Cylinder Kit Polini Big Evolution 70cc Yamaha Aerox / MBK Nitro

The kit includes:

70cc Aluminium Cylinder Evolution 2010 for 85mm conrod, with 6 transfer ports and bridged exhaust port
Single-Ring Piston, 12mm pin
High-Compression Monobloc Cylinder Head Evo 2010
Gasket Kit for mounting and adjusting squish clearance

Technically speaking, the Polini 70cc Cylinder Kit Evolution 2010 MBK Nitro / Aerox is a Nikasil-plated aluminium cylinder with 6 transfer ports and a divided, bridged exhaust port (new shape). It comes with a top quality one-ring piston (d = 47.9mm, 12mm piston pin) and a special monobloc cylinder head.

The design of the kit was revised, among of the redesigned features:
- the kit got a fresh look as the cylinder was cast using the same mould as the 94cc cylinder.
- the exhaust port exit is equipped with a triangular adapter plate held in place by 3 screws (your exhaust flange will be mounted on this plate)
- the high-compression cylinder head is cast from one piece and precision machined (with internal water passage and centering pins)

Quality of materials and workmanship of this cylinder kit are definitely top-of-the-line.

Note 1: The exhaust flange has a different angle than the original (Piaggio flat type) and can only be used with a Polini Big Evo exhaust (same series).

Note 2: This kit can only be mounted with crankshafts that have a 85mm connecting rod and a 12mm pin, and you'll have to mill the crankcase to make room for the cylinder base.