A motorbike chain is a vitally important bit of kit. It’s essentially the part that connects your motor to your back wheel, so careful maintenance is key to keeping your bike moving.
In this article we tell you everything you need to know about motorcycle chains, their cleaning, lubrication and how to install or remove. Also learn how to lube a motorcycle chain without a stand, and how to fit a Scottoiler.
How to remove a motorbike chain and sprocket
1. Get tooled-up
Motorbike chains and sprockets only have a limited lifespan. Fortunately, they are easy enough to replace at home if you have the right tools. Before you start, make sure you have a single hex socket large enough to fit the front sprocket retaining nut, the correct size sockets for the rear wheel spindle and rear sprocket retaining nuts, and of course a motorcycle chain splitter tool and riveter.
2. Count your teeth
When ordering replacement sprockets it’s important to get the correct part. Unless you’re changing the gearing, you should ensure that the new sprockets you buy have the same number of teeth as the originals. Deviating from the standard spec will change the final drive ratio, altering acceleration and mpg, as well as causing speedo inaccuracies.
3. Uncover the sprocket
First, remove the plastic front sprocket cover. This Suzuki SV650 only has three 4mm Allen bolts retaining the cover, but other bikes might also need the splined gear lever removed too. If this is the case, make a note or mark with a fibre pen the exact location of the splines in relation to the gear lever boss for reassembly.
4. Crack the nut
Loosen the front sprocket retaining nut using a single-hex, half-inch drive socket of an appropriate size. Keep an eye out for a locking tab washer behind the nut, this will need to be tapped back prior to undoing the nut. Because of the way it is torqued up, it will take a fair amount of leverage to undo the nut so you will need to use a breaker bar at this point.
5. Front teeth
Prior to fitting the new front sprocket, make sure the chain is slack by winding out the adjusters fully. Remove the sprocket and install the new one, put the tab washer on and make sure it’s lined up correctly on the spline. Tighten the nut up to the correct torque and bend the tab over one side.
6. Whip out the wheel
Remove the rear wheel then lay it flat on the floor using a protective mat or cloth to prevent damage. Undo the nuts that retain the rear sprocket, making sure to keep them safe for reinstallation later. Just like the front sprocket, make sure the new sprocket is the correct type and size.
7. Torque the nuts
Place the new sprocket on the mounting surface and tighten up the nuts by hand. If there are no locking tabs, all of the nuts should be the self-locking type. Tighten them up in a criss-cross sequence first, then use a torque wrench to torque them up to the correct value as listed in your workshop manual.
8. Split the chain
With the wheel back in, tighten the chain to prevent it twisting. Place the chain splitter on the soft link – this usually has a dimple on each of the rivet heads and will look different from the others. Making sure the splitter is closed-up on the back of the link, wind in the pin until it starts to press a link out. Then do the other side of the plate and push the other pin through.
9. Run in the new chain
Place the bike on a stand so the rear wheel can turn freely. Join the new chain to the old chain using the split link then pull out the old chain whilst feeding in the new chain until the new chain is around both front and rear sprockets. Remove the old link and chain, adjust the tensioners so that the chain can be joined.
10. Fitting O-rings
Rivet the side plates using your riveting tool. When pressing the side plates together, make sure any O-rings are in place and then evenly press the plates together with the tool. Keep an eye out on the amount of clearance and compression of the rings and be careful not to over compress them. Adjust the chain tension and torque up the wheel spindle nut.
How to adjust your motorbike chain tension
1. Get the back wheel off the ground
The drive chain on a bike is entirely responsible for transmitting the power from the engine and gearbox to the back wheel. A good maintenance routine will make it last longer and feel smoother. Part of that routine is making sure the chain is correctly tensioned. Do a visual check by putting the bike on centrestand or rear paddock stand, allowing you to turn the wheel and inspect the chain.
So why’s it so important?
