by nickwill » Mon May 04, 2015 12:55 pm
Danny,
Chris Powell did some for me a couple of years ago. I put the new mounts in the freezer overnight but didn't have any means of heating the casing, and there were no problems removing the old mounts or putting in the new ones, though the old ones were probably only 3 years old so hadn't had long to get corroded. It might be more difficult to remove 20-year old ones if that's what you've got.
To get at the mounts you need to remove the engine bar and drop the engine unit - with it still attached at the rear shock it should just pivot down. I can't remember what bits we removed to make access easier. I think the carb had to come off - there are probably details on the Net somewhere. The main thing to be wary of is don't use too much brute force if the mounts are stuck, the lugs on the engine case can crack if you start smacking them with a hammer. Be careful refitting the engine bar - it sits in steel cones and needs to be carefully lined-up with the holes in the cones and mounts before tapping into place with a soft hammer or wooden block or you can damage the threads on the bar.
Nick