Would anyone know how to replace the damping rod bushings on older kyb usd forks (1990 KX250). They are under the cartridge cylinder cap (where the cartridge holder tangs are). I have the race-tech replacements.
The cylinder cap looks like it may be threaded, but there is no peening like on later model kyb forks. I've tried heating the cylinder tube at the cap junction with a propane torch to no avail.
Is there a trick to getting the cylinder cap off so the damping rod bushing can be replaced?
It's really not a drama when you have the right equipment. A cartridge clamp and a cartridge holding tool make the job easy. For someone at home I would recommend that your put the blow torch back in the cupboard and do the following. Firstly the cartridge is threaded at the top and is held in place by copious amounts of loctite. In order to undo the top you should first break the loctite. Lay the cartridge down so it is supported at the threaded area. The back of a vise works well. Now tap around the threaded area with a hammer. Obviously we are not talking wild blows here. But the blows should be sufficient to do the job. Notch a piece of electrical conduit to fit into the notches at the top of the cartridge. The conduit should be long enough to extend beyond the top of the damper rod. You should have a hole drilled through the conduit large enough to accept a number 2 phillips driver (above the rod). Place a No. 1 phillips through the holes at the bottom of the cartridge. You should now be able to undo the cartridge with the assistance of another.
Terry Hay
Terry....you're up too early and thanks for the quick reply. I had tried all of the above without the hammer tapping, hence the heat application. On taking your advice, and tapping around the end where the cap threads into, it came right off, right hand threads.
I was thinking for awhile the cap was pressed in there or a liberal application of red loctite had been applied.