We have 1980, 1982, and a 1984 R65s, and the '80 has a kicker. I have been told they could be had on all of the bikes but were strictly special order. They are pretty much useless on the bigger bikes but I have started our '80 ONE TIME with the kicker - after it was warmed up. I have read BMW farkled up on the 5 speed kickers and they wear out /break very easy.
As far as sand coming out? I don't know what to tell you but it would make me very uneasy. You said, "...i had somestuff coming out of one of the cyclinders." Where did ot come out, out the exhaust port, muffler, where? If if coughed and blew some crap out of a muffler then maybe critters had built up in there, mud daubers, etc.