I'm gonna stop askin why people make movesets for krappy pokes, so I'll just give a little overview of Pinsir in RBY.
Learns swords. Fooz, he learns swords. Easily the second-most powerful move in the game, second to Amnesia.
Learns slash, fooz. Slash, arguably the best physical attack in the game, next to earthquake and body slam and drill peck.
Focus Energy. Oh hell yeah. They just keep getting better. Don't work to well with Swords, but still fun.
But let's face it, even with all these, Pinsir's moves aren't the greatest to choose from. These are great moves, but only individually. You can't have these three moves on the same poke, it would be ultimately stupid. They need to be used separately. However, let's see what else he learns that is worthwhile.
Bind and SD or bind and FE sounds good, and it will keep your enemy annoyed for a long time. Seismic Toss makes up for certain Pokes it'll have trouble with because of his lack of ability to learn any special attacks whatsoever and a dismal special at 208. Guillotine for gambling players. Body Slam, Double Edge for power, and same with Hyper Beam. But I hate Hyper Beam. Submission, even with recoil, does well SDed or FEed. He does learn DT. Rest, and that cleans up the only things that may be worthwhile on this thing, unless you like Substitute.
Swords Dance/Focus Energy, Submission/Body Slam, Double Team, Rest - this could work. Your choice of Crithits or superpower.
Slash, Hyper Beam, DT, Rest - meh.
Swords Dance, Bind, Slash, Submission - Shiz, with SD and Bind, why not?
Seismic toss, Hyper Beam, Slash, Submission - go for broke.
Well, if this is all I can think of, then really, Pinsir can't be that much fun.
Anything I say should never, under any circumstances, be taken seriously. If you really want to take it seriously, try and use your best discretion.