A couple of thoughts...

The fun isn't in the speed...I know counter intuitive but that's typical of CK's!
Mark, feel free to have a go in mine, I'm sorry to say all it has is a tuned exhaust (to up the torque slightly) and the oil sensor disconnected, and despite that's all it's got is still manages to be rather sprightly.
Ian...as soon as a CK is moving it indeed has become hazardous.
Graham, given how difficult some of these tuned engines are for people to start, could we introduce Le Mans style starts?      Please