Consistent maintenance will increase the life of a final drive chain, but eventually you’ll need to replace it.
To get the most out of a drive chain, you must regularly lubricate and adjust it. However, even the most meticulously maintained chain will eventually need replacing. There are a few signs to look for that will tell you when it’s time.
A noisy chain might quiet down once lubricated, but that rattling or grinding sound means the rollers are loose on the pins, and it may be time for a new one. Also look for rust-coloured powder around the pins, which indicates that the factory-installed lubrication within the rollers is long gone and the chain has started to corrode from the inside; it’s definitely time to chuck it in the recycling bin.
A chain whose adjustment varies greatly in different positions as the wheel is rotated means it’s not evenly stretched and is therefore due for replacement. Probably the easiest way to determine whether your chain is done is to pull it away from the rear sprocket: if you can get a gap between the chain and sprocket, well, you know the drill.
Many people say you should also change both sprockets at the same time you replace the chain, but I’m all for reducing waste (and I’m cheap), so if you don’t have a high-horsepower bike that puts high loads on the drivetrain, and you meticulously maintain your chain, it’s possible that the sprockets are still good. A worn sprocket will have irregular-shaped valleys and hooked or pointy teeth. In the case of my KLR650, which recently got its first replacement chain with 22,000 km on the odometer, the sprockets were like new, so they stayed on the bike.
Before taking on the task of replacing a drive chain, you should first make sure you have the proper tools. You’ll need a chain press (about $75), a chain puller (about $25), and possibly either a bench or a hand-held grinder.
With these tools at hand, you should then determine how many links your chain has. This can be found in the owner’s manual or service manual, or you can count the links and multiply by two, because even though chain length is counted in links, we are really talking about the pins.
I prefer counting the links, in case a previous owner altered the gearing by increasing or reducing the sprocket size. But be aware that a previous owner could have removed a link because the chain was stretched past its serviceable limit (which is a big no-no and should never be done). Bear in mind that most OEM chains are endless, so they don’t have an easily identifiable master link circlip to use as a starting point.
Chains are usually sold in pre-set lengths, so get a chain size that is closest to what you need, to save some money. My KLR has 106 links, so I bought a 110-link chain, which was then cut to size.
With the rear wheel raised off the ground, move it forward in its adjusters so you’ll be able to get the new, unstretched chain onto the sprockets. The next step is to break the chain. If there is a master link circlip, remove it with a pair of pliers and press out the master link with the chain breaker.
If it’s an endless chain, grind the pins flush on one of the links. This makes it easier to take the chain apart. Again, use the chain breaker to pull the link apart, which involves pressing the pins out of the link.
The above procedure is the same one you’d use to size your new chain – just make sure you included the master link when counting the pins before cutting the chain. Note that on the motorcycle, you should never punch the links out using the sprocket for support, or you risk bending the sprocket.
With the old chain now separated, use the pinned portion of the master link to attach the new chain to the old one. You can now thread the new chain around the front sprocket by pulling on the old chain. This should be done in the direction of wheel travel to ease the job.
With the new chain threaded onto the sprockets, pull it together onto the rear sprocket and assemble it using the master link; don’t forget the O-rings if it’s an O-ring chain. If lube is included, apply it liberally.
There might be two types of master link included with the chain: riveted and clip. Both will need to have the links pressed together with the press tool. On the clip type, press the link on just far enough to clear the clip grooves on the pin. Use a pair of pliers to slide the clip onto the pins, then use the chain breaker to press the pins back in just enough to put a bit of tension on the clip to help keep it on. The closed end of the clip should be installed facing the direction of travel, so that an obstacle can’t catch the open end and pop it off.
On a rivet-type master link, the pins are stepped, so you need only press the link until it stops on the shoulder of the pin – don’t force it farther. You can then use the riveting tool, which is part of the press tool, to rivet the pins.
Adjust the chain to the manufacturer’s specs, and don’t forget to readjust it after a short ride, because it will stretch considerably while breaking in.
Technical articles are written purely as reference only and your motorcycle may require different procedures. You should be mechanically inclined to carry out your own maintenance and we recommend you contact your mechanic prior to performing any type of work on your bike.
