Description
Racing crankshaft 2Fast Minarelli horizontal / Aerox
Crankshaft 39.3mm stroke / 85mm connecting rod 2Fast Minarelli horizontal, high-end racing crankshaft for demanding tuners from the Italian tuning company 2Fast, specially designed for 70cc setups.
This crankshaft was developed specifically for the 2Fast 70cc cylinder and guarantees top performance in that setup. It can of course also be used with other racing cylinders with matching stroke.
The crankshaft has 39.3mm stroke (original) and an 85mm connecting rod.
With a different small end bearing (17mm outer diameter), cylinders with 13mm or 14mm piston pins can also be fitted.
Note: the crankcase must be slightly machined so that the crankshaft and crank webs fit. Web diameter is 75mm.
Technical information 2Fast Racing crankshaft
- For Minarelli horizontal - Yamaha Aerox etc.
- Stroke 39.3mm (original)
- Connecting rod 85mm - crankpin 18mm
- Small end bearing 12x17x16mm
- Crankcase machining required
- Weight 1470g
How to change a crankshaft?
The crankshaft is one of the main components of the engine and is responsible for the smooth operation of motorcycle, scooter and moped, whether with two-stroke or four-stroke engine. The longevity of the engine depends not only on the proper condition of the crankshaft, but also on the fact that it is properly mounted.
For a correct installation of the crankshaft, we recommend our tutorial: Crankshaft disassembly and assembly.
How can I tell if my crankshaft is Damaged?
A broken crankshaft causes metallic noises, unusual vibrations, leaking oil seals and drastically reduces the performance of the two-wheeler. In any case, the vehicle must be stopped immediately to prevent the damage from getting worse.
Please note that whenever the crankshaft is changed and serviced, you'll have to install new crankshaft bearings.

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.
Crankshaft 2Fast 39,3mm / 85mm Yamaha Aerox | |
---|---|
Article no. | TFAST084 |
Weight | 1,80 kg |
Brand | 2Fast |
Product type | Crankshaft |
Tuning level | High-end |
Piston pin | 12 mm, 13 mm |
Needle bearing | 12x17x16mm |
Stroke | Original |
Conrod length | 85 mm |