Newbie with a problem

[spinningman]

First off hello to you all - I am new here having had my 600 Divvy since Oct last year.

I have recently noticed that the bike is making a weird noise (best desctiption would be a drone) over about 30 mph in any gear. The noise only occurs when i have some (any) throttle on - If I close the throttle then the noise goes. The drone seems to speed up as speed increases (until i can't hear it anymore due to wind noise but I assume its still there

I have checked/tried the following :

Chain tension - it was a bit tight (cos I adjusted it on the centre stand the first time) but i have now re-adjusted with the bike loaded and its fine

back Brakes - the noise is still there whether the brake is on or not

Oil/filter - changed (used mf spec oil)

Chain lubrication - fully degreased the whole chain/sprockets etc and re-lubed using Castrol chain wax

I am out of ideas now and wondered if anyone had experienced a similar issue on their bikes and could help me at all.

any help appreciated

Cheers

[CD]

Some ideas:
Disc pads binding. My HH fronts make a noise when used but are quiet otherwise. If they were dragging they'd buzz constantly.
Worn chain. It should not be possible to pull a link away from the rear sprocket.
Rattle in fairing. They all do this (most annoying) you'll have to stuff rags or bits of kitchen towel into various places until it stops.
Helmet has a fly wedged into an air vent.

[darren]

wheel bearing perhaps or dry speedo drive

[spinningman]

Thanks for the comments - I checked the wheel bearing by putting the bike on the centre stand and checking for play side to side and top to bottom - nothing

Is the speedo drive an easy thing to check or is it a replace and see if it stops?

The fairing noise is a different one to the one I'm hearing - I though wheel bearing when it first started but thought it was strange that a bearing would only make a noise when the throttle is on (no noise at all if I back off or pull the clutch).

Is it possible to over tighten the rear wheel and could this cause the noise? - I didn't torque the axle nut just gave it a bit of welly with a socket (I know its wrong)

Thanks again for the advice

[amorti]

Rear sprocket bearing. Try wobbling the rear sprocket side to side - if it wobbles, it's broken badly. If it doesn't, you still can't eliminate it til you remove the rear wheel, clean that area all up, and turn it with your fingers. That's explain why it only does it with throttle on, too. Mine was completely disintegrated, and you couldn't tell until it got that bad that shards came out on to the chain, well not without taking the wheel out. I wash the bike weekly and wobble all bearings while doing it, that's a new one added to the list.

Noticed any clunking when pulling away? That's another sign.

It's possible to overtighten the rear wheel, but all you'd do is tighten spacer against bearing against spacer, etc. Wouldn't affect the bearings until you pulled it so tight the bearing inner races distorted. You'll probably strip the thread or crack the nut open first. (pretty certain)

[joriff]

I'm sure its the fairing vibrating, mine does that!

[neilmud Lord Protector]

Think simple if the noise is only when throttle is open and goes when freewheeling with clutch in it is not likely to be running gear probably noise from the carbs/air box something loose vibrating or normal induction noise.

Neil

[amorti]

With no stress on it, the sprocket bearing is held level by the cush rubbers. Accelerating puts sideways stress on it, so it'd get noisy.

Easy thing to eliminate, just have the back wheel off. Could probably use a clean anyway.