Motorcycle parts-rock arm:Material: 20cpm°
1.Surface hardness: 78°-°HRA<Rockwell> Strengthern wear resistance
2.Core hardness: 25°-30° HRC using advanced technology of vacuum net bag stove and fitting with appearance hardness.
3.Chrome plated layer: 30-45um, reaching wear resistance strength
4.Product features: The product is based on international sandards and in accordance with Japaneese technical requiements in the assembling of engine for motorcycle. 
5.It is passed inspection of Tianjin Research Institute for Internal-combussion Engine an is an auxiliary product for Dachangjiang, Yibao and Shanghai Yizu.