Clutch Pinion 24 Teeth Helical DRT For Primary 65 Teeth Vespa 12

The gear shifter drives the clutch assembly main gear shifter to the input shaft in the large VESPA engine frame. By varying the size or number of teeth in this gear, you can change the main gear ratio of your engine. Changing the clutch gear is the easiest and quickest way to change the overall gear ratio of your engine. The more teeth the clutch gear gear has, the larger the gear teeth.

The clutch gears for the II COSA clutch are available with 20, 21, 22 and 23 teeth. The gears with 20 or 22 teeth fit in 125-150cc engines and the 21 or 23 toothed gears in the 200cc engine without having to also replace the primary gear sprocket. If, however, the primary gear drive gear is also replaced, all clutch gears can be used with both engine sizes. The primary gear driven gear in the 200cc engine with 65 teeth can be combined with 21 or 22 toothed gears, together with the original element with 23 teeth. The most popular clutch gear conversion gear is the version with 22 teeth, thus allowing improved acceleration through the gears, without expensive tuning measures, especially between the 3rd and 4th gears. For VESPA T5 engines equipped with the MALOSSI 172cc cylinder kit, a clutch gear with 21 or 22 teeth has proven to be suitable. If the driven main gear with 65 teeth (from the 200cc engine) is used in a 125-150cc engine, the 200 clutch gear can also be used in the smaller engine.

DRT have also managed to fill the gaps in the number of gear teeth available for the COSA PIAGGIO II clutch gears. DRT produces clutch gear gears to suit all sizes of primary gear. A significantly quieter and more durable drivetrain is the result. This also extends the overall life of the gearbox and therefore the engine and also improves the efficiency of the transmission, with more power reaching the rear wheel. The straight cut gear gear with 22 or 24 teeth are designed for use with the POLINI driven primary gear gear. The primary gear ratio of 2.67 resulting from the gear tooth ratio of 24 teeth on the clutch gear sprocket and 64 teeth on the driven primary gear is the highest conversion primary gear ratio available for the II COSA clutch apart from the Worb5 version of course... The clutch gear sprocket with 23 teeth produced by DRT matches perfectly with the PIAGGIO OE driven primary drive sprocket in 125-150cc engines with 67 toothed gears and 68 toothed gears, respectively.

Helpful Hint: All large models as the VESPA VNA / VNB frame range up to 1994 can be equipped with the COSA II clutch. With these 125-150cc models the existing clutch cover must be modified due to the larger size of the COSA II clutch conversion, or replaced with the clutch cover from the 200cc engine and a suitable pressure plate. For this reason they have been included in the accompanying lists.

Conclusion: A suitable transmission is available for every model included in the accompanying lists.

Don't forget to order a new clutch holding nut, lock washer, thrust plate and pump. New clutch friction plates are also recommended when doing this job. With different gear sizes on the input and output shafts even more experimentation with reduction ratio is possible. Wider section tires are also a popular way to raise the engine gearing.