Aug 12, The Chain and Sprockets on a Dirt Bike need this to be Efficient

Giving attention to your chain and sprockets by ensuring the proper chain adjustment, as well as maintaining proper chain alignment can have quite a bit of beneficial qualities such as increased power, avoiding broken engine cases and DNF's, or any other number of other calamities you may be able to avoid if your chain were to suddenly derail.

It's really no secret that if you're on the power heading towards a massive motocross or freestyle motocross gap and you end up having problems with your chain and sprockets, such as derailment or breakage of a chain it can be disastrous, as well as imagining what you're going to be up against should you have problems miles from the truck while pounding out laps on a woods loop, or just trail riding with your family and friends.

Having problems with your chain and sprockets or any related components could possibly leave you pushing a 200+lb dirt bike out of the woods and is no fun, as the excitement only gets better if you should happen to be fortunate enough to be faced with pushing a dirt bike through a section of sand or uphill, so paying attention to your chain and sprockets and keeping them in check is a pretty good idea.

Right here you've found the source you need to save yourself money from having to replace expensive engine cases, or worry about getting your chain all snarled up, potentially locking up the rear wheel and causing a violent swap, so this article outta hook you up with the rundown on what you need to know related to laying the power down, along with some recommendations on component replacement as there are many different components besides the chain and sprockets that are at work in this operation.

Beginning at the front sprocket which you may have heard referred to as the "Countershaft Sprocket" and moving towards the rear wheel you have a chain, a chain slider on the swingarm, chain rollers above and below the swingarm pivot area, a rear chain slider / guide and the rear sprocket, all of which are going to be discussed.

After each ride or race you should always wash the dirt bike then check over several different things as are listed on the the dirt bike maintenance page and the condition of your chain and sprockets is an important one to keep tabs on, so this is the hook you up on what you need to know.

First, you may like to know (if you haven't yet figured it out) that a well lubricated and adjusted set of chain and sprockets is incredibly simple and is also an extremely efficient way of transferring power to the rear wheel, but a chain that is not aligned properly, or a chain that is dry and lacking lubrication, as well as chain and sprockets that are caked with mud or other debris, such as having vines wrapped in them can create a noticeable amount of friction and drag in the drive line, resulting in a noticeable decrease in power, so much so that you may feel a loss of power in the seat of your pants, so be sure to keep your chain and sprockets lubricated, as well as clean of buildup for the most efficient power output, as this will greater enable you to pull the competition on the straights and other parts on the motorcycle may even last a little longer.

Additionally, It is also important to remember the forces that are placed on the chain when riding, such as when powering away from a corner, landing from a jump or when launching across a creek bed or other irregularities on the ground, as well as the force being transferred through the chain when powering up a vert wall and launching off the top.

Before you get too far ahead of yourself you may want to be sure your chain and sprockets aren't clapped out to begin with.
A few good indicators of whether your chain and sprockets or other related components are worn out are: Missing teeth from the sprockets.Sprocket teeth curled over in the shape of a wave.Sprockets that are worn so badly that the chain is slipping on the sprockets.Chain rollers that nothing is left of, or the bearings are seized so the roller does not rotate freely.Chain rub blocks that are worn through where as the chain is gnawing into the swingarm or rear chain guide outer shell. (If the factory guide is used)Rear chain guides that are bent.Bent or otherwise damaged sprockets. (rear sprockets can be commonly damaged by being struck by another rider in racing environments)Additionally, it's a good idea to check the chain for kinks by slowly turning the rear wheel while watching the chain and listening for any binding links as the chain travels around the sprockets and also check the chain's side to side play by moving the chain from side to side by hand insuring that the chain does not deflect a great deal, A chain that is not worn badly and is in proper adjustment, generally should not move further than the width of the front chain slider.

If you notice any parts of the drive train that appear to be in bad shape be sure to replace these components immediately after cleaning the dirt bike and drying of all critical areas.

Note: When replacing the chain or either front or rear sprocket, be sure to only replace all 3 pieces as a set, otherwise wear of any new parts will be greatly accelerated. That is, replace the chain and both sprockets as a set, and do not only replace the rear sprocket while using an old chain and countershaft sprocket or any other combination of mismatched parts.

There are several good choices of chain and sprocket combos available so be sure to review the choices available for your bike and pick a chain and sprocket combination that you feel is best for your intended use.

If you are in need of a front chain slider there are aftermarket choices available in many different colors such as the TM Designs chain slider that actually last longer and will perform better than the OEM units.

If the chain roller(s) are worn out, TM Designs have chain rollers available as well, and some are designed with what is known as a "PowerLip" which is designed to help reduce chain drag, so these are an excellent choice to keep in mind when replacing either your upper or lower chain roller.

