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Discussion Starter #1
Since about a month I have been hearing a random sounds from the engine/transmission.

It felt like the piston is hitting the head (heard this couple of times). The noise lasts for less than 10 seconds and went away. I was taking a slow left turn at a signal about a minute after starting the bike. The engine was still not yet at operating temperature.

Today morning when I started the bike cold on the side stand and then straightened the bike there was a churning sound that felt like metal rotating against metal. But the bike is stationary and the clutch is not even engaged and the bike is in Neutral. Again this was when the bike was cold.

There has been no performance change, clutch does not slip in 5th gear, engine breaking is very strong, no reduction in power, oil and oil filters are new in engine transmission and fd. Air and Fuel filters were changed at 12K miles ago (bike had 30K miles then now it has 42K) and the valves were checked at the same time.

The transmission oil was changed first time at 20K miles and had a lot of metal on the magnet. Second oil change had very clear oil at 30K miles. I performed another transmission oil change at 40K and had some metal flakes on the magnet.

Since this is random sound and lasts for less than 10 seconds its difficult to identify the source. What should I be checking to ensure I am not stuck on the road someday?

Amish.
 

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on your description I would guess engine pinging, (pre-iginition) I would guess you were lugging the engine around the corner, and you are also using low octane fuel.
 

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Discussion Starter #3
Probably true. I do drive in higher gears many times. Low octane fuel is also a possibility since I used the 87 octane once recently since the gas station was out of premium.

Above explaination is possible for the slow speed left turn. How about engine/transmission noise when its idling? Can the engine with low octane fuel make grinding metal plate noise? Or I need to worry about the transmission?
 

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Axle said:
on your description I would guess engine pinging, (pre-iginition) I would guess you were lugging the engine around the corner, and you are also using low octane fuel.
+1. :thumb:

Rev it, anything under 3K is not good. This is a HIGH rpm engine - do not be afraid to cruise at 60 mph in 4th gear! You will not hurt it by riding as a sport bike, the brick can kick butt and is STILL one of the best engines every invented by anyone, anywhere in the world. It is SOLID...

(and doesn't puke water pumps like the K1600's.) :D

Ride it all the time like you are doing an "Italian" tune up and you will be amazed how rewarding it is... :dance:
 

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2005 K1200LT
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Any time the rpm drops below 1K you can hear some growling in the drive train gears(crank to alternator drive to output shaft) that can be a bit unnerving.
 

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Discussion Starter #6
Sound kept getting worse and today I have a jammed rear wheel. Fortunately I managed to reach home. Here is a video of the sound. It appears from the final drive. Is there anything in final drive thats moving while the bike is in neutral?

https://www.youtube.com/watch?v=i8YIkQwCfFY

The sound is audible the most between 35 sec to 45 sec of the video. Also the fluid on the ground is from my attempt at bleeding the brakes. But i have also tried to capture some leaking oil from final drive that i observe today for the first time.
 

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LTFan said:
Sound kept getting worse and today I have a jammed rear wheel. Fortunately I managed to reach home. Here is a video of the sound. It appears from the final drive. Is there anything in final drive thats moving while the bike is in neutral?

https://www.youtube.com/watch?v=i8YIkQwCfFY

The sound is audible the most between 35 sec to 45 sec of the video. Also the fluid on the ground is from my attempt at bleeding the brakes. But i have also tried to capture some leaking oil from final drive that i observe today for the first time.
If the rear wheel is not moving, nothing in the Final Drive is moving either.
 

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I am going to throw my hat into this one, have you checked the disc of the brake for the cowbell effect? It could be that the bike is getting just the perfect resonance at idle that the disc is cowbelling (did I just make that word up?).

Second, check your heat shields and exhaust system, whack it a few times and places (not too hard) with a rubber mallet to make sure it is not rattling.
 

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Discussion Starter #9
The rear disc seems to be holding pretty strong and it doesn't appear to be causing this sound. But it was hot yesterday night when I reached home. I compared it to the front discs and the rear was considerably hotter than the front ones.

This sound started late last month and has been increasing steadily. I have heard this sound only when I start the bike, I have practically not heard a sound while riding or after the ride. I changed the final drive 2 weeks ago and the old oil looked pretty clean. My transmission oil generally has sparkles of metal in it few times.

I will drain the final drive oil again tonight and check for flakes/metal in there.

Amish.
 

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with the bike on the center stand, with engine running, transmission in any gear clutch pulled in (disengaged) wheel not moving do you still hear the noise?
 

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That's the cowbell... Just getting started..Trust me.. That IS the cowbell...And it will, Over time, Get way louder than that...

The rotor is a floating type. A big steel ring set over the center piece and held together by those Stainless Crimp Rings.... And that slight movement causes it to sing....Like a cowbell..Reach in there and grab it and the singing will stop...

Nothing wrong with that.. It's normal...Even though you might not be able to move it much by hand.. There's enough play in there to let it sing...

If you take the rotor off and properly re-crimp the retainers. It will stop.. Till they loosen back up again.
But that's not going to be practical for someone without the proper equipment..

I've heard of smearing a wedge of RTV around each of the crimp rings.Both sides.You'll need to take the wheel off. After it solidifies. The sound should be gone... The RTV still allows the rotor to float. But damps it enough to stop the sound..

