07/09/2017 10:19am
What makes a chain break?
Well, the first thing to realise is that breakages are now extremely rare!
Modern chains are manufactured in fully automated, computer controlled factories and the quality of these products is truly amazing. Just think a 500cc racing single in the early fifty’s would be putting out around 50BHP and would be running a 530 pitch drive chain. A modern 1000cc top flight race bike can put out approaching 250BHP and is running a thinner section 520 pitch chain. That’s 250bhp being transmitted through chain rollers and sprockets just ¼ ‘’ wide! Even a production 1000cc bike is now rapidly closing on 200BHP so modern chain technology is simply amazing. As long as the chain is manufactured by one of the major producers it is unlikely to suffer from any production faults. So what makes them break?
Firstly, make sure you buy the correct grade of chain for your model. It is no good buying a chain meant for a road going 125 and then fitting it to a 1000cc superbike! After that, it mainly comes down to lack of maintenance and incorrect fitting. This can be due to poor lubrication, incorrect tensioning, incorrect alignment, poor fitting of the joining link and occasionally chemical or debris interference such as battery acid attacking the O and X rings or road debris getting jammed between the chains and sprockets.
Most common amongst all of these is poor lubrication and incorrect fitting of the joining link.
Despite all the information, instruction and advice to the contrary joining links are still sometimes fitted with little or no lubrication and are over tightened. This causes a condition we call ‘hot point’. Basically, the lack of lubrication and over tightening causes the chain link to get hotter and hotter. This, in turn, causes the steel to become too brittle and ultimately the link fails due to metal fatigue. To avoid this happening, follow the advice shown for lubrication and fitting of the joining links. Then keep the chain correctly tensioned and aligned and the chances of your chain breaking are reduced by about 99%. Happy days!