Racing Crankshaft 39.7mm – Bidalot RF50WR / AM6

This racing crankshaft with 39.7mm stroke is specifically designed to run with Ø40mm pistons on RF50WR engines. It also fits all AM6 engines, any year.

The 39.7mm stroke comes with a new forged connecting rod at 85mm center distance, CNC contoured on the outside to keep consistent wall thickness around the big end and small end. The crank pin is Ø18mm, and the big-end needle cage is made to dedicated specs, with free needles as on any true racing cage.

Technical specs:

• Crank webs machined from forged blanks
• Specific dynamic balancing
• Very precise crank pin to web press-fit
• Forged connecting rod, CNC contoured, 85mm center distance
• Crank pin Ø18mm
• Big-end silver needle cage, free needles, Ø18xØ24x11.8
• Small-end racing needle cage Ø12xØ17x15
• Bronze cellular side thrust washers
• Individual web grinding, allowing crankshaft rebuilding

Benefits:

• 📈 Reliability at high revs thanks to specific dynamic balancing
• 🛡️ Free-needle cage for better durability in racing use
• 🔧 Individually grindable webs for possible rebuilding
• ⚙️ Direct fit on Ø40mm pistons for RF50WR engines
• 🎯 Forged rod at 85mm center distance for precise power transfer

Note: this crankshaft fits all AM6 engines, any year.