My only worry about doing that might be if you got the rotor hot enought to cause the RTV to burn...I don't know if that's a stretch or not..

The Jammed rear wheel is another story.. You probably need to bleed the brakes..And you could have a sticking caliper causing the brakes to drag and heat up the rotor..The brakes drag, Which heats up the Rotor, Which heats up the caliper and the fluid expands and causes the brakes to drag even more... Pretty soon the whole mess will burn up..

John
 

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If it is cowbell syndrome I have a ghetto fix for that (well, actually it is my father's ghetto fix - he is the king of the ghetto fix). My R1200C was cowbelling so he cut chunks of rubber off an old hose and stuffed them between the hub and the little prongs that stick out by the rivets. Occasionally I will still hear a bell if I hit a substantial bump in the road, but the normal ding-a-linging is gone. I have to peak under the LT saddlebag to check, but I think it is basically the same setup on my LT as my C, but I could be wrong.
 

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I just modified my rear disc by cleaning it up good and then running a bead of Scotch 800 sealant around the scalloped edge of the disc. Once that dried I applied Loctite bearing mount (the red stuff) to the opposite side. The capillary action pulled it into all the rivets and damper rings. Into the oven at 180 degrees for a couple hours after that. I think it's fixed but I'll know later this week. It's probably worth mentioning that mine was not loose enough yet to clang.
 

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Discussion Starter #15 (Edited)
Thanks everyone for the inputs. There is no oil light on the dashboard.

However the oil (or something that used to be oil) In final drive is burnt, missing and extremely smelly. Very little oil was received when i tried remove it from the fd. Pictures attached.

A video with my best skills at shooting in dark.
https://www.youtube.com/watch?v=JbpR9rw2rdU

What's the recommendation? Should i get a used fd or get help to fix it. I imagine if its fixed by an experienced person then it will not spoil again soon. But if i get a used fd then its only waiting to fail again.

Amish.
 

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LTFan said:
...
However the oil (or something that used to be oil) In final drive is burnt, missing and extremely smelly. Very little oil was received when i tried remove it from the fd. Pictures attached.

What's the recommendation? Should i get a used fd or get help to fix it. I imagine if its fixed by an experienced person then it will not spoil again soon. But if i get a used fd then its only waiting to fail again....
Amish,
from what I can see, the FD lube doesn't look that bad. The metal on the drain plug magnet, from what I can see of it, does not suggest a crownwheel bearing failure.

The lube is dark and may have been a little low. Petroleum based gear lube is pretty smelly if you're not used to smelling it.

I'm not experienced with the "cow bell" brake rotor, but when I listened to your first video, that's what I thought it might be; other board members are more confident that the noise is the brake rotor; they are probably correct.

I suspect all you have is old lube that was a little low and needed changing. I would not be paranoid about a FD failure at this point. My suggestion for the final drive is to fill it with fresh lube (just fill to the bottom of the threads of the filler hole (do not spin the rear wheel while filling or you will over fill, it doesn't take much). After another 500-1000 miles change the lube again for another check.
 

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Amish - you may have already checked the exhaust header flange bolts for the correct tightening torque, but just in case you haven't, you might check 'em. They'll make a hard-to-locate noise if they've become loose.

You'll need to remove the left side 'lower' fairing, and using a torque wrench and socket extension, make sure each flange bolt is torqued to 22Nm. This may not at all be part of your noise/sound problem, butt it is a good idea to occasionally check those bolts. Good luck with getting all the issues resolved. Betcha with the help here, and maybe help from someone in the Sac area, you'll git-r-done.
 

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Discussion Starter #18
From here it looks like a weekend activity for me. I will start by checking the exhaust, engine clutch in sound test and break rotor. This is for the noise. But what about jammed wheel? The oil in FD is 1500 miles old and it was mobile 1 synthetic. There is also oil leak under the final drive between the FD and the rotor. I now believe i am looking at multiple issues.

If the members don't mind my messy garage i could host a tech day on Saturday.
 

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LTFan said:
From here it looks like a weekend activity for me. I will start by checking the exhaust, engine clutch in sound test and break rotor. This is for the noise. But what about jammed wheel? The oil in FD is 1500 miles old and it was mobile 1 synthetic. There is also oil leak under the final drive between the FD and the rotor. I now believe i am looking at multiple issues.

If the members don't mind my messy garage i could host a tech day on Saturday.
What is jammed? What is it that makes you say it is jammed. Does the rear wheel turn? I read in one of your posts above that the wheel was jammed but you were able to ride home.

If you have oil that dark after only 1500 miles, no significant metal in the lube, a leak at the hub seal behind the brake rotor, my first guess that the tapered roller bearing is spinning.
(I retract my earlier statement suggesting that you change to lube and ride it.)

A spun tapered roller bearing will cause the lube to turn dark due to suspended aluminum particles which of course don't accumulate on the drain plug magnet. Additionally, the slight wobble induced by the tapered roller bearing shaft wear will cause a lube leak at the hub seal.

The only way to tell for sure is to open the final drive for inspection.
 

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If you still have the drain plug with the goop attached, set it in a cup and fill the cup with mineral spirits. Let it set overnight and then take a look at it. Any large ferrous fragments will be visible as the oil will dissolve and fall away. Could be a seal issue as well. Synthetic lubes turn black when exposed to water. Standard oil turns a cream or tan color from water contamination.
 
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