Malossi 166 kit jetting

[klopp]

    Hello,  
Would really appreciate some advice I have got a PX125 Disc with a Malossi 166 kit and a road 2 exhaust which I put on but previously a sterling, Currently having problems when it gets above 45 MPH with the scooter becoming jerky. I am not sure if it is the jetting, I don't think it's fuel starvation put a new tap and correct length hose on this week,Have I made a mistake by taking the Sterling Exhaust off? It has a Dellorto 20/20 autolube carb and what I believe is the jets that came with the Malossi kit which the previous owner had installed. Am I using the correct carb? Concerned it could be some sort of seize, Quite a lot of compression starts and idles ok. Basically when riding the power drops and returns holds then drops again but riding upto 40 MPH its fine. Anyone else had or got a PX with the same set up as in 20/20 carb if so would like to know if the same issues were encountered and what jets I should be looking to use.
Cheers guys

[gpowell]

1. Was it running okay before you changed exhaust.
2. A SIP R2 exhaust will need different jetting to a Sterling expansion.
3. Strip carb and get jet sizes
4. Nothing wrong with 20mm carb

My first though is it rich on main jet due to the exhaust change, but it could be electrical.

Difficult to diagnose over the forum with little information.

[klopp]

Thanks for the reply seemed ok before the exhaust change but only rid it off road as it was sorn. Put the road 2 exhaust because the Sterling exit was spare wheel side it rode fine when it went for the journey to the M.O.T centre and back only about 12 miles round trip. I am going to have a proper look on my next days off work and possibly try the sterling exhaust again also check what jets are currently being used.