How to extract a GT550’s rear shocks

Q. I’ve bought myself a project bike – a 1988 Kawasaki GT550. It was completely dead but everyone’s help on the MCN forums has got it through the MoT, so firstly thanks to all.

I now have a bit of a problem with the rear shocks. The air suspension units were shot so I’ve bought some standard ones and am trying to put them on.

The problem is that the bolt which threads through the top of the shock and then through to the frame is just spinning in its hole. It didn’t take much to turn it in the first place. Odd I thought.

Then I moved onto the bolt the other side and it’s exactly the same. They just spin and spin with no sign of the bolt actually coming out. There is no nut the other side – just a round housing.

I’m guessing it’s rusted in there somehow, but any suggestions would be very much appreciated.

I’m praying I don’t have to drill the thing out.
Bannerman, MCN forums
 
A. If it’s all original you should be looking at domed nuts over pins that are welded into the frame.

A lot of neglected GT550 frames rust and fail the MoT due to shock mounts, so there are a variety of non-standard welded up solutions, like a couple of spot welds to the back of the shock mounting pin to hold it solid while undoing the domed nut on the outside.

If the rear of the stub is enclosed there’s very little option but to use a nut splitter on the domed nut to remove it, then once the shock is removed either weld or braze the stub solidly into position from the outside before fitting new domed nuts.

Or it could be that the treads have failed on the pin or in the nut.

Some GTs had a rack located on the upper shock mount, these were mostly just pinched by the nut so it’s possible this rack can touch and damage the mounting pins threads.

I think the nut may have to be carefully ground off.