Here is an example of an incorrectly adjusted chain. In this situation the chain would eventually start to run off the edge of the sprockets. The consequences if this happens are severe, as the chain is likely to get tangled up with the sprocket carrier and lock the back wheel. Alternately, if the chain tension was too tight this would create excessive stress on both engine, chassis and swingarm bearings.
2. Check your manual
The amount of slack varies from bike to bike so check your manual. The tension is usually measured midway between the front and rear sprockets at the bottom side of the chain. The up and down movement of the chain at this point should be measured and checked against the spec in the manual. This is usually quoted as a minimum and maximum in millimetres, for example 30mm-45mm.
3. Get ready to pull the pin
The spindle that goes through the wheel has to be loosened off and quite often there is a split pin that goes through a castellated nut. This acts as an added measure to prevent the spindle nut undoing. The split pin needs to be removed using a pair of pliers. With the pin removed you can then loosen the spindle nut.
4. Undo the adjuster lock nuts
Undo the lock nuts with a spanner on both the left and right- hand side. They only need to be loosened a couple of turns. With the lock nuts loose, the adjuster bolts can be turned. This arrangement allows the wheel to be moved backwards and forwards. When the wheel is shunted, back the chain tightens and vice versa.
5. Use the marks as guidance
There are reference marks on either side of the swingarm to help you align the wheel. The wheel has to move backwards in parallel, offering equal distance on both sides to maintain alignment. When you adjust the tension of the chain you should turn the bolts equally on either side, checking that the reference marks are the same either side.
6. Get the ruler out
As you turn the adjusters you can see the tension of the chain change. When you think it’s about right, measure it with a steel ruler or tape measure. If it’s OK, check the alignment marks are still correct and turn the wheel slowly to make sure the tension remains within spec. Tighten the locknuts whilst using a spanner to hold the adjuster steady.
7. Time to talk the torque
Use a torque wrench and single hexagon socket and tighten the nut to specification. The setting is usually quite high so make sure you don’t cause the bike to become unstable on the stand – 100Nm or more is quite common. When the nut is tight you need to recheck the chain tension because on some models it’s not unkown for the tension to change as the spindle is torqued up.
8. Give it some love
With the correct tension in the chain and the spindle nut torqued up correctly, make sure the castellated segments line up with the hole in the spindle. Refit the split pin or use a new one. When in place bend the ends over so it cannot come out. Apply chain lube carefully on the inside of the chain turning the wheel slowly so it gets an even coating all the way round. Check your work and you are good to go.
How to lube your motorbike chain
1. Lube it or lose it
Winter salt will destroy your chain in double-quick time so stay on top of cleaning and lubing. Alternatively you can fit an autolube system such as a Scottoiler to lube your motorcycle chain without using a stand. These devices automatically meter a precise amount of oil to the chain, and they work so well that they can substantially extend the life of your chain and sprockets.
2. Premium chain lube
Year-round riders should own two types of chain lube: dry lube for the summer months and a decent grease-based lube for the winter. The sticky grease-based lube holds up better against rain and dirt. Expect to pay around a tenner for the dry lube and £15 for the grease-based version.
Head here for the best motorcycle chain lube.
How to clean your motorcycle chain
This is a relatively simple process of applying degreaser and going at the chain with a cloth or a brush to remove any residue. Do the same to the sprocket for total peace of mind.
The right tools to work on your motorbike chain
In order to perform basic motorcycle chain maintenance, you'll need:
- Socket set (including sockets big enough to undo front and rear sprockets)
- Tool for breaking and refitting chain's rivet link
- Tab washer replacement for front sprocket nut
- Allen keys and screwdrivers as required (check manual)
- Torque wrench
- Rubber mallet
- Your bike's manual
- Centrestand or rear paddock stand
How to fit a Scottoiler, or automatic chain oiler
An automatic oiler can take a lot of the work out of looking after your chain and can actually extend its life. It’s especially useful in the winter months when salt, dirt and water from the road do their best to dissolve your chain before your very eyes.
Follow Stick’s tips below, and then sit back and enjoy the ride while this nifty kit busts the rust.
