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Discussion Starter #1
Hi all,

So as I'm riding more during the warm months I noticed I was getting a mild clack from the right side, so I adjusted the MCCT. I took up quite a bit of slack, so I did the left side too just to be thorough. On my test drive I was getting a whirring sound, sort of like a whooshing of air out of a semi-resonant pipe. I backed off on the tension on the MCCTs and that went away.

But now that I'm paying attention to noises I'm noticing that there's kind of an electric motor whine any time I'm riding around. Almost like there's an RC car speeding along under my wheels. I don't hear it at all when idling. Is this just the stator making noise? Is it normal?
 

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Discussion Starter #3
I haven't tried revving it in neutral, but I feel like it is more tied to engine speed than road speed.
I'll go for a ride this afternoon and see if I can duplicate stopped in neutral as well as whether or not it stops when the clutch is disengaged while moving.
I feel like it only happens when the drive train is loaded, either accelerating, maintaining speed, or decelerating, but I'll double-check. (guess that would rule out the stator)
 

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Discussion Starter #4
So I finally got back out on the road to try to figure this sound out again.

I re-adjusted the MCCTs on both sides (which didn't seem to change the final depth of the bolts) and revved the engine in neutral but didn't hear the sound.
On the road, the sound is definitely tied to rpms. It starts making a whirring noise around 2,500 and is audible through about 3,500 at which point I think it is still there but just gets drown out by the engine.
Pulling the clutch lever at speed does not change the sound.

Its one of those things where I wish there were someone close by who could just pop over and have a listen. Too bad.
 

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Something in the driveline? Rear gear, splines, bevel gear, trans, a bearing?

I've noticed all these bikes have some harmonics and a bit of gear whine. Hear it on mine and in some ride videos. It's usually around the speed you describe, maybe a bit higher, like cruising around 50 mph..
 

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Wear earplugs.

I don't worry about noises unless they are louder than the motor running. There's just SO MANY things that can make noise on a moving bike.

My FJR's windshield would whistle at certain speeds. My Bonneville has a squeeking sound I only here at slow speeds. My Vulcan was perhaps the noisiest bike I've owned.... The licence plate rattled, the gas cap squealed, the ACCT's would rattle a bit, but stop once warmed up.

Some I solved, some I just tune out now......
 

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So I finally got back out on the road to try to figure this sound out again.

On the road, the sound is definitely tied to rpms. It starts making a whirring noise around 2,500 and is audible through about 3,500 at which point I think it is still there but just gets drown out by the engine.
Pulling the clutch lever at speed does not change the sound.

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ok tied to rpm specifically, (test by riding at same speed in different gears), or vehicle speed.. you say pulling in clutch doesn't affect it, which would indicate vehicle speed.

if its tied to vehicle speed, check front/rear wheel bearings, lube in rear gear, and of course, splines. also check for anything rubbing/dragging (even in the rear brake assy)
 

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Discussion Starter #8
ok tied to rpm specifically, (test by riding at same speed in different gears), or vehicle speed.. you say pulling in clutch doesn't affect it, which would indicate vehicle speed.

if its tied to vehicle speed, check front/rear wheel bearings, lube in rear gear, and of course, splines. also check for anything rubbing/dragging (even in the rear brake assy)
I did a terrible job explaining that. I meant when I pull the clutch, I can change the road speed by breaking but tweak the throttle to keep the rpms in the 2.5-3.5 range and the sound remains, which rules out road speed.

Anyway, I'm going to try to ignore it for now. It'll be easier to track down if it gets louder!
 

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ok..

if its engine ONLY related, then sitting still with it in neutral (or clutch pulled in) and revving the engine will cause noise variations.. thats the easiest way to explain it.

otherwise, its drivetrain or other non-engine item
 

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In as far as only the whirring sound goes, mine sounds almost like a Triumph. It whirrs all the time. Always has. Actually it sounds kinda cool so I'm not concerned. I guess to a certain extent I'm like KM in the thought that the thing makes noise regardless. His remark about earplugs got me to chuckling because it reminded me of my dad. When driving his truck he would just turn up the radio so that he couldn't hear any particular suspicious sound. I'm not a mechanical hypochondriac. If I were the bike would never be ridden since at idle there's all sorts of sounds. Once moving it all seems to come together and all I can hear is the whirring and the exhaust. So far it has gotten me home each time with the same number of parts that it left home with.
 

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Don't overthink this. I know what you are hearing because mine did the same thing after adjusting mine. It's the sound of the chain on the chain guard after tightening the MCCT's. You can back them off 1/4 turn and it'll take a lot of the noise away. Done that on both bikes. It's just the way it sounds when the engine is so quiet that all you can hear is the chain passing over the guard when it's tight. Loosen it 1/4 turn and it'll be quieter. My engine was so loud before I did the MCCT's all i could hear is cling cling. Once I did them it got so quiet I nitpicked everything.
 
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