The new Xtreme Racing crankshaft from Spanish manufacturers Airsal is a very high quality racing crankshaft at the level of Malossi MHR RHQ, Metrkit Pro Race or the Polini Evolution crankshaft. As the name suggests, the crank is designed to withstand extreme conditions and is only suitable with 10mm piston pins ie Airsal Xtreme 77cc / 70cc, MHR Team Malossi, Polini Evolution, Hebo Manston, Stage 6 Cylinders etc. The fully forged shaft 18NiCrMo5 high quality steel is hardened due to special heat treatment. The full cheek design allows higher pre-compression. The connecting rod is fully forged and hand polished to solidify the structure and has been subjected to the same hardening process as the crankshaft guaranteeing low wear in the bearings. A perfect, dynamically balanced crankshaft for heavy loads and optimum performance in high end engines. IMPORTANT NOTE: ONLY SUITABLE FOR USE WITH 10mm PISTON PINS