With rotax engine it runs like the choke is on all the time on low revs i have had the carb in bits and adj the needle settings as the revs pick up it runs ok and starts great all the time .could it be the reed valve or a worn needle i can get it to run not bad untill the bike starts moving then awfull again any help please

Have you checked the rubber between the airbox and carb? I was told when I had one of these beasts it was a common problem for these to crack! I may even have a good one kicking about in the garage if this is the problem.

Have you checked the rubber between the airbox and carb? I was told when I had one of these beasts it was a common problem for these to crack! I may even have a good one kicking about in the garage if this is the problem.

Thanks for the info will check it out and let you know how i go on many thanks