If a rear chain guide is what you're after, there are aftermarket rear chain guides available that are also manufactured by TM Designs and these replace the factory chain slide block and outer shell as a complete unit and are nearly indestructible, as they can be distorted when crossing fallen trees or anything of the like that may strike the rear chain guide (since it is a low hanging piece) and return to their original shape, whereas the factory chain guide, if bent, will remain bent and greatly accelerate the wear of the chain and sprockets, or even possibly cause chain derailment, for this reason the TM Designs rear chain guide is an excellent choice for replacement of the rear chain guide, especially if riding off-road type of disciplines is on your agenda.

If the chain and sprockets as well as all the other related components look good (or once you have some new chain and sprockets, a chain slider, chain guide or roller(s) on the way) it's time to make sure the dirt bike is clean and ready to be serviced so you can adjust the chain properly and start planning your next trip to attack the track, trails or ramps.

Note: If you're replacing your chain and sprockets, you may want to review the "Final Drive Ratio" chart below, as this will provide the gear ratios of common sprocket combinations.
If your front (countershaft) sprocket is secured with a bolt, bolts or a nut, It's important that you loosen any threaded retaining device with the chain installed, so as to be able to prevent the sprocket from turning, since the chain and sprockets will still be a complete set the whole operation can be held from turning by application of the rear brake.

When removing any retaining bolt(s) or nut from a countershaft sprocket, it is okay to use an impact wrench to remove the securing bolt(s) or nut, but after the chain and sprockets have been installed as a set, be sure to use a quality torque wrench during reassembly to tighten the bolt(s) or nut securing the countershaft sprocket and this can be accomplished by holding the rear brake to prevent the sprocket from turning during torquing.

If your dirt bike has a washer with a tab that is bent over and securing the nut on the countershaft sprocket from coming loose, be sure to replace this lock washer upon removal, as these are designed to be used only once. If the sprocket is retained with a snap ring or circlip, it is a good idea to also replace the snap ring / circlip after removal, but the snap ring / circlip can be reused if necessary as long as it is removed and reinstalled carefully so as to not expand it so far during removal or installation that it loses it's spring tension.

If the countershaft sprocket is held in place with a snap ring / circlip, it's a good idea to apply some "yamabond" or another similar type of sealant to the snap ring once installed and securely in the groove, as doing so will provide added assurance against the snap ring from coming off the end of the shaft.

The front chain slider is a common wear item that is designed to keep the chain from sawing through the swingarm. So... If your chain slider is worn, then replacement is important so as to keep your swingarm intact and not losing weight from the chain sawing through it.

There are aftermarket chain sliders available which are more durable than the OEM unit and also come in different colors, so these are an option to consider if replacing the front chain slider.

Additionally, you may find that replacement of the swingarm chain slider may be possible without removing the swingarm by contorting the slider in ways it wasn't designed, but if the front chain slider is in need of replacement, this is a good time to remove the swingarm, as well as the shock linkage (if applicable) from the dirt bike and service the swingarm and linkage bearings in these components, finishing the job by fitting the chain slider to the swingarm, then reinstalling the swingarm (and linkage if applicable and removed) to the dirt bike, and reassembling everything that may be removed, as well as making sure the chain is adjusted properly and the chain and sprockets are in proper alignment as will be covered below.

Keeping the motorcycle's chain roller(s) fresh and rolling smoothly will help keep everything working smoothly, so pay attention to the chain rollers when prepping the bike for a ride or a race and if the rollers are worn or the bearings inside of the roller (if equipped) are feeling rough, or if there is play in these bearings, then the chain roller(s) should be replaced.

So you're aware... The bottom roller does take quite a bit of punishment from the chain so pay close attention to it, as well as the top roller, as the top roller is designed to limit the chain's movement when landing from jumps, or any other condition that causes the rear wheel to blow through the travel.

Long story short regarding chain rollers is... The upper chain roller keeps the chain inline during hard landings or bottoming of the suspension, as well as keeping the chain from gnawing through the air intake boot or subframe during travel of the rear wheel, so both of the upper and lower chain rollers are important to keep an eye on and TM Designs manufactures a very durable chain roller that you may want to consider.

Moving towards the rear you're going to find a chain guide / slider and this is usually held to the swingarm by through bolts and in OEM applications the rear chain guide is normally made of an outer shell with an inner insert that is designed to withstand the chain being in constant contact, as well as keeping the chain feeding onto the rear sprocket preventing derailment.

Most original rear chain guides are 2 piece and the outer shell that holds the slide block is usually aluminum, or it may have been upgraded to carbon fiber for the "Bling" effect, but the problem with these is that aluminum bends and stays bent if struck, and carbon fiber breaks, both of which scenarios can cause instant problems with the efficiency of your chain and sprockets so fortunately, TM Designs has developed a rear chain guide that is nearly indestructible and if you are going to be replacing the wear insert inside the OEM chain guide shell, it is highly recommended that you upgrade to a TM Designs chain guide.

The rear sprocket is where the power meets the wheel and is usually also the first component of the drive train to show noticeable wear and this is especially true with an aluminum rear sprocket.

Luckily, the people at Renthal have taken notice of this and have developed a "Twin-Ring" sprocket that is designed to address this issue as this hybrid sprocket has an aluminum center to save weight with an outer steel ring that provides greater wear characteristics, so this is an excellent choice when replacing the chain and sprockets as a set and the "Twin-Ring" sprocket can usually be added to any chain and sprockets "kit" while selecting preferences such as gear ratios, colors and the like.

When replacing the rear sprocket, be sure to use the proper size allen tool to loosen the bolts if threaded into the rear hub, and if the dirt bike has a bolt and nut configuration, be sure to loosen the nut from the back of the sprocket while holding the allen bolt from turning with the proper size allen wrench from the front, otherwise damage to the bolt may occur.

If the bolts, or nuts and bolts that secure the rear sprocket are in rather bad shape then you may want to pick up a sprocket bolt kit so as to enable a clean installation of the rear sprocket.

While the rear wheel is removed from the dirt bike for replacement of the rear sprocket, it is advisable to check the condition of the rear wheel bearings by turning them with your finger. If the wheel bearings feel notchy or rough, then now is a good time to replace these.

When reinstalling the rear sprocket to the hub be sure the area where the sprocket attaches to the hub is clean and free of any burs or other imperfections then tighten all the bolts evenly and in a criss-cross manner, and on the type with threaded holes in the hub with no nut at the rear of the sprocket make sure you clean the bolt holes in the hub and the bolts with a cleaner such as "brake clean" then apply blue loctite to the threads of the bolts before installation and tightening.

Once you're done with the rear wheel and the sprocket is installed and the wheel bearings feel alright or you have replaced them, before you reinstall the rear wheel, you should remove the chain adjuster bolts from the swingarm (if equipped) and coat these with an "Antiseize" compound so as to prevent the bolts from seizing in the aluminum, making future chain adjustments very difficult if not impossible and requiring inserts to be placed into the swingarm to correct the situation.

When replacing your chain and sprockets, when you pull the chain out of the packaging, you will likely find out that the new chain is much longer than the chain that you just removed but before you do anything keep reading.

Once everything is back together, It's a good idea to put some thought into where you want the rear wheel to be positioned in the swingarm and then position the wheel there as a starting point. Remember, The rear wheel position can affect handling characteristics in a noticeable way, such as increasing straight line high speed stability and decreasing the likeliness of wheeling by moving the rear wheel towards the rear of the adjustment range, or a bike can be made to turn sharper and be more responsive to throttle input by shortening the wheel base (moving the rear wheel forward) so rear wheel position is something that some thought should be given to before wrapping the chain around the sprockets and determining the length.

Once the wheel position is determined, wrap the chain around the sprockets (with the wheel set in position and the axle nut snug). Over lapping the ends of the chain you should be able to determine where you need to break the chain.

Once you know where to break the chain, grind the peening off the end of the pin(s) that are to be removed, and use a quality chain breaker to break the chain, or simply grind the end of the pins off where you want to break the chain and drive the link out using a hammer and punch supporting the chain over a vise with the vise jaws "open" just enough to allow the link being removed to fall out.

Once the chain and sprockets are installed and the chain is wrapped around the sprockets, be sure to position the master link so the clip is towards the outside of the chain (facing you) while also insuring the orings (whether oring or xring style) are in place properly during assembly of the masterlink to the chain.

Once you are this far, install the master link clip so that the closed end faces the direction of travel, then lubricate and adjust the chain as discussed above.

Lastly, On the topic of chains and master links, if you have a cheap pair of pliers laying around, you can grind about 1/16th of an inch off the end of one side of the pliers and leave these in your tool box that goes to the track with you for making removal and installation of the chain's master link easier.

When cleaning the dirt bike and addressing the chain and sprockets in the future, (provided things aren't worn out as discussed above) it is ideal to spray the chain with the cleaner of your choice from a hand held pump sprayer (Simple Green works well) while turning the rear wheel, then once soaked with a cleaner, using a common household type of stiff bristle nylon brush (This generally works better than any of the gimmicky chain cleaning brushes), scrub the chain including the side plates, and the top and bottom of the links as well as trying to get to the teeth on the sprockets while you're at it. (cleaning of the sprockets may be easier with "scotch-brite").

Once the drive train is soaked well with cleaner and has been scrubbed, it is important to rinse everything well and if you have a non-oring chain, it is alright to use a power washer, but on a sealed chain such as an oring chain or any other variation of a sealed chain such as an xring, you may want to keep a pressure washer away and just use a moderate pressure, such as from a garden hose to rinse the chain so as to not disturb or dislodge any of the seals within the chain, or to force grit particles deep within the chain rollers where they will not be able to escape and will cause accelerated wear of the drive chain.

Once the drive train is clean, and you have also finished with the cleaning of the rest of the dirt bike and you've shut the water off, you need to use compressed air to dry the chain and sprockets as well as other related and non-related components on the dirt bike as shown in the article on washing a dirt bike.

Once you have begun to dry and displace the water from components as mentioned in the article on washing a dirt bike, it's time to focus on the chain.

Using compressed air with a blow nozzle, slowly turn the rear wheel by hand while at the same time using the compressed air to dry the chain and displace water from between the side plates and rollers as well as from the sprockets and general areas.

Once the motorcycle is clean and dry it is important to lubricate the chain with a quality chain specific lubricant then once lubricated check into the adjustment and alignment of the drive train as is discussed next.

Well, way down here is the rundown on making sure you have the proper amount of slack in the chain, so as to permit unrestricted travel of the rear wheel over irregular terrain or when landing from a jump.

Having your chain free-play set properly, as well as having the chain and sprockets aligned properly will enable you to extract the maximum amount of performance from your bike, as well as avoiding any derailment problems and accelerated wear of components.

Once everything is clean, grab a small ruler (A 6" machinist steel rule works well) and find a point on the chain to reference from that is slightly behind where the front chain slider ends.

A good point on the chain for this is usually one of the pins in the chain as these are centered within the chain and are an excellent reference point.

At this point you will want to take a measurement with the chain at rest on the slider while the dirt bike is on a stand with the rear wheel off the ground but just hanging naturally. Forget all the stuff you've heard about taking a measurement when the swingarm is parallel to the ground or at full travel, taking a measurement with the swingarm at these points is usually very difficult and a hassle.

By the way... How were you planning on getting the swingarm perfectly parallel to the ground or at full travel without removing the shock(s) and keeping it in this position long enough to take an accurate measurement?

Forget the straps or the big dude that was going to reach across the seat and pull the swingarm up or sit on the bike compressing the suspension. Here's a better and easier way.

Check this out. Once you have a spot on the ruler visualized with the rear wheel at rest and the rear shock fully extended, hold the ruler still while lifting the chain with your other hand until taut, then take another measurement. The ideal free-play setting for a chain is about 1.4 - 1.5 inches from the first measurement while everything is at rest as discussed above. If the free-play is adjusted to where there is 1.4 - 1.5 inches of slack in the chain, you will have plenty of free-play to allow the swingarm full travel without pulling the chain so tight that things are in a bind resulting in possible breakage of the chain, which usually results in broken engine cases and is very expensive to repair, as well as avoiding prematurely worn swingarm and engine bearings due to the load placed on these components from a chain that is too tight, as well as keeping the chain from slapping against the swingarm.

If your chain needs adjusting such as when installing a new chain and sprockets combo or when compensating for wear of drive train components the following tips will ensure a trouble free adjustment.

When adjusting the chain (taking out slack) a tip that works well is to loosen the rear axle nut but still leave a moderate amount of pressure on the axle nut so the rear wheel cannot be slid in the adjusters by hand, then use the adjusting bolts (or other means of adjustment as provided by the manufacturer of your bike) to push the wheel back evenly on each side making sure the alignment marks remain equal on either side before tightening of the axle nut further, and to the factory recommended torque value as can be found in a factory service manual specific to your bike.

Once the axle nut is tightened to the factory recommended torque value, apply light pressure against the axle blocks by holding the chain adjuster bolt (if equipped) with one wrench, then firmly tighten the chain adjuster lock nut with another wrench simultaneously.

The ideal free-play of the chain is fairly easy to achieve but maintaining proper alignment is equally important and the marks on the factory adjuster are not always the best or accurate due to tolerances in the manufacturing of the frame and swingarm, so you may want to consider some aftermarket axle blocks in the color of your choice to aid in alignment of the rear axle and add a little bling to the rear of your swingarm, as well as picking up a chain alignment gauge to ensure proper alignment of the chain.

Now that you've gave your monster some fresh teeth,
Why not take it out for a Flogging??
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