What's that Ka-Ka-Ka-Ka Noise on Deceleration?
 

Hoping you geniuses and semi-geniuses can help me diagnose this one.

Bike: 2000 R1100S (Mandarin, if it matters), with just under 24,000 miles.

Noise happens when decelerating so a stop (e.g., coming to a stop at a stoplight). Sounds like a "ka ka ka ka ka ka ka ka ka" sound, decreasing in frequency as the engine decelerates. I can make the sound more prominent by pulling the clutch in and coasting to a stop, but even with the driveshaft engaged (i.e., clutch not pulled in), the sound occurs. Sound is not present when the bike is revving or running steady at rpm. It's only a deceleration sound.

My guess is that what's happening is the flywheel is shedding excess momentum into one or more of the cam chain/s, and my cam chain tensioner (or one of 'em) needs adjustment. Plausible theory? Anyone else experience something similar?

TIA,

Dana in Philly

It might be just calling you names. Or some ka ka like that.
Other than that, it's anyones guess without hearing it. :)

Timing chain tensioner begging for attention.

It would make that noise at idle as well.

It was either that or playing cards in the spokes; but, it's not a GS.:D

Does the pace of the noise slow down with the speed of the bike?
If it does when the clutch is pulled in, it's rotational in the wheels/bearings/brakes, etc.

If I decelerate to a stop, and am idling, it's often there, and a little throttle blip will make it go away.

I'm still liking timing/cam chain tensioner. Bike's the right age to need the adjustment, methinks.

I only noticed this because I'd been wearing an open faced helmet this week on some lazy rides to work.

Or driveshaft? IOW, anything back of the clutch.

Well then adjust the cam chain tensioner and see what happens. It's not difficult as I recall....been awhile.

PS edit. I don't have ready access to the shop manual but isn't the chain adjusted by oil pressure? I used to hear it sometimes on start up and then it'd go away after a few seconds. So I'd check that.

Timing chain slapping.:)

But the noise is still there *after* I've come to a stop, as the engine slows down to idle. So I don't think it's in the wheels/brakes etc.

Thanks all for the help. Great resource.

You don't normally hear it with a full face helmet. I heard mine with a flip-up.

Unless the cam chain tensioner is broken, they usually quit making a racket once the oil pressure builds up.
Happens with or without the clutch pulled in, sound decreases as speed decreases...
My money is on the driveshaft.

Acchhh, now there's a lovely thought. Hope not. I guess I'll:

1. Top up the oil to mid-sightglass (although in my experience that's always too much for a beemer). See if the noise goes away.

2. If not, check the tensioner, adjust if needed. See if the noise goes away.

3. If not, investigate further....

Checked your alternator belt lately?

Usually comes from low oil pressure, the cam chains slack when the tensioners don't get enough pressure to hold the charge. More oil should make it disappear.

I don't think they can be adjusted and I don't think you can just add oil to make the sound disappear. The old style are a three part, tube, spring, bolt. Typically the right tensioner is the one that gives problems. It's the one on top of the cylinder and will leak down. That's what causes the "clanging" sound, until the oil pressure builds back. I replaced both of mine with the newer version and I don't hear that "clanging" sound anymore.

If you keep the oil level within the circle it should be fine. I doubt that a tiny bit low oil will make any difference in the symptoms you describe. The low oil and loose chain thing is a start-up phenomenon....goes away within 20 seconds.

Is Bill the cat hiding in your fairing?

YouTube - Opus - Hairball

Mine does that sometimes on rough pavement coming into a tight corner and decelerating hard.... Wheel hop.... A little bit of throttle usually smoothes it out and gives a nice slide... Perhaps a slipper clutch would be a good investment if you are backing it in that much.













