Rapido Kits

The History

The Rapido has been available since January 2001. The First kit available was the Race Rapido 200cc. This guise of the Rapido showed the potential available from this design of the cylinder and was quickly followed by the over bore Race Rapido 225cc. The performance offered by these two kits meant that they were best suited to road race bikes with uprated engine components, full-blown expansion systems and open carb set-ups.

It was then decided that an intermediate kit should be offered. The Classic Rapido was introduced one year after its older brothers. It’s specification designed to cater for people who wanted to keep the classic good looks of their Lambretta using the original carburettor and silencer system enhancing reliability through the improved cooling of the rapido design, with a little extra speed.

The Final Development of the Rapido Cylinder has been the Race Rapido 250cc. Arthur Francis was the first person to develop the 250 using Bultaco and Montessa parts but the conversion could never be offered to the customer because of the complicated procedure required to adapt the conversion to the Lambretta.

Ray developed a simplified 250cc conversion in 1984 which dominated the racing scene at that time. This kit was offered to customers but had long term reliability problems caused by the cast iron cylinder being unable to dissipate the heat efficiently.

The success of the Race Rapido 200cc / 225cc kits instigated the further development of the rapido cylinders creating the latest Race Rapido 250cc.

The Rapido 250cc kit has been available since January 2004.

The Technology

The Rapido Cylinders success is down to clever use of materials and an exceptional manufacturing process, combined with an in-depth knowledge of performance tuning the Lambretta engine for Race and Fast Road use.

The Rapido cylinders are made up of two parts, a liner and a cooling jacket. The Liner is made of steel and has been cast to protrude in to each of the ports to the gasket face, this means that in effect the liner could be fitted to an engine and run as it is. To provide the cooling for this liner, an aluminium jacket with cooling fins is cast around it. This means that there is no chance of leakage between the liner and the jacket, and all the benefit of the heat dissipation properties of Aluminium.

The Kits

Classic Rapido 200cc

The Classic Rapido 200cc Kit is made up of a 66mm cylinder, a three ring Mahle piston kit and a top end gasket set.

This kit is intended to be a direct replacement for a standard 200cc top end. Offering improved performance and increased reliability whilst being compatible with a standard exhaust and carburettor. The kit benefits from the addition of other performance products (ie expansion chambers and open carburettors) but they are not essential. This kit can also be tuned to the same specification as the Race Rapido 200cc / 225cc at a later date if desired.

Race Rapido 200cc

The Race Rapido 200cc Kit is made up of a 66mm cylinder, a two ring Asso Werke piston kit and a top end gasket set. An alternative Mahle piston is available at £10 less.

The 200cc variant offers the smoothest power delivery with least vibration allowing the engine to rev freely.

Race Rapido 225cc

The Race Rapido 225cc Kit is made up of a 70mm cylinder, a two ring Asso Werke piston kit and a top end gasket set. An alternative Mahle piston is available at £10 less.

This kit is intended to be fitted with a performance expansion system and an open carburettor and its state of tune reflects this. Due to the power output and high rpm offered by this kit it is strongly recommended that a race crank is also fitted. The original cylinder head has to be opened out to suit the larger bore, or a new 225 cylinder head can be purchased for £27.50

The 225cc variant offers greater torque than the 200cc allowing it to pull out of corners and off the line with a little more grunt.

Race Rapido 250cc

The Race Rapido 250cc Kit is made up of a 72mm cylinder, a forged two ring Asso Werke piston kit and a top end gasket set.

This kit is the top of the range. It requires a 60mm Road Race Crankshaft and modification to the neck of the crankcase to accomodate the increase in neck diameter of the cylinder. The original cylinder head has to be opened out to suit the larger bore.

This kit requires an expansion system designed for torque instead of high rpm (suitable expansions: Fresco, Taffspeed, JL etc.). The minimum carburettor size recommended is 32mm.