yamaha yx 600cc radian 1986.fuel tap constantly drips there fore flooding the carbs due to being positioned higher.I believe that they r vacume fed while engine running and only let by whilst in prime position.I have cleaned carbs and fuel tap system checked for damage and none found, still leaking on refit any ideas

piston bloke, April 2009

The fuel tap doesn't regulate the ammount of fuel in the carbs,no matter how high up it is.You've got two problems,the float needle valves are worn letting fuel bypass them,made out of nitrile,if i remember,like a hard rubber,and they do wear out.You'd probably get away with this if your vacuum tap was working right.take the small vacuum pipe of at the inlet stub and suck it,fuel should only flow when you,or the engine is sucking,if it's flowing either way the taps faulty,it keeps flowing,overwhelming the worn needle valves in the floatbowls.

MAX, April 2009

Check Flaot heights. Need to be right. If not I suspect the main Jets need renewing?

Billy Boy, April 2009