Fuel tank?

[KennonNC29]

my bike seems to have a massive reserve tank it'll do 150 ish km's then cut out when I restart it and get to a petrol station it'll only fill up with 8ish litres I should be switching to reserve but at filling it to brim with only 8 litres my reserve seems to be 7ish litres which must be wrong.

Kennon

[Neosophist]

The reserve should be 2 litres.

Perhaps you have a badly routed fuel line or a blocked tap filter or even an inline fuel filter.

I've come across all 3 causing this problem.

Is it always 8 litres? If it varies it could be a blocked breather vent causing fuel vaccum.

[KennonNC29]

its happened 3 times and always at 8 litres at around 150km done, when i switch to reserve to get to the petrol station its always that amount not sure why. Just find it odd, i'm having my bike worked on Saturday so the tank will be off will ask them to check the fuel lines for me,

Kennon

[Neosophist]

Yes.. check the above.

Fuel lines are routed the proper way.

The filter in the tank is clean (you can see it with a torch)

And if you have an inline filter. thsi can cause the issue too.

[KennonNC29]

cheers for the replies guys.

Kennon

[Cammo]

If it varies it could be a blocked breather vent causing fuel vaccum.

This could certainly be causing it (and is pretty common as these bikes get older and parts wear).

Easy way to check if it is this - next time the main tank is running out, pull over, turn the engine off and undo the fuel tank cap. If you hear any air rushing into the tank as you open the cap then you have a vacuum lock (faulty tank breather).


Remove any fuel line filters if there are any, not needed and can cause all sorts of problems.

[KennonNC29]

sorted now was just vacuum lock, did a nice 63mile run around the countryside of Oxford just perfect for the revvy VFR

Kennon