As said before.
On '98 you have the M97 gearbox, which has a lot less problems than the M94 gearboxes (1994-1996 models).
Mine is '98 1100 also and I get normal amount of metal-grain collected on the magnet at every service when I inspect it.
I change gearbox and finaldrive oil at every 10Kkm, the same time as engine oil, so it's all the oils every service for me. Since it's so easy yet cheap to change the transmission oils. If you ride your bike on very bad roads think how much work they have to do.
If the metal particles aren't more than few millimeters long "slices" and no more than one millimeters thick sticking out of magnet then it's a normal wear for gearbox and nothing to worry about. And very fine metallic dust mixed with oil, "gray paste" as you call it, is absolutely nothing to worry about. Typical bigger metal particles on my gearbox magnet can be relatively long (few millimetres) but very thin. My bike is now over 80,000km, and it's been the same from the beginning.
On final drive magnet I mostly get only metallic dust - very fine particles "gausially" collected around the magnet. Reading at UKGSer or ADVrider - if big noticable metal bits stick to the FD magnet, then it's a warning sign for the crownwheel bearing is about to end it's work contract
Ride safe, Margus
Last edited by Margus; 27 Aug 2008 at 13:37.