I have a 1986 VFR700. Fuel issue, turn key on and hear pump start, but get only a squirt of fuel then nothing. Is it the pump or the relay? How can I check both?
Unplug the main fuel line from the carbs (the one between the fuel pump and the carbs) .... route it into a fuel safe canister. Turn the key on, if it stops pumping then it's likely bad pump and it should be replaced. But .. before you replace it, test the relay per your service manual. Next, hook it back up with a fuel pressure gauge between the pump and carbs and check the spec with the book. If out of spec, it's a bad regulator on the pump and the pump should be replaced.
