Crankshaft Derbi Variant Start 5 C.42 connecting rod 85 RB Racing

Crankshaft C.42 85 connecting rod RB Racing for Derbi Variant Start 5.

If you are looking to get the very most out of your Derbi Variant Start 5 engine, this RB Racing Crankshaft is the component that will make the difference in your racing build. This is serious hardware: a high-performance crankshaft manufactured to withstand the stress of the most demanding cylinders on the market.

The first thing that stands out is its 42 mm stroke configuration combined with an 85 mm machined connecting rod made from a forged block. By fitting this 85 mm connecting rod, we reduce the piston’s angle of inclination, which drastically decreases lateral friction against the cylinder liner. This results in an engine that revs more freely, reduces wear, and pulls with brutal force at high rpm.

With webs measuring 74 mm in diameter, this crankshaft increases pre-compression in the crankcase, achieving excellent gas charging speed. Keep in mind that, with a web diameter of 74 mm, it is necessary to bore or mill the original crankcases of your Derbi Variant Start 5. Its weight of 1335 grams is perfectly calculated to provide the necessary inertia on the track, stabilizing the engine at high rpm.

Technical specifications

• Stroke: 42 mm
• Connecting rod length: 85 mm (machined)
• Web diameter: 74 mm
• Total weight: 1335 grams