The complete MR NINJA engine line was born from an absolute new and high-tech industrial project, realized in Italy by GRP, under the technological supervision of Mario ROSSI.

Thanks to the technological and futuristic research centre at GRP, the very first projects were realized, and it will allow a continuous future product development. Everything has been studied with the most up-to-date and advanced software of mechanical simulation, to know and reproduce the conditions of use and deformation of components and materials at high temperatures.

All components (even the ones apparently less important) have been meticulously studied and the result has confirmed a very high basic quality that will set a new worldwide standard quality in this field.

The look and packaging for mechanical components which are normally neglected, have been studied here in details to guarantee a truly complete product. Each single engine is delivered with protection cover for exhaust, intake fuel entrance and carburetor. It will come with a manual of use and maintenance and a spare parts catalogue on CD, written in five languages.

APS is an exclusive treatment studied after many tests that can be applied on different components such as rear cover etc. These pieces are wear resistant and they guarantee a reduction of loss of friction and therefore power.

TCS is a technical concept for the separation of direct contact of carburetor body with crankshaft, to control the temperature of the carburetor itself. An insulating bush made with a very special mineral material interrupts the heating passage to the carburetor body, guaranteeing a better regulation of the carburetor functioning. In this way, the carburetor body can be made entirely with an aluminium alloy to guarantee maximum regularity at any temperature of use.

It is designed with a special profile through which we can obtain the perfect balancing of the piece, without having to balance it up with some weights, which generally creates heterogeneous deformations at temperatures of use.

It has been studied with the most developed and advanced software of mechanical simulation, to simulate all deformations at high temperatures of use. Therefore, we managed to create a very stiff structure, mainly in the area of cylinder/exhaust and carburetor joint/intake. The manifold joint is fixed with 4 identical springs, which are perfectly fitted between the cooling fins. The special aluminium alloy used for the press fusion process, combined with the patent system for port production are extremely important.

The rear cover is made with ergal and then it undergoes an APS treatment. It is resistant to abrasion, due to conrod rotation, and it also guarantees contemporaneously a reduction of loss of friction and therefore power.

The rod is produced with a special advanced technological material, which has allowed the exclusion of any bushings. This gives a greater lightness, leading to a higher acceleration and rotational rate. Moreover, this material has a specific heat resistance at high temperatures of use guaranteeing a minimal deformation.

The piston has a particular design and it is made directly from a “cnc” production, using a special aluminium alloy, which guarantees a very high dimensional stability at high temperatures, a very high wear resistance and it gives easy running and lower friction.

This sleeve is made with a special ABC alloy, but the main technical and mechanical characteristics are gained after special internal treatments, which guarantee a very high hardness and a notable wear-resistance. All external surfaces are trued to assure the highest dimensional quality.

It is made from a single piece of an Aluminium alloy, through a press fusion process. The Intake fuel body is entirely made of ergal for greater lightness and stiffness. All O-rings are made with a special material to guarantee the highest elasticity and resistance to fuel. All carburetors are supplied with a TCS insulating bush.

Carb Needle settings are default after breakin.

TIMING DIAGRAM HERE