rotax max is the same engine as an aprilia rs 125 without the gearbox but has an adjustable power band valve its clutched and has electric start
its 2stroke and goes like shit of a shovel set up properly will do 0-60 in under 4 secs
and between 60 and 85/90mph depends on rear cog they are great fun and prob the best to start on!
got one if your after one also a kx 80cc shifter and a tkm 100cc with loads of spares