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Discussion Starter #1
Good morning everyone, and Happy Easter.

2001, just turned 20K miles yesterday. I just bought the bike, and did a TON on upgrades and maintenance on it. Here is my predicament...

I just noticed, at idle, I hear a knocking/rattling sound on the bottom of the bike. It goes away at any rpm above idle, or when the clutch lever is pulled in.

I am wondering if it is a clutch bearing, or a transmission input shaft bearing....

When I pulled the gearbox magnetic chip detector, it was very sludgy, and had metal shavings on it. I changed the oil with Royal Purple. I am going to check the chip detector again in about another hundred miles.

If there is anyone around that can help me diagnose, and/or have a tech day(s) to do the repair, that would be great. Also, I'm trying to figure out if is she grounded, or still rideable....

I'm not afraid to tear into anything, I would just prefer someone who might have done this before, and might have the special tooling.

Thanks!
 

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2011 R1200RT
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The LT engine is noisy, the injectors make a ticking sound, the alternator is also noisy when a load is applied (such as when I turn on my PIAAs and the bike is idling), so you may not have a problem, especially since the noises go away with RPMs.
Finding fuzz on the transmission drain plug is also normal, as long as you are not talking metal chunks. At only 20k miles your engine/transmission are still fairly new.
How were the fluids when you drained the engine and tranny?
 

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Discussion Starter #3
The oils were not bad. I may not have a problem, I just don't remember my other K12s being this noisy. It runs smooth as glass and shifts flawlessly up and down.
I am guessing this was the first transmission service....just a hunch.
There were some very small shavings on the chip detector, but nothing large enough to get a part number off of..... :D
 

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Agree with the above It could be so many things. Not hearing the noise its impossible to tell. Some loose plastic body part etc. I had a noise that went away after it warmed up that only my dealer tech found during a test ride. It was a crack in the exhaust. Fixed that with a weld. And the plastic body part was fixed with double sided tape. I think my fender rattles on idle too.
 

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Discussion Starter #5
mwnahas said:
Agree with the above It could be so many things. Not hearing the noise its impossible to tell. Some loose plastic body part etc. I had a noise that went away after it warmed up that only my dealer tech found during a test ride. It was a crack in the exhaust. Fixed that with a weld. And the plastic body part was fixed with double sided tape. I think my fender rattles on idle too.
I stripped her again last night.....still noisy... An exhaust crack was my first thought, by pulling the clutch lever silences it.....
 

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Cochinosucio said:
I stripped her again last nigt.....still noisy... An exhaust crack was my first thought, by pulling the clutch lever silences it.....
Just for grins, now that you have some of the tuppeware off - throw a socket on a torque wrench extension and check the tightness of each of the eight exhaust to header flange bolts.
 

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Discussion Starter #7
Dick said:
Just for grins, now that you have some of the tuppeware off - throw a socket on a torque wrench extension and check the tightness of each of the eight exhaust to header flange bolts.
Dick, you always have great advice! :bowdown:
 

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Did that fix it ?

If not then maybe a Mechanics Stethescope would help you isolate the exact thing that's knocking... The LT's engine is really noisy...Most of the noises you hear are normal...

Kind of freaky when you hear a particular noise and then you fixate on it till you realize it was probably there all along with all of the other noises you're going to fixate on at a later time.......

I hope it's nothing major. The Alternator can be really noisy at idle...Normal......

John
 

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Come on over and we will have a tech day, even if only for your bike and mine.

Have ife, and many tools, some of which I even might now how to use!
 

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It's probably gear lash in the alternator. This will quiet itself when the clutch lever is pulled. It also quiets itself above idle. Mine's been doing it for 40,000 miles.
 

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Discussion Starter #11
deanwoolsey said:
It's probably gear lash in the alternator. This will quiet itself when the clutch lever is pulled. It also quiets itself above idle. Mine's been doing it for 40,000 miles.
Thanks JPSPEN, AND DEAN!
The culprit was the alternator! Any load increased the noise, loads off..... quiet as a mouse fart. What a relief!
Thanks fellas!
 
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