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EVERYTHING YOU NEED TO KNOW ABOUT CHAINS

Display photo of a dirt bike chain

Educate Yourself on Motorcycle Chains

You’ve finally found it. The readable, organized, and informative post that’ll give you everything you need to know about chains. No, not the ones you wear around your neck (unless you’re THAT into riding), motorcycle chains! Read on to find out all the different components that make up a chain, the parts that go with it, and how to choose and take care of everything—the right way!

CHAIN COMPONENTS

There’s more than meets the eye when it comes to motorcycle chains. Let’s break it down to each individual piece; what they’re called and what they do.

Diagram of the inner workings of a motorcycle chain
  • Bushing: a thin tube/sleeve that allows relative motion by sliding, as compared to rolling. Bushings are usually used in bike chains to separate the rollers from the pins.
  • Rollers: A cylinder that rotates around a central axis. The center area of the chain, the rollers are the contact points for the sprocket
  • Pins: The axis of the rollers, these are what hold the side plates of the chain together.
  • Side Plates: the actual linking portions of the chain. There are inner plates, and outer plates, both with a distinct design for each one.
  • Masterlink: The most important chain link; this is the side plate that allows you to disconnect and reconnect your chain. There are 3 types of these:
    • Slip-Fit: the most commonly used, has a clip that secures onto an adjacent side plate
    • Press-Fit: also utilizes a side clip, but requires the use of a chain press/breaker to install
    • Rivet: does not use a clip, instead uses hollow-ended pins that act like rivets. These are flared out with a tool to hold the side plate on the other end.
The physical difference between a standard chain and an o-ring chain.

There are two main types of chains: standard and O-ring. Standard chains are thinner and lighter, allowing a higher top speed. However, these tend to wear and tear much more quickly than an O-Ring. O-Ring chains are bulkier and heavier than the standard, but stay self-lubricated and fend better thanks to the added rings between the inner and outer plates. Basically, if you race: standard. If you’re more of an off-road/adventure rider, definitely go for an O-Ring.

CHAIN DIMENSIONS (How to read chain sizes, and pick the right one)

Illustration of what a pitch, roller diameter, and roller width look like.

Get ready to sound like an expert. Chain types are identified by their 3-digit number. The first digit represents the distance between pins, which is called Pitch. Almost all chains are measured in 1/8” increments. For example, if a chain’s number begins with 4, there’s 4/8” of a gap between that chain’s pins. 5 is 5/8”, 6 is 6/8”, and so on. That’s the ‘5’ in your standard 520 chain.

Product image of D.I.D's standard 520 chain.

But what about that 20, you ask? This represents the chain’s inner width. Going off the 1/8” measurement, the ‘2’ is really like a ‘2.0’, since it is 2/8 (or ¼) of an inch. And that’s how you get the ‘20’ in 520!

The thickness of the side plates is 1/8th of the pitch, except “extra-heavy” chains, which are 1/32” thicker, and designated with an ‘H’ (Ex. 630H).

If there is a secondary number, this is going to refer to the literal number of links that are in the chain.

There are two factors when it comes to figuring out what chain to select; the working load and the rpm of the smaller sprocket. The working load sets the lower limit for pitch, and the rpm/speed sets the upper limit. As a general rule, you should use as large a sprocket as possible. This is because the larger a sprocket is, the less working load for a given amount of transmittable power, therefore enabling the use of a smaller-pitch chain. The smaller the pitch, the less noise, wear, and power loss will be experienced. Just make sure your chain speed stays under 1,200 feet per minute!

CHAIN SYSTEM (DRIVETRAIN) PARTS

Okay, so we’re straying a tiny bit away from chains, but let’s quickly cover all the required parts that make a drivetrain actually work! First off is the chain slider. Sitting on top of the swingarm, the chain slider (a.k.a. rub plate) helps to ensure the chain is fed into the front, smaller sprocket properly. Not only that, the slider acts as a barrier to prevent the swingarm and the chain from grinding against each other.

A diagram showing various elements of a dirt bike drivetrain.

Right next to the slider is the chain roller. Now, there are actually 2 of these. One is located on the bike’s frame, a bit above the slider. This is so that when your suspension compresses, the chain doesn’t grind against the frame and cause damage. The other roller is located more towards the back. This guarantees to keep the tension just as it’s going towards the rear wheel, into the chain guide.

The chain guide, well, guides the chain directly onto your rear sprocket, making the wheel actually turn.

Hopefully, you know what a sprocket is, right? It’s the toothy/spikey wheel that the chain wraps around. The thickness of the sprocket should be approximately 85-90% of the span of the rollers of the chain. Remember, you pretty much always want to go for the largest sprocket possible.

CHAIN INSTALLATION/REPLACEMENT

A close-up of a new chain installation.

Every so often, you’ll need to replace your chain. It can happen anytime, so it’s always a good idea when riding to keep a spare and a chain breaker in your toolkit. Check out what other essentials you should keep in your toolbag here. If your chain is a slip-fit, then technically you won’t need one. Any other type though, having a chain breaker will make your life a heck of a lot easier.

The Motion Pro Chain Breaker, an essential tool for the regular rider.

Line up the breaker dead-on to the pin of the link you’re trying to remove, so nothing gets bent or broken. You might need to remove a few links to get the right amount of tension but always lean towards having more links than less. It’s way easier to take a link off than to add one on.

CHAIN CARE

Properly cleaning and lubricating your chain will drastically increase its lifespan and allow the rear wheel to spin much more freely. Avoid pressure washing and wire brushing, as this can actually force in contaminants and destroy seals. It’s best to manually scrub and rinse your chain, using soap and degreaser. Then put some lube on to help prevent it from rusting.

Chain lube being applied to a dirt bike chain.

Another tip to extend the life of your chain/drivetrain is to add a little lube to pivot points. Put some on both rollers, and add a bit to the topside of the chain so it disperses into the joints as it rotates.

Bam! You’re now (arguably) a total expert on chains right? Did you learn anything? Don’t forget to comment/share! You can get chains, all the rest of the drivetrain parts, and practically any motorcycle part you can think of at BTOSports.com!

Action shot of dirt getting kicked up by a revving dirt bike.
Trevor Edwards
A wordsmith that also keeps it wide open, I have been known to win a race or two. The world of music and dirt bikes come together in my life for an epic ride sesh!