Exhaust Flange Yasuni Cross HM

YASUNI Cross HM

The Spanish brand was originally known in MotoGP, when two-strokes dominated the discipline. However, Yasuni has now also gained an excellent reputation for their exhausts for 50cc supermotos, which includes the Yasuni Cross HM.

The "Cross" exhaust from Yasuni is a high-mount exhaust. The ML is the racing version of the Cross.

PERFORMANCE YASUNI cross HM

The Yasuni Cross is powerful and high-torque, especially in the medium and high RPM range. It is primarily intended for 50cc to 70cc sport and racing cylinders.

To fully utilize the performance of the Yasuni Cross HM, we recommend using a 19 - 24mm carburetor and a reinforced clutch to prevent clutch slipping during off the line acceleration.

If you absolutely want a Yasuni exhaust, but have a setup with a very large displacement or very high power, you should opt for the low-mount tuning exhausts from Yasuni: Yasuni R2, R3, R4...

Exhaust flange

The exhaust flange provides a stable, sealed and separable connection between the exhaust and the engine.

Function of the exhaust flange

Depending on the engine type, the exhaust flange is attached to the cylinder by means of bolts or by press-fitting. It is then fitted into the exhaust pipe and held in position by two exhaust springs, thus maintaining a certain flexibility. To ensure tightness, there is normally an exhaust gasket. Thus, the flange provides a secure and at the same time flexible connection between the cylinder and the exhaust.

And what is an exhaust restrictor?

Many 50cc scooters and motorcycles are factory equipped with an exhaust / manifold restrictor. This restriction reduces the diameter of the exhaust flange, which restricts the performance of the exhaust. This restriction was introduced to comply with noise emission regulations and to limit the speed of 50cc scooters and motorcycles.

Many riders remove this restriction to improve the performance of their two-wheeler. However, the gain in power then leads to the loss of the homologation, so beware!