You want to boost engine performance a bit? There's no replacement for displacement, so why not get this Airsal Cylinder 165cc Alu SYM Euro MX 125cc 4-stroke. It is an aluminium cylinder with bigger bore, meant to be used with the original cylinder head. The kit makes for slightly more power and definitely more torque. To be more specific, the difference will be mostly noticed in better acceleration, better take-offs and slightly higher top speed.. Aluminium cylinders show significantly higher thermal conductivity than cast iron cylinders this means they can withstand much higher performances, plus it makes them less susceptible to piston seizure. ΣυμβατότηταDjango 125cc 4-stroke carb.Tweet 125ccAllo 125cc (after 2011) (AJ12W1-6)Euro MX 125cc 4-strokeJet 4 125cc (AD12W1-6)Jet V 125cc after 2012 (HM12VA-6)Symphony 125cc before 2012 (AY12W-T)Symphony SR 125cc after 2013 (AZ12W1-T)