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Vibrations

4K views 14 replies 7 participants last post by  Lui Boy 
#1 ·
So I kinda hate winter, cuz after that many months of not riding you kinda forget what the bike does and doesn't do. What sounds are normal, what vibrations are normal.

Right now I'm dealing with a weird vibration. It seems like for one the whole bike is vibrating more at highway speeds then it did before, and its like a... higher pitched vibration. If that makes any sense to anyone else. And weirdly enough I notice it more on the right highway footpeg.
Now of course I did a few things this winter/spring. New Metz tires, greased the spline, RR. Today I just drilled the baffles, but I noticed this before that, so they are innocent.
First thing I did trying to track it down was tighten all the bolts on my highway bar, and highway pegs. Checked the torque on the front wheel. Today I changed the oil, but I haven't gotten it up to speed yet to see if it may have smoothed out the engine or anything on that end.
I hate unknown issues.
HELP
 
#2 ·
New/different tires can make a bike feel completely different, but are you a 100% sure that the vibration was not there before and you just kinda noticed it now?
Tires balanced the same?

I would check the motor mounts , but unless the vibration seems exsessive, not sure I would be to worried about it.

The hardest part here of course is trying to describe what it feels like. Much like odd noises, one really needs to experiance them first hand to get a clear picture of what you are talking about.

The bike is a V-twin , that does "vibrate" and more so at certain speeds and less at others. If the mirrors seem clear and there is no loud sound accompaning the vibration...and the handling seems fine, you likely have nothing to worry over.

Men have gone mad trying to pin down the causes of odd sounds and vibrations on their bikes.
Try riding more and see if you just forget about it after a while.


KM
 
#3 ·
No I am not 100% sure. Like I said winter screws you up. You forget all the little things, and then when you go off and make a bunch of changes at once, it makes it hard to say what has done what.
Yeah the tires have been balanced, not sure what you mean by 'balanced the same' though. Maybe I need to spend the loot and get some 'Ride-on'.
Mirrors seem clear.
How would I go about checking motor mounts?
The handling is better then ever, thanks to the Metz. Maybe they just need to get broke in more. Who knows, maybe my 'princess and the pea' ass is feeling the little rubber feathers on the new tires...???
And believe my I understand about going mad trying to find noises. If I can at least know its okay, then I'll be okay. Or at least have a plausible explination then I can forget about it.
Now I guess I just have another excuse to get some progressives.
And dude I am always trying to ride more.
 
#5 ·
I had the same vibration on mine and could feel in the right peg. I syncronized the carbs. and it took care of the problem. The rear cylinder was pulling harder and causing the vibration. Some people will tell you the CV "constant velocity" carbs do not need to be syncronized, this is not true. If the butterfly linkage is not synced and one opens before the other that cylinder will make more power and cause the engine to vibrate.
 
#6 · (Edited)
Lance's idea of checking the carb synch is a good one. I did not think of it as I was going on the "not a pre-exsisting condition" issue.

But cold storage over the winter could have "shrunk" the rubber in the motor mounts. If you just loosen one at a time and retorque it that is all you really can do.

And ALL bikes vibrate...Niteriders bike may not do so excessively, but all do and V twins have their own "frequency" ...it is really a matter of the intensity of the vibration that matters. The Vulcan is rubber mounted and the engine has a "balancer" that tames the vibes pretty well. But the thing does shake, it is just less noticable than say a older model sportster.

Are you wearing the same boots? Oldly this can make felt vibrations in the pegs seem different too.(Why don't you have floorboards by now?)

I would hazard a guess that there is nothing "wrong" and you might be able to smooth out the vibes with the above suggestions......or maybe not.

KM
 
#7 ·
He could just take my single cylinder, push rod havin, old school even though it's a 2006, RE out for a spin. One look in the mirrors...worrying about his
Vulcan's vib will disappear ...me thinks.
 
#9 ·
The carb sync makes sense. I did that last year. but haven't done it again. this bike is so easy to do it on too. My ninja you had to remove the gas tank and set up a funnel to feed it fuel so you could keep it running long enough to do it right.

I havent done the ol screw adjustment on the carbs either. I've read some of the threads on it, but still not understanding it 100% yet.

Are the motor mounts bushes easy to replace if I wanted too? are they something you can do one at a time?

same boots. I did have a foot transplant though maybe thats it...
 
#10 ·
KM I havent got floorboards yet, cuz I haven't found any I like, no offense to yours. I kinda wanted to modify the Kuri ones, so i could match my grips, and highway pegs. and the other Kuri stuff I want to get. I know slave to fashion.

At least I don't have to have every article of my clothing have Kawi logos on them, like some other biker brands loyalists do...
 
#11 ·
Well I balanced the carbs, and adjusted the mix screws. Hopefully that'll take care of my Mystery Vibration. I took it out but its to cold, when it cold out and I ride, my right knee (the side the alleged vibration is on) starts to bounce. So when ever the hell this crappy state warms up I'll find out.
 
#12 ·
Still some vib. But now with the exhaust drilled out to 8, there is more vibration, period now. I really wasn't going for that, shoulda stopped at 6. Unless cuz I didn't do the sync with engine at 4k. I only did it at idle. Maybe that'll straiten her out.
 
#13 ·
I also got the vibration that is really noticeable at the right peg where my right foot moves to the right due to vibration. I couldn't see anything aswell on my side mirrors.
I have check all engine rubber mount support. They are still in one piece condition, however, they are all hard already nearly having a plastic condition. Vibration starts at 30kph.
 
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