1. So long lube
An automatic chain oiling system is a real benefit for year-round and long-distance riders. By constantly supplying a precise amount of oil to your drive chain, it does away with the need for maintenance and keeps the chain in peak condition as you ride. Before you start, familiarise yourself with the instructions and the kit’s components.
2. Lay out and check
Once you have started to gain an understanding of how the system works, lay all of the parts out so you’re familiar with them and cross reference against the instructions to ensure you have everything you need. With this Scottoiler X System (£199.99) there are three main parts: a delivery tube, mounting bracket, and the reservoir/main unit.
3. Unearth the battery
As the Scottoiler is powered directly from the bike’s battery, you will need to gain access to the terminals and also find somewhere to mount the reservoir/control unit. Finding the battery is easy on this Suzuki SV650 as it’s in the traditional position under the rider’s seat. On many modern bikes the battery could be under a fairing panel so check your manual.
4. Location, location, location
The main unit needs to be located so the delivery tube is pointing downwards, allowing gravity to flow oil down to the chain. As well as the position of the delivery tube, you need to consider how easily you can get to the filler at the top of the unit, and also whether you can operate the buttons and see the LED status lights.
5. Tie and check
Once you find a suitable location, you need to cable tie the mounting bracket in place then double check that you have met all of the criteria detailed in the previous step. If the unit is mounted in a place where it is covered by a panel make sure the panel won’t snag the wires or tubing.
Stick's tip: Invest in a cable tie gun (from around £7) to tension and cut the ties
6. Route the power
Route the power cable to the battery. Aim to get it tucked away alongside an existing part of the bike’s loom. Secure it using cable ties, gathering up any excess lengths of wire into bundles and stashing them away. Don’t connect to the battery terminals at this point.
7. Free to flow
The oil from the main unit runs along a delivery tube to the tip of the nozzle and needs to be carefully routed with no kinks or sharp turns.
Our unit is mounted in a position just under the pillion seat, so the tube is neatly fitted in parallel with the subframe, before a gentle bend runs it back to the underside of the swingarm.
8. Clean and stick
The tube is secured under the swingarm using heavy-duty sticky pads. You’ll need to make sure the whole area is completely free of grease and grime. You’ll normally find wipes in the pack but for excessively grubby swingarms use some brake cleaner with clean paper towel. Stick the pads and clip the delivery tube into place.
9. Position your nozzle properly
Position and mount the dispensing nozzle and bracket. Like the delivery tube this can be secured using 3M sticky pads so make sure the surface is really clean.
Stick's tip: Spin the rear wheel back and forth to ensure the injectors don't catch
Adjust the final position of the nozzle to roughly the right place; this dual injector applies oil to either side of the rear sprocket. Cut the delivery tube to the correct length and fix it to the dispensing nozzle.
10. Prime and ride
Connect the wires to the battery then fill up the main unit with the oil provided. Prime the system and watch the oil flow down the delivery tube until it makes its way to the nozzle. When it has reached here you can stop the priming function. Top up the reservoir and re-install panels and seat. Test ride the bike and adjust the flow rate as necessary.
The right tools for fitting a Scottoiler
Allen T-bars 4-6 mm
Allen T-bars combine speed and feel, making them ideal for undoing and tightening non-critical bolts or nipping up fastenings prior to setting the final torque value. Pay £20 for a good one.
If you’re removing panels or fastenings with a screwdriver and your bike’s Japanese, invest in a JIS (Japanese Industry Standard) screwdriver (for around tenner) to get the best fit for your far-eastern bike’s bolts.
Leaving a long, untrimmed tail on your cable tie not only looks unsightly but can also cause damage to the surrounding loom or paintwork. Snip it off with some sharp cutters, which cost around £15, for a properly professional looking result.
Spanners are used when there’s no room to fit a socket. Combination spanners, open-ended one end and a ring spanner (like a flat socket) the other, are the best bet for reaching tricky nuts.
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