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Hi all .Ive just bought a 99 K1200LT with 26,000 miles on the clock its in fantastic condition and im over the moon with it . I purchased her when my old Triumph Trophy let me down in Scotland on holiday when I was 400 mile from home and just decided on the spur of the moment to change it. I have to say its fantastic to ride and I haven't experienced comfort like it! The only little problem ive noticed is when I first pull away in first I get a harsh Knock Knock not every time and doesn't seem to do it after the very first take off . But leave it a while and pull away again it will do it once again ? Does anyone know how to cure it or know what it might be ?
many Thanks Edge
 

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more than likely normal k rattle, pinging is more of a rattle like shaking a paint spray can. some seem to be louder than others. While hot idling, apply the brakes that should re produce the rattle if it does it's normal. also run it on premium fuel.
 

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There shouldn't be a knock, even if the defective Motronic chip was replaced. that caused a hesitation around 3K rpm?

a common problem people have when first getting on an LT is that they are used to mcs with more low rpm torque when starting out in first. It takes practice to get the hang of releasing the clutch and applying the throttle without slipping the clutch--plus your can run the LT up to 5K before shifting gears, unlike my HD that I'd shift at 3K or less.

By now you have discovered that one must keep the front fork perfectly straight ahead at less than 5mph or she is going to go down.

here in arizona with summer temps over 100F I use our regular gas and have never had a knock.; engines that need high octain gas can knock on regular gas.

Untill someone with an exact answer comes along, I hope my post helps.

Best from t'son
Bob
 

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Hi all .Ive just bought a 99 K1200LT with 26,000 miles on the clock its in fantastic condition and im over the moon with it . I purchased her when my old Triumph Trophy let me down in Scotland on holiday when I was 400 mile from home and just decided on the spur of the moment to change it. I have to say its fantastic to ride and I haven't experienced comfort like it! The only little problem ive noticed is when I first pull away in first I get a harsh Knock Knock not every time and doesn't seem to do it after the very first take off . But leave it a while and pull away again it will do it once again ? Does anyone know how to cure it or know what it might be ?
many Thanks Edge
Your description of the 'event' almost describes the sound made by the ABS system doing its initial self-diagnostic check - usually within the first few meters of travel at the first start of each ride. The red blinking dash lights then go out, and you won't hear that sound again until you next start a new ride from 'ignition on'. It's a normal feature. :)
 

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You are on it Dick. Watch the ABS lites they will go out at the time of the "ABS self test autio output".

BobG
 

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Hi all .Ive just bought a 99 K1200LT with 26,000 miles on the clock its in fantastic condition and im over the moon with it . I purchased her when my old Triumph Trophy let me down in Scotland on holiday when I was 400 mile from home and just decided on the spur of the moment to change it. I have to say its fantastic to ride and I haven't experienced comfort like it! The only little problem ive noticed is when I first pull away in first I get a harsh Knock Knock not every time and doesn't seem to do it after the very first take off . But leave it a while and pull away again it will do it once again ? Does anyone know how to cure it or know what it might be ?
many Thanks Edge
Hi Neil,
I'm thinking you may be describing "K-bike" rattle, although the ABS self-check is another good possibility.
I'll dig through the archives here and see if I can find old posts on the subject of K-bike rattle. You can recreate the rattle by holding the bike at a stop with the front brake and at the same time slipping the clutch to slow the rpms. On some bikes, the rattle sounds really bad and makes you think something is really wrong with it.
In summary, K-bike rattle is a characteristic, "can-of-rocks" kind of sound emanating from the engine a low rpms.
It drove me nuts when my 2000 K1200LT was new. It has become much less noticeable over the years and I don't even notice it now at 94,000 miles.
Don't worry about this at all.
Congrats on your bike. I'd love to have a 99 with only 26,000 miles on it. I've had my 2000 since new, and wouldn't trade it for anything.

Addendum: okay, found one of my old posts on the subject: http://www.bmwlt.com/forums/showpost.php?p=313926&postcount=13
 

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My '00 makes the same sound you describe. To me, it sounds like a preignition rattle of some sort, but I'm using premium without ethanol so that shouldn't be an issue. My bike has about 38,000 on it (bought it 3 years ago with 18,000).

We did a 3,500 mi, 9 day trip this spring on it and it ran like a champ in weather conditions that varied from 36 degrees to 88 degrees and from 900' above sea level to over 12,000 in the Colorado Rockies.
 

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If it is like one-time "kling-klang" during the take-off followed by ABS-lights turning off (first time) then it is most likely ABS doing take-off-test. That test will be repeated with some cycle when stopping and taking off. If I remember right it is something like every 3rd or 5th stop + possibly some time in between.
 

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Also if you let the RPM drop below 900 as you are rolling out you will get a growl of the gears in the drive train in the engine. Here you can see two of the three gears that make the noise at low RPM light load. The crank gear and alternator/ starter drive gear are visible in the first photo while the output shaft gear (connects direct to the clutch) is visible in the second photo.
 

