is there an actual one we can buy because i dont like the vacum operated one i went to the mx track went and jumped the tabletop and then when i land tire lock up it loses fuel and stops it then comes back but there is no way i could win a race with it so is there anyway i can fix this it hapens at most of the big jumps it didnt do anything in the rythm section and i was only jumping it and landing in the middle of the tabletop but when i land boom tires lock up i go forward any help.....PLEASE

 

Leave it in the prime position when it is running. Just put it back to on when your done or it may flood your motor.

 

Buggybrian- have u actually done this on a Z or are u just speculating. Id rather have a real fix than leaving it on prime. Just kinda sounds like that might lead to some other poblems. Not sure though Im no expert

 

thats excactly what i was wondering

 

First off, I had a '89 gsxr 750 that had a vacuum petcock and never had the first problem. I think you guys are over thinking the situation. The only way the valve is going to close is if the motor stops pulling a vacuum (engine stall). The prime position bypasses the vacuum and puts constant pressure on the diaphram. In essence the "ON" position. And like any other bike while not running, the on position can cause leakage past the needle and seat and flood the motor or flood the floor. If you want to be sure put the valve on prime and go hit the same jump. More than likely it is carb related rather than petcock.

 

Something else to think about is even with the vaccum valve I really doubt that just because the tires are locking up that it would cause the motor too stall, because the carb has a fuel bowl on it and in that short of a time at landing you would not empty that bowl of fuel to cause it to stall, plus as it was stated earlier that as long as the motor is running it will create some vaccum so I would look at something in the carb itself. Just my thoughts.

dads400

 

its the carb slide its vac operated but when you land momentum closes the slide and you get your stall it allso couses missing on the whoops get a fcr