Hello all I have a 1994 vfr750 and had a backyard Mackinac do some work on it (new tires and brakes and he supposed to have cleaned the carbs) well when he had the bike on a lift running off a bottle of gas it ran fine and started every time. but when we took it down and put the gas tank on it it keeps bogging down when you ride it , we took the tank off and emptied it (thought there might have been water in it, and put it on the bottle again and sure enough it started right up and revved up fine and to be sure I also put it in gear and it seemed fine while it was on the kickstand. and as soon as we put the gas tank back on and did a test drive its acting up again any thoughts will be help full thanks
possible plugged tank vent? It's rare but people say it happens. pull the fuel line off the carbs and do a fuel flow test. Factory service manual specifies a minimum flow requirement.
Tink, he needs to start with measuring fuel flow into the internal strainer, pick up tube, then through the petcock to the outlet tube through the fuel filter into a bucket, i tink, before it gets to fuel pump, doesn't he ? Is there another tank vent besides the one usually built into the filler cap ? Even with a blocked vent the bike should run fine for two or three minutes from startup i'd guess. Even with only 2 gallons of fuel in the tank, the outlet flow stream should be strong and steady without spluttering, something your urologist would approve; and with a full tank, it should flow impressively. Try blasting come compressed air into the tank outlet with the cap open to clear possible crud.
