This Airsal 120cc kit is probably the best value for money kit currently available!

One of the major key differences with this kit is its aluminium cylinder construction, against virtually all other cylinder kits currently available which are made from cast iron. The advantage of aluminium is a superior ability to dissipate heat. As most cylinder kits use an piston constructed from aluminium with a cylinder construction from cast iron, this presents the issue of combustion heat causing the piston expand at a faster rate than the cylinder, leading to piston seizure if the engine is run too hot. The matched aluminium construction of the piston and cylinder in this kit make it far less prone to piston seizure.

To add to all the above, this kit also comes with the head – where other kits do not.