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Jduke, you are probably right that the original tensioners design has a defect that make this happen, and changing them for a new design would solve it. But the problem appearance is closely related to oil pressure. When I switched to synthetic oil I experienced crazy oil consumption. Following the advices of this valuable board, I tried keeping the oil level in the bottom quarter of the window, and suddenly at every hard braking it would happen. For this only reason I keep the oil level close to the max at all time (anyway oil consumption is back to normal now), and it made it disappear instantly. Actually, I now take advantage of this noise as an indicator of the oil level, as it usually appears exactly when reaching the bottom of the window :D

Keeping the engine at revs over 3k also helps. I don't know exactly the reason, possibly the oil pump is activated by the engine and at low rev it does not pump enough to keep the tensioners happy.

It is the left side (sitting on the bike) one that is replaced with the new style adjuster.

+1. I recently changed my alternator belt and rode the bike briefly without the cover on to see how the tension changed after the engine warmed and noticed quite a clacking when decelerating. The noise is still there, but the cover covers it up.

Unless I missed it, you haven't told us from which end or side the sound is emanating.

-Jeff

Alternator belt was checked at service this February. It's OK.

Yesterday afternoon, after letting the bike sit on the sidestand while it cooled down, with the bike on the centerstand, I added oil to the center dot of the sightglass.

This morning, wearing an open-faced helmet again, no ka ka ka ka noise on deceleration anymore. So, that was it: low oil level and resulting timing chain tensioner noise.

As Frank Cooper used to say, "It's a feature, not a flaw!" We've got an audible "I want more oil please" signal.

Thanks to the hive mind here for the diagnostic assistance. You guys rock. And I'm sorry to have started a semi-oil thread. ;)

I run my oil/hexheads on the center dot. What a cheap fix that was.:D

That's a classic cam chain noise. I don't want to jinx you, but I don't think you fixed it. It will come back under the right (wrong?) circumstances, generally a high rpm roll-off without squeezing the clutch with a warm engine. It will also happen occasionally on start-up.

The fix is to get an updated cam chain tensioner. The best thread on the process is over at Advrider in the GSpot section. Make sure you read the whole thing. The part numbers changed about halfway through the thread. You want to make sure you get the right parts. They're cheaper, simpler, and better, a rare combination if there ever was one.

As a note, driveshaft problems are easy to diagnose. If you spin the rear wheel by hand, there will be a distinct "clunk-clunk" if your u-joints are going bad. You don't get much warning before they grenade, so if you ever feel that, park the bike and start looking for a used driveshaft.

Sounds like a good idea for the next service interval. Get that update.

The odd thing about the R1100S -- compared to, say, the original flying brick K-bikes --- is that it's rather ridiculously involved to actually know if your oil is at center dot. Stop the bike. Lean it right for a 10-count to let the left jug drain, then put it on the sidestand to cool, the onto the centerstand. Wait awhile and check the sightglass.

But OK, I'm down with that I guess. All part of the fun.

Jerry Duke posted awhile back that he comes in an put's the bike on the side-stand and goes to take off the riding gear and grab a cold beer. When he gets back he puts the bike on the center-stand and checks the oil, beer-in-hand. If Jerry didn't say it then maybe Bob Hancock did (except, his BCP didn't have a center stand). :)

Correct Bubba. I've seen others post the procedure and know it gives the most consistent reading.
The bike has to have been riden for about 30 miles (operating temp so the oil cooler thermostat is open), park the bike on the side stand for 10 minutes (allows oil to drain from oil cooler), put bike on centerstand for 30 minutes (allows all oil to drain from oil passages).

I don't know if a dealer will do it for you. I think those are actually R1200 parts. It's pretty easy though.

And yeah, R bikes are a much more "hands-on" experience than K bikes.

I have done the oil level check routine with mine then come back in the morning to find less oil then when it was hot the night before. As if it sucks some back up into a cavity.

I just replaced the tensioner this weekend. A huge improvement. No more noise at start up. The article in ADVRider makes the job harder than neccessary. You do not need to disconnect everything on the fuel injector. Just loosen the clamps, remove the screws going into the air box and pull everything out of the way. Total time for me was about 45 minutes. 10 minutes of actual work, and 35 minutes of looking at it and wondering why I wasn't having any problems. (I am mechanically challanged). I bought it as a kit from Ted Porter BMW for $85. Well worth the money.

Ted's kit have instructions? Or did you use the ADVrider instructions?