The rotary vane intake manifolds for the small frame engines offer the possibility to use carburettors up to 24mm. This allows to realize quite powerful engines, which can easily reach the 120kmh mark. To enable the full performance potential of the engine, the engine housing should always be adapted to the cross-section of the carburetor (as far as possible). Whether a larger carburettor and thus a larger intake manifold is necessary at all, depends on the displacement and the speed at which the full power should be delivered. A 133ccm cylinder (e.g. Polini) with a nominal speed of 7000 rpm is very well served with a carburettor cross section of 24mm. Using larger carburetor diameters on such an engine does not increase the power output at all and, apart from the engine's efficiency, it also usually worsens the tunability. It only makes sense to use larger carburettors if the engine delivers its full power only at a higher rpm (not to be confused with the maximum rpm the engine can reach in third gear!) As an example, the 136cc Malossi is the only one to be mentioned here. This one is already driven with the direct intake kit with a 25mm cross section. With a suitable exhaust and other remaining design of the engine, this cylinder can also make good use of carburettors up to 30mm. Intake manifolds for such extreme tuning variants are offered by us in long version by Zirri. With these intake manifolds the carburettor is still in its original position.
AI-translation
DE | €
