HELP: Buzzing sound blow fuel tank when ignition is on! Could it be the FPR?

[TheJackal]

Hey Guys,

I've just come back to my 929 after a 2 week holiday, charged up the battery with my usual battery charger but found something a bit odd...

When I switch the ignition on (via the kill switch) and the injection has primed up, I can hear a sort of loud buzzing noise beneath the fuel tank...kind of like the sound an electrical transformer makes.

The bike starts up and seems to run fine but if I repeat the process again, the buzzing sound is still there. I haven't dared go out on a ride yet because I'm kind of afraid it will die half way back home!

Could it be the fuel pressure regulator or the fuel pump dying on me?

[TonyB]

Sounds like the servo motor for the exhaust valve. I would remove the exhaust valve and check it is free to move before it chews up the teeth in the servo motor. Hopefully it will not have done so already.

[bladeracer]

Originally Posted by TheJackal Hey Guys, I've just come back to my 929 after a 2 week holiday, charged up the battery with my usual battery charger but found something a bit odd... When I switch the ignition on (via the kill switch) and the injection has primed up, I can hear a sort of loud buzzing noise beneath the fuel tank...kind of like the sound an electrical transformer makes. The bike starts up and seems to run fine but if I repeat the process again, the buzzing sound is still there. I haven't dared go out on a ride yet because I'm kind of afraid it will die half way back home! Could it be the fuel pressure regulator or the fuel pump dying on me?

Sounds like the servo motor is stripped. Any error codes?

[TheJackal]

Thanks for the fast replies

Thing is I've got a full Akro on the bike and also the flapper valve has been removed!

I had the exhaust fitted about three weeks ago by the Honda dealer and they didn't keep it in the correct position so I've had the annoying FI light on ever since.

Can I disconnect the servo motor and run the bike like that? I'm not fussed with the FI light....as things are going I might just keep the bike for the track and not even run it on the road.

[bladeracer]

Originally Posted by TheJackal Thanks for the fast replies Thing is I've got a full Akro on the bike and also the flapper valve has been removed! I had the exhaust fitted about three weeks ago by the Honda dealer and they didn't keep it in the correct position so I've had the annoying FI light on ever since. Can I disconnect the servo motor and run the bike like that? I'm not fussed with the FI light....as things are going I might just keep the bike for the track and not even run it on the road.

Unplug the servo motor and remove it.
If you still hear the noise then check the fuel pressure regulator as the pump may be pumping fuel straight into the engine via the vacuum hose.

[TheJackal]

Will do, thanks.

I rotated the servo round a bit and repeated the whole process, buzzing sound went away so it definitely points to the servo being the source.

One less thing on my bike then!