I was wondering if anyone can help I have a piaggio typhoon running a malossi 172 bore 25mm carb and gear up kit and a pm tuning x-tech exhaust and since I've put the exhaust on the bike has lost abit of power and pm tuning claim it' gives a extra 2bhp which at the moment it hasn't done.. Can anyone tell me why it's done this and what else I need to do get this extra power like what jet I need etc ?.