Crankshaft Euro 3/4 C.39.7 Derby Connecting rod 90mm RB Racing

Crankshaft C.39.7 connecting rod 90mm RB Racing for Derbi Euro 3/4.

The original crankshaft of the Derbi Euro 3 and Euro 4 is known for breaking the connecting rod when you start fitting high-displacement cylinders or demanding more from the engine than normal. This RB Racing crankshaft is built to withstand hard use without bending or breaking.

The 39.7-millimeter stroke and the 90 mm machined connecting rod allow the engine to rev out higher and handle high RPM ranges without vibrating like cast ones. With 1700 grams of weight, it has sufficient inertia for the engine to gain revs quickly, without losing strength throughout the entire RPM range.

If you are installing a 70cc cylinder or larger and want the crankshaft not to be the weak point, this is the part you need to keep the engine running smoothly and enduring without seizing due to lack of reinforcement.

Technical characteristics

• Stroke: 39.7 mm
• Connecting rod: 90 mm (machined)
• Web: 77 mm
• Pin: 18 mm
• Weight: 1700 grams
• Manufacturer: RB Racing
• Engines: Derbi Euro 3 / 4