Tecno Streetline exhaust for 4-stroke scooters. The Portuguese manufacturer Tecno has adapted the internals to meet the needs of a small 4-stroke engine. As the 139QMB/A or GY6 50 have a relatively high valve overlap, the correct dynamic pressure is precisely the secret for optimum engine performance. Acceleration improves significantly and this helps increase power to a higher top speed. Currently one of the strongest assets of our product range. The sporty looks Suitable for very with the rear body shape. The exhaust is not restricted.