I have a super z with the 37 kawi with approx 80 hrs on it. When the engine is cold it will not start. It is at the dealers for over 5 weeks now, the starter was swapped, the valves adjusted, new battery etc. When you try to start it the machine will backfire so loud you need to cover your ears when turning it over. I am very frustrated with the whole thing and want nothing to do with this motor, I love the machine though. Am I wrong in demanding a new engine and has anybody ever had a machine stuck at a dealer for five plus weeks? I am glad I found this site very informative.