505/3BX 3 speed manual MLM 21mm OKO Thunderpower Power Jet 80cc Athena Reed Valve Boyesen Reeds Kevlar Clutch Skid stops all day. Trans needs to be fiddled with this winter but it's fun. I highly recommend thunderpower power jets. They can take you all the way from over heating to four stroking and very fine adjustment inbetween. Awesome addition.