Aerox 50cc with exaust for 70cc

I have yamaha aerox 50cc cylinder, but the exhaust is Gianelli shot that was intended for The cylinder for 70cc .. Can someone suggest me some solution, because my problem is in very bad acceleration and a bad start. End speed is great ..
(over 80 km/h)
Does anyone have experience with standard aerox 50cc and 70cc exhaust Gianelli shot?
Acceleration is poor, and the uphill is very slow (20-30 km/h). I think the problem is in rapidly changing gear, that lose power ..

Do i need to change variator, rolls, clutch or something?

Please tell me exactly what i need to change





Image no longer available

First of all upjet your carb by 10% that's from a 62 to a 68 if you've got the standard 12mm carb.
If you've got the standard Aerox variator ditch it and buy a Malossi or Pollini and drop the roller weights , try 5g as a start.
Should be okay then.

Thanks

i solve my problem, hope this will help someone else too... i change clutch springs too hard one... so just change spring on clutch to harder,
now is great, i am very satisfied