Hey. This is my first bike and my first post. I Just purchased a 93 900RR. The bike has been sitting for about 1 year with out starting. I know it needs a tune up, but what would be the reason for it blowing out gasoline (Alot of it)? There is a breather line of some sort located on the right lower part of the tank. Im not sure if its connected to the tank or the carb. But thats where im getting a leak from. Any Help would be appretiated. Thank You.

 

You have a stuck float. The exact same thing happened to me. Just remove the needles and make sure the rubber coated tips are not warped. Also, there are four ribs down each side of the needles. I had a bunch of gunk on mine that I could not wipe off. Instead, I gently rubbed it clean with water and 1200 grit sandpaper. It works fine now.

If you've never torn into carbs, it can be a bit scary--it was for me anyhow. But read the manual and be carefull not to lose any of the pins or manhandle the plastic floats and you'll be OK.

--Chris

 

Actually, it may also be a bad spark plug that is not firing off the fuel. I would change the spark plugs first and if that doesn't fix the problem, then tear into the carbs.

--Chris

 

I don't know about how spark plugs could be affecting fuel coming from the breather vent...

But I've got the same problem you have. My problem is because I'm moving too great a volume of fuel through my carbs before my fuel pressure regulator opens up and starts dumping fuel back through the return line. I'm running an overkill fuel system that can support up to 500hp and I'm still working out my kinks. The floats aren't able to shut down the flow into the carb bowls and they end up overflowing out through the air vents, which in your case are still tied in together with the breather hose. A float that won't rise and therefore close off fuel intake into the carb will allow for the carb to overflow. So this could be a stuck float, a float with a leak that takes on fuel and is no longer boyant, or you're somehow putting too much fuel into the carburetors and the float(s) can't handle it.

 

When I had this issue, I had the firing order wrong. Hence, some of the spark plugs were always wet and did not fire. When this happened, I puked fuel out the breather. But at the same time, I also tore into the carbs and cleaned the float needles, so It's hard to say which one did the trick.

If it were me, I'd swap the pugs out fiorst because they probably got wet and won't work well again. If that didn't get it, I'd break the carbs down. Pulling carbs from the bike must be a pain in the ***.

Teardrop: Are you using your breather as a fuel return to the tank?

--Chris

 

Tear drop, huh? The breather line is an air line, and in this situation it needs to be pressurized with dynamic pressure. The fuel return line is from the regulator.

 

My mistake! I meant drop top. Thats a bit embarassing. I get the fuel return now. So when the regulator gets enough pressure, it dumps the excess back into the tank...

--Chris

 

No problem.