View Full Version : 1990 750cc

05-14-2008, 02:44 PM
Hi all!

I've been having trouble with my 1990 GSX 750 after I first get it started. It stalls really easy. I had a college buddy stop by and take it for a ride. We are thinking the problem might be with the spark plugs. Those are cheap so I'll go ahead and pick 4 replacements up and install them this weekend when I give it an oil change and oil the chains.

Out of curiosity, do any know what PRI stands for? It's on the switch on the side where you can switch the gas to "On," "Res (reserve)," or "Pri." We were taking off the gas tank to try to get a look at the spark plugs and left it on Pri and had a bit of a leak. We quickly pluged the hole and switched it back to "On" and it stopped leaking. That seems counter-intuitive to me. Why wouldn't "On" leak?

Thanks guys!

PS. I ordered some stuff from newenough recently and put katriders for the donation thing.

05-14-2008, 02:45 PM

05-14-2008, 02:49 PM
The petcock uses engine vacuum to permit the fuel to flow in the run and reserve positions. When it is placed in prime, the fuel will free flow - when you've run her completely out of gas, or the bike has been sitting an appreciable length of time, and the fuel has evaporated out of the carbs. Those are the only 2 times the valve should be placed in prime. The run position is where you should always leave her.

05-14-2008, 02:49 PM
when the petcock is in the "on" position, you need vacuum in order for the fuel to flow where the prime position will allow the fuel to flow freely.

05-14-2008, 02:59 PM
Did you make sure your choke is on? Choke cable connected? maybe also check the idle screw is not set too low.