My motorcycle runs badly when low on fuel, is this caused by dirty fuel lines or filter?

Question

Bike has a carb.

Even after I switch to reserve, problem persists, like its out of gas, but it still has about a half gallon in there. Seems to run fine on full tank. ??????

Answer 1

newer bikes, like my '95 virago, have a 'reserve' switch, not the old petcock device...when the electronics (the TCI) receives a 'low fuel' signal, it just allows the fuel pump to pump at about 50%...making you realize you gotta do something.  You switch the reserve switch, and the tci allows the pump to pump normally...maybe your switch is bad, or the wiring in that circuit, fooling the tci into not switching back into normal mode.

Read all about it at the dr piston site...he's talking about viragos, but you get the idea.

Answer 2

Perhaps restricted petcock.

Remove the fuel line from the petcock.

Put a cup under the petcock (or attach another hose and aim it into a cup).

Turn the petcock to on and then to reserve - the fuel should flow at the same rate.

Answer 3

You probably have a bit of debris in the bottom of your tank. When it gets low, the gunk get's pulled through the fuel system causing it to run nasty. Get your tank flushed and cleaned.

Answer 4

Drain it and put fresh gas in it, and drain the bowel on the carb, ya know what floats on water? gas.

Answer 5

I would guess lack of fuel.

Remember it is sloshing around in your tank, and could be stuck on the right side of the tank (on some models). Leaning the bike to the left side while stopped will help get the fuel over the backbone hump in the tank.

Could have a clogged reserve inlet to your petcock. Remove and look to find out.

Answer 6

Sounds like you have water in your gas tank.  As the level gets to a certain point, you've got more water in the mix than gas.  Water is heavier than gasoline and will sink to the bottom, when your tank is full the percentage of water is low, but when the level gets below 1/4 then you're pushing a higher percentage of water which does not ignite.

Drain the tank by removing the line at the petcock.  If you are unable to completely drain from there, remove tank and turn it upside down to get the remaining fluids out.  Refill with gas from a good source and see if that fixes it.