Motorcycle Heavy Duty Solid Bush Chain 520-112 LinkCHU520112 Motorcycle Heavy Duty Solid Bush Chain 520 112 Link Triple S Heavy Duty Solid Bush chains are an upgrade to Standard and Heavy Duty chains. Heavy Duty Solid Bush chains utilise a solid bushing inside the roller instead of the split bushing used in Standard and Heavy Duty chains. This solid bush increases wear and resistance and minimises chain elongation, consequently Heavy Duty Solid Bush chains last 50% longer than equivalent Standard and