High-end Crankshaft with 60 mm stroke for Vespa T5 Model Engines.
The Crankshaft, together with the Cylinder, forms the heart of every Engine. It is one of the most heavily stressed parts. The conversion from stroke to rotary motion places the highest demands on quality and workmanship. The Shaft should also be well balanced to reduce vibrations. The oscillating masses should be low to support the performance of the Engine.
- 60 mm stroke
- 115 mm Conrod
- Balanced intake timing
The lower connecting rod bearing rotates at engine speed, is lubricated by the two-stroke mixture and must absorb the load of the Piston's change of direction twice with each revolution. The Crankpin, which connects the two crank webs and the Conrod, must be compressed to exactly the right degree. If the pressure is too low, the crank webs will twist in relation to each other. To ensure that sufficient mixture reaches the lower connecting rod bearing for lubrication, the lower connecting rod eye should be provided with lubrication slots.
The SIP Crankshafts
The new Crankshaft line from SIP is manufactured in Italy and meets all these requirements. Particular attention has been paid to the highest quality and sophisticated design features. The balancing of each Crankshaft is adapted to the stroke, connecting rod length and scooter model. An extremely high-quality polished Conrod is used in the "Performance" shafts. Polishing refines the surface. This means that it becomes denser and has a more stable structure, which makes the Conrod more resistant. The polished surface also ensures less turbulence. The polished Conrods are further weight-optimized. Their lateral contour is more aerodynamically shaped and they are reworked in the area of the lower bearing for even better cooling of the connecting rod bearing.
The 60 mm T5 Crankshaft
This Crankshaft was specially developed for extreme conversions based on the T5 Engine. In addition to the unusually long stroke for this Model, the Shaft has an unusually long 115 mm Conrod. This not only promotes smooth running, it should also make it easier to adapt cylinders from other manufacturers to the stroke. A 16x20x23mm Gudgeon Pin Bearing is supplied. This fits both the pistons of the Malossi cylinders and other pistons with a larger bore.
Note: The Crankshaft cannot be easily installed in conjunction with conventional T5 tuning cylinders. Stroke and connecting rod length require compensation or adaptation of the Cylinder, e.g. by welding.
The Crankshaft casing does not need to be spindled.
When installing in original casings, some space must be created at the upper edges of the crankcase for the Conrod. This can easily be done with a Dremel, for example.
Conclusion: The ideal Crankshaft to take T5 Engines to the next level. Only for experienced tuners.
The best setup - our SIP-TIP: