My wife's sled is a 1992 Indy 500. I just replaced the plugs and coil, and it's running really nice, with one exception. We went out this weekend, and when we stopped for gas, when I went to pull start it, the rope became loose and it wouldn't engage. When the sled sat for a while and cooled down, everything was fine. When we got home, same thing - sled was warm and the rope was loose and wouldn't engage, but the next morning it was fine. Is this a clutch issue, or something worn in the starter? I just want an idea before I start tearing things apart.