Hi Jewel,
 Have only had a race one so can not comment apart fom that they can blow a head gasket ocassionly. 
 Having owned on the road & then raced for three years sold it & then it has been raced for another two years with out the motor being opened or tuned is a NC29 Gullarm, damn well bullit proof, nice bike to ride,& race.  
 Chris.
