Description
Exhaust Polini Evolution 70 Yamaha BWs
Exhaust Polini Evolution 2 70cc, very good racing exhaust from Polini for Minarelli vertical (Yamaha BW's / Slider, MBK Booster / Stunt). Without road approval, racing only!
Classic expansion chamber exhaust made of welded sheet metal with beautifully crafted black silencer (special 2010 version).
The exhaust was developed to fit the Polini 70cc aluminum cylinders of the Evolution series and is therefore considered a high-end exhaust, even if its performance level on Minarelli vertical engines places it more in the "Mid Race" range.
Very good results are also achieved with other Minarelli vertical cylinders - e.g. Malossi MHR Racing 70, Stage6 Racing 70, Top Performances TPR 70cc aluminum etc.
Exhaust scooter, moped, motorcycle
The exhaust has a major influence on the performance of scooters and mopeds. By replacing the original with a tuning exhaust, you can improve the gas flow and increase the engine power.
exhaust parts
- The headpipe or header is the connection between cylinder and exhaust, and an exhaust gasket provides the necessary seal. In street-legal systems, the headpipe is equipped with a legally required restriction. Some people remove this restrictor to increase power.
- The actual exhaust body or expansion chamber is connected to the header pipe. In a classic 2-stroke expansion chamber type exhaust, gas pressure waves are used to improve engine performance.
- At the end there us the silencer or muffler that discharges the exhaust gases and, with the help of damping wool, also reduces the noise generated by the vehicle.
Replacing the exhaust
As a general rule, please check if the exhausts fits BEFORE REMOVING THE RESTRICTOR, otherwise the exhaust cannot be returned.
For 2-stroke engines, various settings and components usually need to be adjusted when the original exhaust is replaced with a tuning version. These changes include:
- Adjusting the carburetor by replacing the main jet.
- Upgrading the clutch or replacing the clutch springs.
- For scooters, it may be necessary to reduce the weight of the variator weights.
Tuning Level: High End racing
We categorize our products into different performance levels Original, Sport, Racing and High End , so that our customers can choose the right parts for their setup. It is really important to combine parts that belong to the same tuning level, this is especially true for cylinders, crankshafts and exhausts.
High End Racing products are exclusively designed for racing and should only be handled by tuning pros with the appropriate technical know-how. High-end racing parts often require modifications or machining of certain elements to accommodate the often larger components (larger crank webs, larger intake, etc.). Whether you stick with 50cc or increase the displacement, high-end racing parts offer much higher performance than the original parts and are the most powerful tuning parts.
Note: To ensure the reliability of the engine, it is important that the parts are compatible and that you do regular maintenance on your two-wheeler.
