I'm new to snowmobiling but I've been around cars and motorcycles all my life. Yesterday I picked up a 77 Polaris TX twin cylinder. I cleaned out all the old fuel, changed the fuel lines, throttle cable and spark plugs and managed to get the engine running, though not perfectly. The track spins ok in the air, and on garage floor with no on the sled, but when I took it outside and tried to go, it just seemed to rev. I figure if it was a traction problem, it should at least be throwing snow out behind it, but it doesn't seem to. With some pushing I managed to get it going down the road but as soon as I slowed down and tried to turn around, I got caught up in the edge of the snowbank and lost my drive again. Then it stalled and would not start again. We brought it back on the truck and managed to get it started again but still had no drive. I think I can sort out the carb problems but I don't know where to start with the drive system. The track looks to be in good shape. Can somebody please help? [/font=Comic Sans MS]