Still getting vibration on TS1 225

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celt
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Sun Jul 26, 2009 11:40 pm

On the old site I mentioned I was getting bad vibration

After twisting camlam crank awhile back, I replaced crank with MB Alpha crank and lightened flywheel (2kg).

Whilst taking it easy to bed the crank, vibration was a big problem. I had made sure that engine mounts were not over tightened, swapped sundance grips, etc. I had also replaced engine mount cones to eccentric as manifold just touched the frame unseated, just to make sure.

Problem still present

The problem was not present before twisting camlam crank, so process of elimination.

Changed flywheel to heavier flywheel (short fin), vibration was reduced but not rectified. Fearing that this second crank maybe out of alignment, stripped scoot.

Crank was checked by an engineer who builds 2-stroke cranks who said the webs are out by 2 thou of an inch, but he said that is within tolerance and the conrod is running true.

So I am frustrated in knowing what this vibration could be. With the lightened flywheel fitted rode 40 miles and found that 2 wires had vibrated loose from rectifier. Even with heavy flywheel getting pins and needles in hands after 10 miles

Any ideas will be greatly appreciated

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tony
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Mon Jul 27, 2009 12:37 am

Main bearings are ok?
Sponsors: Performance Tuning. Ve Uk. Scooter Center Koln. LTH . DRT

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soulsurfer
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Mon Jul 27, 2009 8:05 am

What rear suspension do you have?
Turn On, Tune In, Cop out!

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celt
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Mon Jul 27, 2009 11:18 am

tony wrote:Main bearings are ok?

New SKF and FAG bearings fitted with with new crank, just under 500 miles run with new crank

soulsurfer wrote:What rear suspension do you have?
A standard Escort rear shock

eibargum
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Mon Jul 27, 2009 12:55 pm

I take it you pulled the crank in gently :?: , only asking because you would still think its the crank. I,ve only twisted 1 before and you could see a eccentric movment on the flywheel when you pressed down on the kickstart,the web,s had also moved off the pin, is there a gap between the webs and the casing, might be worth taking the flywheel cowl off to check for the eccentric movment first, good luck with it and let us know when you sort it.

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TheSeeker
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Mon Jul 27, 2009 5:23 pm

Loose headset?

Ben

eibargum
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Mon Jul 27, 2009 5:28 pm

you may be onto somthing there Seeker, when the front forks are loose the whole bike shake,s, even on the stand.

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ABC
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Mon Jul 27, 2009 5:32 pm

play in fork bearings? as you say your hands go numb

eibargum
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Mon Jul 27, 2009 5:44 pm

Easy to check for, put the bike on the stand with the front wheel off the floor, grab the wheel and see if you can rock the forks back and forth, simples.

J1MS
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Mon Jul 27, 2009 6:18 pm

The main faults are usually somthing loose rattling, Headset, Metal butty box, center stand, or a panel vibrating....

None of the above and you are sure you havnt got a new twisted crank or damaged main bearings...

Then my main suspects would be the choice of engine mounts (Solid type) or the way they have been put in (Std type) anti vibration holes in the wrong place...
The only other problem thats caused Vibes on one of mine was a Full Circle Crank... Vibration below 4,500rpm caused white finger above this it smoothed out but slow riding caused the stand, butty box ,cowling bolts and one foot board to vibrate loose... I changed the crank back to an SIL with a Yam rod and the Vibes went....

Hope theres some info here that helps... cant think of anything else...

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