i have recently fitted a new leo vince tt exhaust system and blocked the other pipe which is no longer needed the bike will do no more than 16mph uphill but flat out down hill. what is going on and what can i do to get the maximum output from my new exhaust system? someone please help me....... my bike is a gilera dna 50 2001
the problem is your engine needs more back pressure to make it run right and the new pipe is the cause,an expansion chamber exhaust lets the gas run so freely that the back pressure doesnt exhist below about 5000 rpm ,the cure is to fit some 4-5 gram variator rollers to the variator it will rev alot more when you go to pull away and therefore the back pressure will be enough to make your 2 stroke engine work as it should.rollers are very cheap about £10 for a set of 6 ok hope you happy now you know what the prob is.
adam bike doctor
March 2009
Automatic Answer
While you wait for answers, we may have found some information which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix motorcycles.