Horrible high rpm vibration

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MillaMeter
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Horrible high rpm vibration

Post by MillaMeter »

Hi,

Basically, anything above 5000rpm the bars just vibrate and it really really hurts my hands. I went to book my Dyno run again today so going down the A41 hurt like hell! The vibration isn't big like harley or anything, it's just a really fine 1 that makes your hands tingle when you get off the bike.

1 thing I do know though, is that I had this vibration before my lil spill 2 weeks ago and after riding the bike home, the vibration went. Bike is now back on the road and vibrating again :(

Any ideas?

Regards

Rich
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RedexRobB
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Re: Horrible high rpm vibration

Post by RedexRobB »

Wheel balanced?
MillaMeter
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Re: Horrible high rpm vibration

Post by MillaMeter »

Nah it wouldn't the wheels, I can feel the vibration stationary. Rev the bike on a spot and it does it.

Regards

Rich
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RedexRobB
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Re: Horrible high rpm vibration

Post by RedexRobB »

In that case it might be the motor, check all the engine mounts are done up tight. I think NorthernAndy had the same problem a while back, not sure if he got it sorted or not but might be worth gettin in touch with him see if he sorted it.
MillaMeter
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Re: Horrible high rpm vibration

Post by MillaMeter »

Cheers Rob,

I've checked all engine mounts and they all seem to be fine except the 1 on the right hand side of the frame, 2 of the bolts that hold this little bracket to the frame were missing :shock:

Instantly put 2 new bolts in there with crinkle washers to stop them working their way lose again. Took the bike out for a spin at it's still vibrating :(

The bike starts vibrating above the 5000rpm mark right the way to redline.
The vibration isn't chunky and blocky, but like a really fine vibration that makes your hands feel like a 1000 nettles have stung ya.

Now I was told the cams and valve clearences chould do with a check and may be the cause of the problem.

Any other ideas?

Regards

Rich
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zimm
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Re: Horrible high rpm vibration

Post by zimm »

carb balance ?

rotted baffle in stock exhaust ?

camchain on its way out ? (means the camchain tensioner is nearly fully extended .. this can sometimes pickup vibration)

worn camchain guide ?

loose sparkplug ?

loose airbox ?
MillaMeter
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Re: Horrible high rpm vibration

Post by MillaMeter »

zimm wrote:carb balance ?

rotted baffle in stock exhaust ?

camchain on its way out ? (means the camchain tensioner is nearly fully extended .. this can sometimes pickup vibration)

worn camchain guide ?

loose sparkplug ?

loose airbox ?
Done carb balance the other day, it seemed to mask it a lil bit.

No idea on the cam chain and tensioner or the guide.

checked spark plugs, all seem to be good.

airbox is fine too, had a look today.

The bike has done 40800km and i'm not sure if it's been changed already. (doubt it) I'm trying to find a decent grease monkey to fit the cam chain and tensioner for me as I really dont have the time. Any decent garages in Hertfordshire?

Regards

Rich
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diesel
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Re: Horrible high rpm vibration

Post by diesel »

i have the same prob. my hands hurt like hell after i been on it. someone suggested bar ends but i have solid clip ons lol. sounds weird but maybe thicker or better gloves?
Quicker Than Yngwie

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MillaMeter
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Re: Horrible high rpm vibration

Post by MillaMeter »

Hi,

I think I've found the main cause of the problem.

Take the tank off and airbox and hook up some carb syncs. Adjust your idle screw so that the bike is ticking over at 3000rpm but make sure the engine is warm before proceeding to balancing. I noticed with my bike that when I balanced the carbs on idle (1250rpm) it ran great, soon as I took the bike up to 5000 it vibrated my hands to hell! So balancing the carbs whist the engine was sitting there at 3000rpm made my vibration dissapear! Result! :smt003

Give that ago maybe?

Regards

Rich
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gt185
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Re: Horrible high rpm vibration

Post by gt185 »

I've been experiencing the same problem, so I've been following this thread.
I swapped the carbs on my H2, for ones off a later L model, so I could run
the cooling system through them to prevent carb icing.
Rushed the re-assembly, and never got round to balancing the new set-up,
so the vibes may be the root of the problem.

Read somewhere to set the idle higher than normal, to keep the bike
running during balancing. Personally I couldn't get the bike to stay running
on idle with the air-box etc removed. Tick over had to be higher just to
keep it going.
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Re: Horrible high rpm vibration

Post by gt185 »

Been trying to balance my carbs, to see if I could rid myself of the vibes which are
the same as described in this thread. All of the vibrations actually come from the
carbs, and none at all from the engine itself.
Not sure I'm having much success with the balancing, and it all seems to keep changing.
My mates vacuum gauges are the type with the metal rods that slide up and down in
the glass tubes.
Any ideas why the carbs would be vibrating, and how to fix (or balance better)?
Not knowing enough about carbs, I don't understand where the vibrations ar coming
from. There are no moving parts as such, are there?

Cheers
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