heres mark, the guy who built and travelled to bonneville making the kr1s the official fastest production 250 in the world. aswell as been a handy club racer he is also a very good tuner and has built the fastest f250 in the country. have got lots of tuning info from his in refference to the kr1/s over the years. a sound bloke who looks like a proffesor.this is the bike paul has, he took one bike but a few motors in different states of tune. i think to be eligible, the motor has to remain std albeit blue printed.