Why You Shouldn’t Overfill Your Motorcycle Fuel Tank

When filling your motorcycle fuel tank, whether filling up for a long ride or just heading off to your daily commute, many motorcyclists top off their motorcycles just like they do their cars.  Overfilling your motorcycle fuel tank can actually be detrimental to the running condition of your motorcycle including stalling or hard starting. As most consumers, you take your motorcycle to the nearest dealer to fix the issue, the problem is once the fuel level has gone down, the dealership has no clue as to why your motorcycle is having issues.

California model motorcycles were once limited to the State of California.  Many new motorcycles are actually 50-state models, so they meet the California emission standards but are sold nation-wide.  The California motorcycles come with an evaporative emission system designed to collect and store fuel vapors, but these systems are not designed to deal with excess fuel.  So if you overfill your motorcycle fuel tank, the fuel can enter the fuel-vapor separator and then eventually the rest of the system, thus resulting in stalling or hard starting.

How to Fill a Motorcycle Gas Tank

The best way to prevent this problem is to read the instructions in your owner’s manual for refueling.  When you fill your gas tank, the fuel level should barely touch the bottom of the fuel tank filler neck. This is how to fill a motorcycle gas tank the right way.

Trained motorcycle technicians will look for the following signs if you are have hard starting or stalling issues:

o       They will check for raw fuel around the roll-over valve and inspect the canister as outline in the Service Manual

o       They will check the evaporative emission system hoses and make sure they are not kinked or pinched

o       They will inspect the canister.  The canister has finely ground charcoal in it; if they remove the canister and rattle it, it should not sound like a can of spray paint.  If they do hear that sound, the charcoal may be clumped up from the excess fuel in the system which can clog the hoses

o       Finally, they may bypass the evaporative emission system so they can test the vehicle and see if the emission system is the problem.

So, next time you consider topping off your motorcycle gas tank, the extra little bit of gas you put in may cost you quite a bit more down the line when you have to pay for costly repairs.