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Discussion Starter #1
Got a problem on my '99LT that's got me a little stumped. Maybe some of you can help me diagnose the problem. Late last season I noticed a buzzing sensation coming from the engine that has become more pronounced this season. This is a vibration. The engine runs smooth and has no issues (no hesitation, stalling, etc.), except for this feeling which is most noticeable at idle (neutral) and low rpms only. It smooths out at higher rpms. The tupperware on the left side vibrates and rattles although everything is in tact and tight. The right hand grip also vibrates. It runs smoothly and is still getting 50-54 mpg. The bike has 68k miles. Meticulously serviced, mostly by myself, except for valve clearance adjustments (last checked at 60k by dealer-no adjustments required) and the cam chain tensioner (replaced by dealer at 60k). Last major service was performed by dealer at 60K. Last tune-up service (plugs, all fluids, filters) performed at 66k by myself. Idle is at 1,000 rpm +/- 50. I would appreaciate any input before taking it to the dealer. Possible idle speed adjustment? Synchronization problem? Past due for a valve clearance adjustment? There is a slight valve clatter, but no more than has been normal for the bike for several years. Bike has full power, no smoke, plugs were burning clean and even when replaced. Other ideas? Thanks.
 

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does it have a sound other than a buzz? Plastic makes all kinds of noises that I know you are aware of. question that i have is can you tell if it is a metallic noise or is it plastic?
 

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Wrencher Extraordinaire
2005 K1200LT
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Almost every "Buzzing" thread I have seen ties back to the exhaust system. Either a broken flange /stud or a bolt touching the exhaust some where picking up the buzz. I would look there first.
 

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Discussion Starter #4
By buzzing I mean a vibration that actually shakes the hand grips. The only sound is that of the plastic vibrating. So there is some sort of vibration emitting from the engine at idle that is vibrating the entire bike. It runs smooth, but not as smooth as it should in my experience. It's similar to what a 4 cyl/4 carb bike would run like if the carbs were out of synch.
 

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Discussion Starter #5
Or maybe the idle speed is low. It's at 1000 rpm +/- 50. Does the fuel injection require any service?
 

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I have noticed since your original post that my bike idles at the lower spectrum 1000 +/- 50 well mine is the -50. I have synced the throttle bodies last fall, which smoothed out a lot of rattles. However my mirrors are like baby rattles. I will agree to check out your exhaust but just start feeling the bike all over while it is running to get an idea of where it might be coming from.
 

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Discussion Starter #7
The vibration stems from the engine. It is more pronounced now than in the past. Throttle bodies have not been synched. I've synched many carb set ups through the years using vacuum guages, but never throttle bodies. Can you tell me about the job?
 

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Discussion Starter #8
I've checked out the exhaust and it's all good. Suspect throttle bodies may be out of synch.
 

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This subject came up a few years ago on the old board, LT's with STOCK EXHAUSTS just have this Funky 3800/4200 rpm vibration, It comes from the occilations of exhaust pulses within the pipe and most have found NO cure for it but one :) .... a Remus exhaust system, yep installed mine and this funky vibration was history, go figure :dance:
 

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Could it be the tires or the fork? Like a wobbling thning which will make a resonance thrue the whole bike? Does it come at certain speeds ?

With my old Suzuki 1100 It wobbled between 60 and 90 miles and the whole bike was shaking like it had been in a freezing blizzard, but before and after it was a smooth ride. The problem there was the shocks and the fork!
 
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