I have a 2001 CBR600f4i with 5,500 miles on it. It ran perfectly until it sat unridden in my garage for a year. Why did it sit? I have two children in diapers....but that's beside the point. The battery had died, so I replaced it with a new one and took the bike out for a spin. Yes, the gas was also one year old. I got about 3 miles from home when the bike started to sputter and misfire. Applying the throttle resulted in a rumbling feeling with mushy acceleration. Sensing a 3 mile walk home, I turned around and headed back to the garage...misfiring all the way. When I parked my very observant neighbor says, "Hey, your bike's on fire." Sure enough, I had about a 3 inch flame coming out of the exhaust. Simulataneously, the engine quit. I glanced at the temp gauge as I ran for the hose...."177." No obvious damage to the bike, but I'm a bit scared to try to start it without a firetruck nearby.

Any thoughts? Should I just take it to the shop or does anyone have an idea? Will new gas solve anything or did the old gas cause the problem? Should I try a fuel injector cleaning solution? Any help would be great. I am not a mechanic and beyond do it yourself oil changes, I don't usually do my own mechanic work. Thanks in advance!

 

my first guess would be you fouled out a plug on your ride. Doing this introduced unburned fuel into your exhaust. It must have built up in the already hot exhaust and ignited. That would also explain the rumble and lack of acceleration. I would pull all your spark plugs and check them. Also, while the plugs are out, crank over the engine to clear the engine out.

Doing this will also rule out another possibility. If gas continues to purge out of your cylinders as you crank it over and it never clears out, you more than likely have a bad fuel pressure regulator, or a stuck injector. I would lean towards the fuel pressure regulator as this is fairly common.

But, with the bad gas, it hard to tell what happened. In the future, you may want to either drain the tank, or at the very least use a good fuel stabilizer if the bike is going to sit for an extended period of time.

you could also try to remove your fuel pump fuse, crank it over and see if it tries to start. If it does, then your cylinders are flooded with gas. Crank it over until it doesnt try to start, replace the fuel pump fuse and try it again. If fires up and runs poorly, shut it off and remove the plugs. There is also a way to check the fuel pressure regulator, but Im not sure what it is.. Im pretty sure its a measure of resistance, but I would post in the F4 section as well. You may get more answers there.

 

Thanks! I posted it in the f4i forum as well and the overall opinion there is the fuel regulator. Like you said, I guess it is a fairly common failure. Looks like I'm off to see a cycle mechanic.

 

If you try to start it w/ the throttle all the way open the computer will not put any fuel in. It's a good way to clear it out or prime the oil system after a change.