Vibration on acceleration
 

Hi Guys

I have a very early model 34L (engine# 0000552), and i am experiencing some strange vibration on acceleration! It is only on acceleration and there is no vibration when in gear with the clutch depressed or on neutral. The wheel bearing is also fine.

I have searched the site and have not found much on locating the source of vibration. Could this be due improper chain tension? My seems slightly slack.
How do i go about finding the problem as i dont want do any thing that cold result in damage to my baby.

Im sure some of you guys can help me! I look forward to a response!:taz:

Hi, welcome to HU, do you have any more information about the nature of the vibes?do you have an idea where the vibration is coming from is it chassis or engine related, I have had a similar problem recently on my road bike and it was traced back to head bearings, things I looked at were as follows

Correct rear wheel alignment
Correct drive chain adjustment and general condition of chain and sprockets
Wheel bearings
Possible warped braking discs
Correct brake pad fitment no uneven wear characteristics
Correct tightness of engine mounting bolts
Swinging arm, check for play in the movement


All the above was OK, head bearings have a dramatic effect on handling characteristics and can cause judder and vibes but there are many other potential causes,

Do you experience any other sensations especially with your hands off the bars, any effects under braking? How long you had the bike, do you know its history, has it been dropped or repaired (possible bent frame, forks or yokes)

Don’t know much about XT engine issues maybe a simple problem in that department however it would not hurt to check the above anyway. Cheers - Greg

Warped clutch plates can be added to the above mix.

How about other components of the drive train? Like the gearbox? Any worn/broken gearwheels could cause vibs under load...

Do you experience the vibes during crusing as much as under acceleration?

Jens

GOOD Vibrations!!
 

Hi there guys!!

I met up with Wingnut, in the Fair Cape and had a ride on the problem bike..... The vibrations are really bad on accelaration, but unlike my mate I feal they are coming through the steering Head assembly??? Any Ideas.....

THE rear sprocket is worn and the chain looks stretched.....as the rear wheel is so far Back on the swingarm that the snail cams dont even touch the adjuster lugs!!!!! This could cause the problem, although worn gear box gears do seem like a possible cause as well?

How would you check that!!!Without dissesembly,PLEASE!:eek3:

Wingnut could you give us an update. Happy fixing
Cheers Bryan

Errrr yes.. Very much so !! The cams arnt even in contact so you dont even know if the wheel is alighned.. Knackered sprokets and chain are making things worse for sure.. First off he had to get these replaced as a priority and get a new chain of the correct length, making sure the chain has enough links in to get the rear wheel off, but enough to take up the slack when it wears.

If your thinking its coming through the front end then i think you should check the headstock bearings as a priority.. You need to check for freeplay and ease of movement. With the front suspended off the floor there should be no movement in the bearings and they should only be loose enough to let the bars move side to side under their own weight... Idealy you should take the bearings out and check for pitting but try nipping up the ring nut at the top and see if it sorts it.. pack some grease in there too.

If you can safely rule out the headstock bearings, check for play in the wheel bearings.. If they are fine then check the wheel is true and the forks arnt bent etc.