Intermittent whirring/whining sound.

[niclpnut]

I've noticed this on the 1100ES over the last week or so. It tends to come and go.

A few weeks ago I had a stator mount scew come loose. It ground half the head of the screw off and left a groove on the outside edge of the rotor:



I installed a new screw, buttoned everything up, and changed the oil as a precaution. However this rubbing/whirring/whining sound is still there.

It was kinda hard to identify the location of the sound when the screw came loose, but noticed a slight vibration from the stator cover when it happened. The sound now also is hard to track down...I've listened with an automotive stethescope but can't narrow it down.

Things I've checked...

Starter clutch gear only free spins clockwise and doesnt have really any play and will lock if turned opposite way so I'me assuming its good. Nothing else (bolts, rotor, stator, stator wire guides) on the left side were loose. Starter gear was correct with washer/gear/washer orientation.

Pulled the clutch cover, clutch hub/basket, and oil pump. Everything looks good with no abnormal movement wear.

Pulled the valve cover thinking tight valves, or cam wear (everything looked ok 200 miles ago). Nothing looked out of place/worn. Cam caps were torqued and tight, cam lobes looked good, rocker pads looked clean, valve lash was spec, and everything was coated with oil. Ape manual tensioner was still holding chain correctly with just a bit of slack and not too tight.

Plugs look good, with no fine bits of metal that indicate wear in teh cylinders.

I've never had it low on oil, and it's never overheated...and with about 2k on the clock since the rebuild, and 22k total on the bike, I wouldn't think I'd be having a problem in the bottom end.

Here is a small clip with the noise:

http://s1100.photobucket.com/albums/g418/niclpnut/?action=view&current=VIDEO0013.mp4

Nic

[tom203]

I assume you had a stator screw come loose( not a starter screw) and it got dragged around by rotor.So you likely got all screw debris out.Before the screw made it to the outside of the rotor, it had to get by the stator poles. Inspect the pole surface for gouging- maybe the stator mount to cover got bent slightly.

[hjfisk]

Sorry just see you posted the video, guess it's not the chain
Does this sound come and go all the time or just when you are moving? A chain will make some different noise's a tight spot. Just a thought

[earlfor]

Pull the left side cover and start the bike. If the sound is still there, its the starter clutch. If its gone, its the stator.

Earl

[Carter Turk]

I agree, I bet its the starter clutch bolts. Unfortunate since you were just in there replacing the stator screw.

[niclpnut]

Pulled the flywheel today, and everything looks great, bolts not broken and everything where it should be. Pulled the valve cover again just to double check, and everything is torqued correctly with a healthy coating of oil. Rockers and cam lobes look good. (could never really hear the noise as well up top but wanted to make sure.)

It's just strange that its intermittent. Getting a sinking feeling its a bearing going out.

Nic

[niclpnut]

Found this old post and the sound is similar however, my starter clutch appeared ok.

http://www.thegsresources.com/_forum/showthread.php?t=158608&highlight=bearing

Nic

[argonsagas]

There is also the possibility of a really simple problem having occurred when you had the cover off for the inside work, and it does sound possible that this applies here.

There is a small clamp that holds the wire leads to/from the stator and the clearance is VERY small. If it was disturbed to either left or right, or perhaps you added a washer, clearance is reduced and contact will result in noise which can be intermittent.

Repair is easy, as all you do is re-position the clamp and tighten it, or remove the new washer.

A second possibility relates to the same bolt (I have encountered both problems) and that is if you replaced the original bolt the new one just might have a thicker head than the original, and, because of the very limited clearance, the thicker head can make contact.

It will have to be removed and the top can then be ground down a bit.

This problem can be exasperating because the sound results due to the very tight clearance being compromised and as the engine heats/cools, or changes RPM, it makes the sound intermittent.

[niclpnut]

Yeah I thought so too.

I ran it with the stator cover off and the noise was still there.

I've checked everything short of pulling the cams and head again...

Guess I can check to see if the crank is somehow twisted and measure through the spark plug holes.

Nic

[OldVet66]

It's worth a check for peace of mind, but would result in timing issues. I doubt you have done that unless you have been pulling hole shots and slamming it into second.

[niclpnut]

Yeah, seems unlikely and shot bearing would be more knocking or metalic rattling.

Seems I read a twisted cramk can produce a whinning noise. Just one more thing to check off.

Nic

[niclpnut]

Without spark plugs bike turns over smoothly and quickly with no abnormal sounds.

Warm compression test:

150 140 142 155

Nic

[niclpnut]

Pulled the clutch out and ran it for about 10 sec. Noise still there.

[niclpnut]

Someone asked if I ever found out the cause of the noise.

Main crank roller bearing died. When I pulled the crank 2 rollers fell out...

Nic

[chuck hahn]

If you start it with the cover off oil will come gushing out the top big hole..I advise corking it BEFORE hitting the button.