Racing cylinder with 244 cc for the Vespa 200 models from VMC. The "Explorer" enables modern riding performance and balanced characteristics.
The VMC cylinder in the 200 class throws a whopping 244 cc with 60 mm stroke into the ring. This is made possible by the 72 mm bore. A concept that is already successful on the market, but rethought by VMC.
- Powerful
- High torque
- Suitable for everyday use
The VMC Explorer has an exceptional and well-functioning overflow system. The four lateral overflow channels have a very bulbous design. They are supported by three boost ports, of which the two outer ones are more a mixture of boost port and overflow channel. A good idea to compensate for the limited space between the studs.
The performance characteristics
The cylinder shows itself to be powerful. More important is the very wide power band and the high torque. Especially in the lower rev ranges, the cylinder pulls through very well. Even with a resonance exhaust, the power gap before the exhaust resonance is hardly noticeable.
Plug and Play?
Of course, such a high-displacement cylinder with such an effective overflow system cannot be easily accommodated on a small Vespa engine. However, VMC has come up with ways and means to make the cylinder compatible with original parts.
The contour of the overflow towards the sealing surface is such that it always leaves enough space for the gasket on the original casing. There are contours that can be easily removed if more sealing surface is available.
On the ignition side, the channel has a sprue on the inside. This narrows the cross-section of the channel, but allows the cylinder to be machined from the outside so that it can be combined with any flywheel. If a flywheel is used that leaves sufficient space, the sprue inside the channel can be removed easily and quickly with a milling cutter.
The cylinder has a small cylinder base that gives the piston approx. 7 mm of additional guidance. Extra space must be made in the crankcase for this, because the small cylinder foot is larger in diameter than the standard hole in the crankcase. This work can be done by a specialist workshop. However, VMC also provides the means to carry out the adjustment with "home remedies". The kit includes a steel stencil along which the casing can be cut to the correct size with a milling cutter.
Crankshaft
The VMC 244 Explorer is designed to use a conrod with a minimum length of 126 mm. The long conrod provides smooth running and allows plenty of room for the over-current system. The piston with two 1 mm rings is provided with large recesses through which the gas can flow into the channels.
Bolted exhaust and cylinder head
The exhaust is made of steel and is screwed to a plate. Stable seating for exhaust springs is integrated into the plate. The cylinder head with central spark plug is even secured with eight screws. Both, head and exhaust, are sealed with o-rings.
Technical details
- Aluminium-Nikasil cylinder
- 72 mm Bore
- 60 mm Stroke
- 126/127 mm Connecting rod length
- 7 Overflow
- Oval exhaust
- 8-bolt cylinder head
- Bolted steel exhaust
- O-ring gaskets
- 2 x 1 mm piston rings
- Central spark plug
- Cylinder base 76 mm x 8 mm
Conclusion: A very innovative cylinder with not only the best performance values, but also excellent all-round qualities.
For this cylinder we recommend - SIP TIP:
