Combines roller chain and sprockets

If possible, run a new identical chain for an hour or so. This removes all the preservative grease from the pins and bushes. Place new and old chain side by side, laid out straight on a flat surface. Compare amount of stretch and side ways bending between chains. Amount of wear becomes obvious. Always replace chains too early rather than too late. Chain is very cheap compared to sprockets. Don't put new chain on badly worn sprockets. It will destroy the chain in hours. If used, type of chain oil is critical. After trying dozens of chain oils, we found only one which was any good. We took a heavily overloaded duplex 1' pitch drive chain, on a specialised pasture seeds harvester, designed for 40 hp, running at 80 hp, and in heavy dust conditions, from a 200 hr life to a 600hr life just with the right oil applied once a day at work knock off and left overnight . The sprockets lasted some thousands of hours. Sadly, the oil, made by a very small outfit, is no longer available! Heavy used diesel oil, with its high carbon content, is as good a lubricant as a lot of chain oils. Makes a shocking mess though. Cheers!

I've been using chainsaw bar oil for a long time as it seems to work well and is cheap. Works best when applied like ROM says when chain is warm or after working . Did'nt like sump oil at all cause of mess and acid eating paint work etc. Dont use any oil on our hay balers chains cause we found they would wear out twice as quick when oiled . Any more than 10% stretch when compared to new one like ROM says ,Bin it !

I save my tranmission fluid out of my tractors and mix about 1_4 diesel fuel with it along with 2 oz. of heavy duty Wynns oil, which is an anti friction oil additive per gallon. I put in an old Hudson pump up sprayer and open the nozzle to get a steady stream and apply it to chains while machine is running. The long wand makes it easy to get into tight places without having to get to close to a running machine. If you pump it up enough you can really stand back as long as you don't care if the machine gets a little messy. Just blows off with air when season is over.