Vertical Play In Swing Arm Linkages
 

Hi, I've just bought a beautiful ST4 which has been lovingly maintained with lots of dealer history. One thing worries me though, if I lift the rear wheel while the bike is on it's centrestand there is a couple of mil of play vertically somewhere in the swingarm or suspension linkages.
I've heard that early ST's suffered from issues with the swingarm pivot which wore unevenly and is not a simple fix, but i'm hoping it's not that since there is no sideways play.
Any ideas?

When I build bikes the rear suspension is normally like that until I tighen all the bolts up

So I suggest checking all bolts are tight, as they may have been removed to copper-slip them
Other thing to look at is the Rod end bearings in each end of the ride height adjusting bar, they could be worn and have excessive play

A new shock cured the same problem on my ST4, the bushes wear and they are not replaceable.

Check the pivot bolt behind the frame bungs, mine has loosened several times, and that's the first sign it's slack

Another favourite is the rear engine mount loosens up. The play comes fromt the engine rocking in the frame........

Had the same problem. There are two small bushes in the top of the link shaped like top hats, on mine these were worn. Two new bushes and all sorted.