Xtr,xt,lx,stx,olivio.
There used to be a dx gruppo but shimamo dropped it early/mid 90's
The first issue of the rts bikes there was only the rts 1 and 2 the 1 was full m900 xtr. The rts2 was xt and lx both bikes had a 4130 chrome rear triangle.
After this the line up changed the team and rts 3 were introduced full xtr on the team (rock shock mag 21 sl ti forks I think I maybe wrong) and the rest of the bikes grouppos were changed eg rts1 was xt maybe xt/lx both USA made still,all these frames were full Ali Inc rear end not sure about the others,so I think by the end there were 4 rts models.
I may have a few things wrong but some one will make things clearer soon I hope!!!! Lol