found this on the net

This procedure is by no means obvious. After putting in many hours of research, here is the method of coding that I find works on my heritage (MT2500).

P2336 cylinder 1 knock threshold exceeded = read as injector 1 so code cylinder 1
P2337 cylinder 2 knock threshold exceeded = read as injector 2 so code cylinder 3
P2338 cylinder 3 knock threshold exceeded = read as injector 3 so code cylinder 4
P2339 cylinder 4 knock threshold exceeded = read as injector 4 so code cylinder 2