This past week we were riding in Indian River and my 2001 MXZ 600 began to bog and fouled the clutch side plug twice. I narrowed it down to the plug wire. Luckily I was near SPANKYS and bought a replacement boot. The boot is the hard plastic type. The machine ran like a top after the switch out. I was wondering are the wires on this machine replaceable or do I have to replace the whole coil? Also, has anyone changed to the hard plastic from the soft rubber and thought they were better.