Slight 'clunk' when accelerating

[AussiXS11G]

sounds like this thread to me.....

http://xs1100.com.au/forum/index.php?topic=1990.msg12973#msg12973

[petejw1966]

also check ur uni joint for any free play,
u should have none.

[steptoe]

in a certain gear, 1st or 2nd or thru gears,? giving it a fistfull or normal revs?
check the middle drive for oil level,, or put the bike on the centre stand and see what you can hear or feel rolling the rear wheel back and forth
 or it has come before, an easy look might be the drive shaft into the diff spline being super dry and worn,, other than that it,s probably internal

[alice]

Seems as though on the odd occaision, when I first take the bike up to 80-90kph the XS11 has sort of a sight 'clunk' in the drive train. Any suggestions on what i should check??