Author Topic: Rattling sound that I can't pinpoint. (fixed)  (Read 4878 times)

Offline Deepnoizer

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Rattling sound that I can't pinpoint. (fixed)
« on: July 28, 2020, 12:00:59 PM »
k1100lt 93 (or whatever is left of it)
I have rattling sound I can't pinpoint precisely and the general location indicates is not a fun place to tear into, so I would appreciate any guidance where to start.
The problem started roughly this spring after I replaced leaky radiator.
I don't feel like there is any performance issue associated with the issue and bike does not cook or anything unusual.
Increasing RPS and speed does not appear to effect in a noticeable way.

here is the short video showing it quite well:



It appears to come from are on oil pan behind the water pump but I can't be sure.
Don't believe its the famous monkey nuts since I replaced them recently.

Any help appreciated.

Thx




  • NYC
  • K1100

Offline Scott_

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Re: Rattling sound that I can't pinpoint.
« Reply #1 on: July 28, 2020, 04:17:34 PM »
Don't want to state the obvious, but are you sure you have all of the exhaust header bolts tight at the head connections.
I hear, what sounds to me like, a light metalic rattle as if something is not tight, almost too crisp to be coming from inside the intermediate housing gear assy.
It seems to get louder as you move to the front than the right rear(maybe the exhaust is drowning it out). You didn't pan over to the left side of the bike......
  • My Garage
1997 K1100LT 0302488 (resurrected)
2017 FLHTK Ultra Limited
1995 K1100LT 0302044 (R.I.P.)
1997 R1100RT ZC62149(sold)
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Offline Laitch

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Re: Rattling sound that I can't pinpoint.
« Reply #2 on: July 28, 2020, 05:02:18 PM »
Increasing RPS and speed does not appear to effect in a noticeable way.
The noise doesn't increase in speed with increased rpm?
  • Along the Ridley in Vermont.
  • 1995 K75 102,000 miles

Offline Deepnoizer

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Re: Rattling sound that I can't pinpoint.
« Reply #3 on: July 28, 2020, 06:08:26 PM »
Don't want to state the obvious, but are you sure you have all of the exhaust header bolts tight at the head connections.
I hear, what sounds to me like, a light metalic rattle as if something is not tight, almost too crisp to be coming from inside the intermediate housing gear assy.
It seems to get louder as you move to the front than the right rear(maybe the exhaust is drowning it out). You didn't pan over to the left side of the bike......

Was thinking the same but I can't see anything loose. I have been considering firing it up without exhaust at all to see, might just do that.
It is for sure louder front but it drops down in are of water pump, feels very much like 2/3 of engine going from the back.
  • NYC
  • K1100

Offline Deepnoizer

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Re: Rattling sound that I can't pinpoint.
« Reply #4 on: July 28, 2020, 06:11:01 PM »
The noise doesn't increase in speed with increased rpm?
I don't believe it does. Tried increasing RPM shaking, leaning ... nothing I do stationary effects it.
At speed its hard to tell but does not sound like it i getting worse, not in a way where I could pick it by ear alone.
I have external microphone on action camera, might give it a try.
  • NYC
  • K1100

Offline blackie1

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Re: Rattling sound that I can't pinpoint.
« Reply #5 on: July 29, 2020, 03:23:49 AM »
it is a simple calculation Laitch.
rpm x 60= rps
 112350
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Offline Laitch

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Re: Rattling sound that I can't pinpoint.
« Reply #6 on: July 29, 2020, 08:35:16 AM »
rpm x 60= rps
I'm putting that discovery on my calendar.  icon_cheers

Anyway, these tinny noises are often found coming from heat shields or other loose parts. From here in the woods though, it sounds like a ticking lifter but I don't think you've gone that far in modification.  :laughing4-giggles: Follow this rider's odyssey and decide if you want to launch the ship.
  • Along the Ridley in Vermont.
  • 1995 K75 102,000 miles

Offline Deepnoizer

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Re: Rattling sound that I can't pinpoint.
« Reply #7 on: July 29, 2020, 08:58:44 AM »
Started to do once over of all bolt and loose parts I could find.

Noticed on one of the header pipes a bit of oil below the engine ... this can't be sealed properly.
Started checking torque on all bolts and noticed quite few of them were not tight enough.
Quite sure now, one of the rings holding headers was ringing, even thou I could not feel any movement touching it.

Sound is gone now !
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Offline Laitch

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Re: Rattling sound that I can't pinpoint. (fixed)
« Reply #8 on: July 29, 2020, 09:09:51 AM »
Don't want to state the obvious, but are you sure you have all of the exhaust header bolts tight at the head connections.
Quite sure now, one of the rings holding headers was ringing, even thou I could not feel any movement touching it.

Sound is gone now !
icon_cheers
  • Along the Ridley in Vermont.
  • 1995 K75 102,000 miles

Offline Scott_

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Re: Rattling sound that I can't pinpoint. (fixed)
« Reply #9 on: July 29, 2020, 03:57:47 PM »
 112350
  • My Garage
1997 K1100LT 0302488 (resurrected)
2017 FLHTK Ultra Limited
1995 K1100LT 0302044 (R.I.P.)
1997 R1100RT ZC62149(sold)
"One who does not ask questions is ashamed to learn" Danish proverb

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