Recently bought an '04 with 2500 miles. Looking to do some exhaust and maybe a couple of other things to it. Trying to make sure it's tip-top before I start tinkering. I have this weird sound when I turn on the ignition/RUN position. It doesn't happen every time but almost always when totally cold. Searched and haven't been able to ever find any mention of it here or on youtube.
What is this weird A** sound?
- Thread starter klutch14u
- Start date
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Sounds like the fuel pump and the VBoost cycling to me. I cannot hear anything else.
Fuel pump: pop-pop-pop-pop-pop---pop---pop (It slows down as fuel fills the float bowls, and the float valves shut-off flow)
VBoost: a steady, short r-r-r-R-R-R-r-r you can watch the cable for the VBoost actuation move the two butterflies below the carburetors open, then closed. The butterflies are of-course inside the manifold, you cannot see those cycle open/closed, but you can see the cable and linkage go under tension (VBoost butterflies open), and then relax (VBoost butterflies close)
Fuel pump: pop-pop-pop-pop-pop---pop---pop (It slows down as fuel fills the float bowls, and the float valves shut-off flow)
VBoost: a steady, short r-r-r-R-R-R-r-r you can watch the cable for the VBoost actuation move the two butterflies below the carburetors open, then closed. The butterflies are of-course inside the manifold, you cannot see those cycle open/closed, but you can see the cable and linkage go under tension (VBoost butterflies open), and then relax (VBoost butterflies close)
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Ok, great. The fuel pump was my hope but wasn't sure it should sound like that. I've watched countless videos on the vmax lately and haven't seen any that had that sound in the video. Maybe their bikes were already warm/primed.? I'm definitely familiar with the vboost sound although this sound drowns it out when it occurs.