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Hi all .Ive just bought a 99 K1200LT with 26,000 miles on the clock its in fantastic condition and im over the moon with it . I purchased her when my old Triumph Trophy let me down in Scotland on holiday when I was 400 mile from home and just decided on the spur of the moment to change it. I have to say its fantastic to ride and I haven't experienced comfort like it! The only little problem ive noticed is when I first pull away in first I get a harsh Knock Knock not every time and doesn't seem to do it after the very first take off . But leave it a while and pull away again it will do it once again ? Does anyone know how to cure it or know what it might be ?
many Thanks Edge
Mine does that also. I can't say for certain it isn't the ABS self test as others have said, but I don't think so. Mine also does not do this every time, but seems to mostly do this the first start of the day. It feels almost as if a one way clutch is letting loose, but I don't think the LT has one. I both hear it and feel it and it happens as soon as the clutch begins to engage and before the bike is even moving, which is why I don't think it is the ABS self test. It feels like there is slack in the drive train being taken up as soon as the clutch starts to turn the input shaft.

I wondered what it was for a while, but after 7 years and 43,000 miles with no ill effects, I just accept it as yet another BMW quirk. :)
 

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One other possibility. The LT contains a drive-line shock absorber system. Depending on how hard you brake and wether you use engine braking, you can get a negative or positive pre-load on the system and it will "clunk" when braking or upon acceleration. Mine commonly clunks when I pull into my garage after stoping in the driveway and allowing the door to open. It is a separate, distinct noise from the self-test on the ABS which on my bike has a rather tinny noise to it. The drive-line clunk is a good solid clunk and is nothing to worry about.
 

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My 99 LT began this at about 28K miles. On mild to moderate acceleration it sounds like banging on a coffee can with a ball-peen hammer! It's more pronounced as the engine warms and occasionally doesn't do it all from a cold start. It's minimal or nonexistent under hard acceleration but very pronounced under 4000RPM. At first I thought the engine was missing but after a hundred-plus hours of tear down and component by component diagnostics I've concluded it's a combination of pinging and backlash in starter and alternator gears. I've now encounter similar vintage LTs with higher mileage that have never done it and others that are worse than mine. It's still annoying has hell but it hasn't changed or affected reliability as far as I can tell for last 20K miles. If I dial up like a racer and keep the "RemPems" above 4000 my noise goes away. This makes for jumpy urban riding but relieves my guilt for flogging it like I stole it.
 

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One other possibility. The LT contains a drive-line shock absorber system. Depending on how hard you brake and wether you use engine braking, you can get a negative or positive pre-load on the system and it will "clunk" when braking or upon acceleration. Mine commonly clunks when I pull into my garage after stoping in the driveway and allowing the door to open. It is a separate, distinct noise from the self-test on the ABS which on my bike has a rather tinny noise to it. The drive-line clunk is a good solid clunk and is nothing to worry about.
Do you mean something other than the rubber damper in the drive shaft? My noise is a distinct mechanical metal-to-metal sounding noise.
 

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Mine sounds like a cement mixer when starting out at low rpms in first.--can't hear it in any other gear, too much other noise.


bob
 

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Do you mean something other than the rubber damper in the drive shaft? My noise is a distinct mechanical metal-to-metal sounding noise.
Yes there is a rubber damper in the output shaft. I know of one where the rubber was GONE. Not sure how that happened. Here are some shots of it. The crankshaft drives the gear and the clutch housing is tied to the shaft.
 

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Do you mean something other than the rubber damper in the drive shaft? My noise is a distinct mechanical metal-to-metal sounding noise.
Yes. There is a seperate damper which I think is in the transmission. It has (I think) a cup with hard rubber internal veins coupled with a disk that has similar veins. They fit together. This makes for a damped driveline lash. Mine makes a pretty loud metallic single clunk when it does it's thing which is whenever I stop in the drive, open the garage door, and ride in with the driveline warmed up. When I apply the brakes (rear I presume) it sounds like someone hits the transmission or the under side of the bike with a big rubber mallet.

Found it. In the engine on the output shaft. Numbers 3 and 10 on the microfiche.
 

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Yes there is a rubber damper in the output shaft. I know of one where the rubber was GONE. Not sure how that happened. Here are some shots of it. The crankshaft drives the gear and the clutch housing is tied to the shaft.
Interesting. It is hard to imagine this making the sound I hear occasionally, but the again I can't imagine what else it would be. However, as long as it keeps on making the sound ... I won't complain! :)
 

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Yes. There is a seperate damper which I think is in the transmission.
There is a bit of a damper on the input shaft on the transmission. Items 1 and 2 give a little on rotation input and compress a substantial spring inside of 4.
 

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Try posh petrol but it could be s clutch rattle or front fork rattle as you pull away... 25000 miles and how old ? its a bike and the design is .... older just ride it an enjoy the nice bits ... pull the bits off this winter and make it better ... :)
 

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Mine makes the bag if rocks sound. Every now and again I get concerned, then I remind myself that it's the bag of rocks sound, and just keep riding....
 
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