this question for a friend in the philippines that one:: Doesnt have internet access Two:: Speaks bloody bad english

So my mate has a Track NC with "the" tap mod, He did 4-5 races with no issues and now from what I can understand, the Diaphram is being pulled away from the round plastic spacer in the tap inself causing the fuel channel to be blocked... So he said he has taken the tap apart again pushed the rubber diaphram through the plastic spacer all fitted up and the bikes works A1.. Then after being stood for half a day the Diaphram has been pulled off the spacer again!!!!

The only thing I could think of that would cause this would be a vacuum build up in the tank causing the diaphram to be "sucked" back into the fuel hole!!! Anyone else had this issue???

I myself have run this mod for sometime now with no issues and I havent heard of it happened before?????????

Please dont turn this into a flaming thread regarding this mod either!!! Help need only

Is the tank breather working alright?

Erm its supposed to be done on a track bike so no need for flaming :D

As mark has said.. either the tank breather is blocked causing a vaccum lock or the tap mod was done wrong...

Just got off the blower to him!!!

He has blown the tank breather through with compressed air and did the mod alla http://www.akhara.com/nc30/fueltapmod/index.html As we all have..

Fcuk knows what it could be ???

No one else had this issue then???

had this problem just before a track day. IIRC, you need to remove the plastic piece completely. Can't remember for sure, but I think the only piece you need is what is required to seal the tap body. You then take a drill bit the same diameter as the fuel outlet ID and carefully drill through the little "wall" that the vacuum diaphragm would normally seal against. This basically makes the fuel tap mod a permanent one, but it keeps you from ever having a fuel flow problem. Just make sure you turn the valve off, or preferably install a dry break!