Whistling noise at highway speeds

[Overkill777]

I've noticed a high pitch noise when riding on the highway on my 94 vs800. To me it sounds like a whistling noise but it could be something else, it's high pitch. Pretty faint and hard to hear over the wind noise.

It only happens when the engine it under load. If I pull in the clutch and coast it stops immediately. I can't hear it at low speeds or with the bike parked in neutral and revving.

Just wondering if this could be a problem. It runs fine.

I though maybe it's sucking air so I made sure the rubber boots between the carbs and engine are tight and secure but that didn't make a difference.

[Overkill777]

I think the noise may actually be the fuel pump.

[hillsy]

The fuel pump would also make that noise at high RPM but you are saying it is just when the bike is under load?

Could possibly be a leak where the crankcase breather pipe goes to the airbox? Or some other leak at the airbox? The pressure in the airbox would change more under load than anywhere else.

[Overkill777]

Yeah just when under load. I only hear the noise when at 70-75 mph. It's pretty faint over thst speed it may just be wind noise drowning it out. I benched tested the fuel pump and that's not it.

I agree with you it seems like it's sucking air somewhere around the air box.

[Overkill777]

I'm actually starting to think maybe it's gear whine or something. I suck at this.....