older XT600 excessive vibes vibrations
 

Hi All,

can anyone give some pointers as to what things to check or adjust to decrease the level of vibrations on an old XT.

I know its a single but this one vibrates terrible compared to a previous one, anything over 50mph numbs feet within a couple of miles.

many thanks

here she is, awaiting your help
http://lh6.ggpht.com/_aJzSBN66Sc0/Sg...0/DSC04191.JPG

Engine mounting bolts correctly torqued?
 

Hi Lamin,

I have been thinking along similar lines though by bike does not vibrate as bad as yours from your description.

The first thing to check is that all the engine mounting bolts are tightened to the correct torque, including the head steady ones.

The most obvious reason would be worn engine components, especially crank bearings, or a previous owner having removed or mis-timed the balance shaft (some people believe that removing it increases power or throttle responce).

If you remove the lft hand side circular plastic inspection cap at the end of the crank shaft you can gentallt lever the end of the shaft to look for free play in the left hand main bearing. I have a little free play here but don't know how much is normal for a ball or roller bearing.

Good look, I will be watching i the hope that you may throw up the answer to my problem too.

Mark

Hi Mark,

thanks, yes, I've been all round the engine mounting bolts.

also the swingarm pivot bolt , when I torqued up the pivot bolt after having the swingarm out I seem to have a bit of 'sticktion' in the movement

I did find this from mr lambeth in the archives:-

"Severe vibration from xt6s is often caused by a loose swing arm spindle nut and lower engine mount (allows engine to rattle against frame)
I have seen this problem on many high mileage bikes - if the problem is left too long the swing arm bearings will need re shimming to avoid the arm going tight on re-tightening."

I wonder how do you check if the swing arm bearings will need re shimming?

thanks
andy

quote "when I torqued up the pivot bolt after having the swingarm out I seem to have a bit of 'sticktion' in the movement"

thats when you need to shim the bearings. :thumbdown:
the swingarm pivot runs through the rear engine mount and there are a couple of steel inserts in the crankcases which wear away through the vibes, this allows when the swingarm pivot bolt is tightened to compress the frame slightly and can bind on the swingarm pivot :(
you can replace the inserts or re-shim the swingarm bearings to give the right freeplay

thanks, I've ordered the inserts/collars as they are only a couple of quid, do you know what sort of fit they are in the crankcases, presume they aren't to difficult to push out & install....

they can be a bit of a pig to get out as you dont have a lot of room to work :thumbdown:

hi there my 85 43f got quiet viby a while ago ,the front foot peg mounting bolts were a little loose ,also the rear lower engine mounting bolt was too . after these were tightened up it was back to normal ,i will now keep a check on these regually , zigzag

shim washers
 

anyone know where I can get some shim washers, I've drawn a blank locally

thanks

shim washers spacers swingarm pivot
 

just for future reference and searches, if anyones stuck you can get shim washers here

Washers

cheers