whirring noise

[mkr]

whirring noise when i close the throttle, disappears when pull clutch in, clutch working fine, nice noise, like turbo winding down, noise shouldn,t be there though, bike done 50000mls, any ideas,? plan at moment is to ignore and keep fingers crossed.

[garynortheast]

Does it make the noise in neutral or just in gear?

[mkr]

different speeds but typical example would be, doing fifty mph, close throttle as if to slow down, noise appears, pull in clutch, noise disappears, let clutch out noise will reappear, any gear, any moderate speed or high speed, accelerate and noise disappears. open throttle no noise, close throttle noise. nice noise but shouldnt be there.

[mkr]

ps, no noise in neutral stationary, havent tried neutral at fifty!

[garynortheast]

What you describe would point to the gearbox.

[admin]

Might be the gearbox but the gears would still be spinning with the clutch pulled in as they would be driven my the rear wheel. I'm wondering if it's coming from the intake as the noise appears when the throttle is closed creating high air pressure.

[Bibio]

Could be too tight a chain.

[mkr]

dont want it to be gearbox, although i was thinking the same. not going to touch gearbox, so will be fingers crossed ploy.

[mkr]

dont think airbox, though i think it might be gearbox like gary north east says, i also thought like you all gears and bearing would still be turning so the noise should stay with clutch pulled in, but could be gearbox under load and then not under load

[mkr]

dont think chain too tight, but could be worn chain perhaps, might take a deeper look at chain and sprockets