I have a hybrid 523/568 that I put together for my '90 Shadow last year. From the beginning, this transmission has had a neutral rattle that has bothered me. If the clutch is out in neutral, it literally sounds as if the gearset is rattling just a bit. It only happens when the trans internals are moving, meaning if I put a bit of pressure on the clutch pedal (to put pressure on the TO bearing), nothing changes. The rattle does not go away until the clutch is fully depressed. I've also noticed that it happens when there is no accel/decel load on the trans in gear. For example, in traffic, if I'm in 1st gear, rolling, clutch out, if I'm accelerating there's no rattle. If I'm decelerating, no rattle. If I'm coasting with zero load on the trans, I ca hear it if I'm next to another car. To me, it seems like there something is a bit too loose, but I don't know what. When I put the trans together, I shimmed everything up as I always do. I ran the car through drag week last year with it like this and the noise hasn't gotten any worse, but it annoys me.

I haven't torn it apart to look at it, but I'm looking for input. Anyone deal with this before and figure out what is wrong?

Thanks,
Pat