Most motorbikes use a chain to transmit power from the engine to the rear wheel. And it’s probably the part of your bike that needs the most regular maintenance.
If you don’t look after it with regular lubrication, cleaning and adjusting, it will wear out – fast! And that will cost you a load of cash, as well as possibly leaving you stranded if it snaps – or even damaging your bike irreparably. You can even risk serious injury if a slack or broken chain locks your back wheel or hits your leg at high speed.
Watch our tame bike journalists – Alan Dowds and Rob Hoyles – as they take us through the basics of chain maintenance. The guys look at lubrication, cleaning and adjusting, and show you how to check if your chain is at the end of its life.
How to lubricate your motorcycle drive chain
The most important part of regular chain maintenance is lubrication. The small metal bearing parts get a very tough life, stuck out in the rain, grit, dirt and muck of the road. It’s exposed to the elements, is spinning at high speeds, with massive torque running through it, and has nothing to protect it but a small layer of sticky chain lube.
So you should do that regularly, with a high-quality lube. Some people like to use a heavy gear oil instead – and that’s what bike firms often recommend, but a bespoke product from someone like the SDOC100 firm, Rock Oil or another bike specialist will do a better job of resisting fling, reducing corrosion and looking after the sealing ‘O’ rings. Whatever you use, little and often is a good plan, with a quick squirt after each ride, when the chain is warm, allowing the oils to penetrate and any lube-carrying solvent to evaporate. If the weather is bad or you’re doing very high mileages, then use a little more, but excessive lubing will just end up on the rear wheel, tail unit and number plate…
If you just did this, then you’d get a big build-up of dried lube all over the chain, and that can actually increase wear. Old lube mixes with road dirt to make a sort of grinding paste, which is nasty stuff. So you need to give the chain a regular cleaning too – either with paraffin or diesel and a soft brush, or a specialist chain cleaning product. Get the chain so you could eat your dinner off it, then let it dry and do your lubing as usual.
Adjusting your drive chain
The other part of the chain maintenance regime is adjustment. There’s a specific amount of slack which the chain needs to deal with suspension movement, and that will be printed on a sticker on the bike, usually near the chain or under the seat. Your owners’ manual or a local dealer can also help, and an internet search will also find the specified free play.
Measure the slack with a ruler, and do that at a few points along the chain run to check for any tight spots, where the chain has worn unevenly. If these are severe – if the chain is too loose at one point and too tight at another point – then the chain is worn out and needs replaced, along with the sprockets too.
If the chain is just a little slack though, it’s easy enough to adjust. There are a few different setups – single sided swingarms use an eccentric adjuster for example, but on most bikes, there are two adjuster bolts, one each side, with a locking nut on each. You need to loosen the rear axle nut so the rear wheel can move in the swingarm, and then loosen the adjuster bolt locknuts. Then, turn the adjuster bolts to move the swingarm backwards to tighten the chain, checking the tension as you go, and keeping track of how many turns you’re making. Do the same on the other side to keep the wheel in line, double check the tension, then tighten the rear axle nut with a torque wrench – and you’re done!