You ask we answer. Here's the latest in our "Ask a Mechanic" series.
Q: I have just discovered fuel leaking from my 2008 Honda CRF450. It's not a lot actually, just the outside of the carb had moisture residue that turned out to be fuel so I know it's leaking somewhere. Any thoughts? Bike still runs and no other problems.
A: If you by chance tipped the bike over too far then that might be your problem which puts you in the clear. However, if not, you might need to change the carburetor O-ring which seals the carb and float bowl. These often get overlooked and after a number of years finally wear out causing the fuel leak. Sounds like you might have found it before it really started dripping, if that's the case.
Replacing this O-ring is pretty simple. Just drain the fuel, remove the carb, remove the bowl (usually 4 screws), remove the O-ring or gasket and replace with a new one. On most float bowls there will be a jet access plug that also has an O-ring - replace that too. It's best to buy a rebuild kit and do the whole carb while you have it off.
