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Discussion Starter · #1 · (Edited)
Alright so I just purchase a new 675 and only have 500 mile on it. At 300 mile I made a slight chain adjustment, and started to notice a slight vibration and fairly noticeable (wife noticed it while on the back) noise coming from the rear end. The noise and vibration sound/feel very similar to new brakes before they are broken in. First thought was to tight/out of alignment chain. Doubled check everything and everything was spot on. Next I loosened the chain to max spec, and the noise/vibration is less but still there. Next pulled off the caliper and went for a ride, and to my disappointment the noise didn't change at all. Just now I pulled the rear tire to check the bearings and everything appears to be in good order. After putting it back together the problem is still there. My last guess is the counter shaft (which I am preying that it isn't :(). It only does it between 18-21 MPH, and completely disappears at all other speeds. Has anyone else had this problem, or what could be the possible causes? I have been riding/working on bikes for many years and never ran across anything quite like this.:mad:
 

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Check the alignment of your rear wheel. If it's out of alignment, something might be rubbing. Another thing to look for is debris of some kind stuck in either the countershaft sprocket cover or chain guard. The last thing to look for is some kind of tight spot in the chain. The chain shouldn't be screwed up so fast, but maybe you have a faulty chain. I doubt it's anything serious.
 

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Discussion Starter · #3 ·
Thanks for the reply Will, however I have checked the alignment so many times now, it is not even funny. I think it comes down to that the Daytona doesn't like to have the chain on the tight side, because today I took my friends street triple for a ride (which his chain is tighter than mine), and it has the same vibration/sound (although you wouldn't notice it if you were not looking for it) at the same exact speeds. Bottom-line is I believe I just have to run the chain a little loose and stop being so anal about my maintenance.
 

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You may want to perform a very detailed inspection of your chain. Pay particular attention to the master link. If it was riveted together with a little too much force, that link will have a tendency to bind just a bit as it passes around the counter shaft sprocket.

The chain will stay a bit bent as it unwraps from that sprocket and then it creates a slight pulsing vibration as it straightens back out.

You might have to take off the front cover to be able to get a good view of this. As the chain wears it will improve as that link loosens up a bit.

Jeff
 

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That is very interesting. I have been fussing with a strange vibration for 4000 miles now, but mine is between 50-55mph prominently. If paying attention on smooth roads it can be noticed at other speeds. I've always thought it was the chain just having been stretched funny Now if ran on the tighter side of spec the vibration is terrible, so I try to keep it sloppy, but it nevers goes away. I feel it as a pulse-like feeling, that I would imagine is once per chain revolution. There is a clear tight and loose spot under inspection, but I wouldn't say it is much more than average.

I want a new chain regardless, but I'll have a look at the master link, and I've already taken off the front cover so I'll have look and see how things are going.
You may want to perform a very detailed inspection of your chain. Pay particular attention to the master link. If it was riveted together with a little too much force, that link will have a tendency to bind just a bit as it passes around the counter shaft sprocket.

The chain will stay a bit bent as it unwraps from that sprocket and then it creates a slight pulsing vibration as it straightens back out.

You might have to take off the front cover to be able to get a good view of this. As the chain wears it will improve as that link loosens up a bit.

Jeff
 

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Vibration from rear end at 18-22 mph

I have a new Speedmaster. It had 147 miles on it when it came home from the dealer. It drove as smooth as silk. A week or so later, at about 350 miles, my accessories arrived at the shop, so I had them installed (windshield, bags, touring seat). When I drove away, I noticed a distinct "vibration" at or about 20mph coming from the rear and also noticeable in the footpegs. I called the shop when I got home to discuss the symptom. They assured me everything would be fine. At the 500 mile first check-up they added air to the rear tire. Now the vibration was more noticeable. I called them again. They had me bring the bike in for another evaluation. The salesman and mechanic both confirmed the symptom.

Basically, the vibration is present with or without the motor running. It's only present when very little to no load is on the motor, i.e. with the clutch pulled in, the motor off and coasting, or with very gradual throttle.

Despite the definition & explanation, the mechanic reduce the idle speed. I really don't understand why, but that's what he did.

And, no, there is no appreciable difference in the vibration. Pretty much they can't identify the source, so they're trying anything.

I not satisfied and I plan to bring the bike back to them for another look.

If and when they correct the annoying symptom, I'll post the solution.

Personally, I think they should be looking at the tire for cupping, the wheel balance, alignment or some other mechanical assembly common to the wheel, ie the rear brake.
 

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I noticed the same vibration on my new SE and from what I can recall, I think I noticed it in the first few miles and attributed it to a new chain. for the most part I only hear it when coasting with the clutch in or in neutral. It sounds/feels like a humming/rubbing/thump. I now have 650 miles and still notice it so I will have the dealer look into that along with the coolant leak I found late last week, The annoying ticking im hearing from the engine at steady rpm's, and the missing mirror nut from assembly.....Wouldnt trade it for the world though!
 
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