Much like the guy washing dishes non-stop at your favorite steakhouse, the chain of your motorcycle is likely one of the hardest working and most underrated components of your motorcycle. Working away tirelessly in the background entirely unnoticed. Unless you get a bootlace caught in it, or it starts giving off an unwelcome noise, you likely won’t give it much attention. The chain just gets left alone with a couple of sprockets jamming their teeth into it, getting a face full of consistent debris picked up from the road, such is life as a chain.
So, what’s the right chain for you, what are the differences, and why the hell don’t we all just have a shaft drive? Well, let’s take a look into the wonderful rolling world of this hardworking piece of alloy metal and see if we can’t find something that will yank your chain. X-ring, O-ring, or No-ring, what you should know about your motorcycle chain.
Photo: Leonardo da Vinci Sketch
An exciting history!
Ok, maybe the history of the chain isn’t as exciting as say the history of Grand-Prix motorcycle racing, but without that chain, the sport might be a little more like racing snails. An astute businessman named Hans Renold set out to work on the production of chains in 1879, and just one year later, he had invented the Bush Roller Chain. To date, this original design is the basis for every roller chain on the market. Renold's success garnered him a great deal of credit, though he might not have earned it all. If you flip back through the Leonardo da Vinci sketchbook on the shelf in your garage, you’ll see Leo thought of it first. Around the 16th Century, it was noted that da Vinci has sketched up a chain-like design with a roller bearing, proving to be well ahead of Renold's design by a couple of centuries. Not to worry though, I’m sure by now their legal teams have sorted out the details. Now let’s move on to who’s bikes are using what sort of chain and why.
Source: Wikipedia. Layout of a roller chain: 1. Outer plate, 2. Inner plate, 3. Pin, 4. Bushing, 5. Roller.
So, what’s the difference?
When you plan to run amuck across the countryside on your motorcycle, you are going to need to make a decision on what chain you want to have, know what it does, and why you want it. For the most part, your construction options are going to be comprised of alloy steel. The very exterior of the chain will have an outer plate, an inner plate, and a pin that goes through a bushing that holds everything together. Then to cover up the pin and the bushing there is a roller. This particular design is important because that little roller, when appropriately lubed, allows the chain to roll across the sprockets with less friction. When tensions are correct across the sprockets, and everything is well lubed, you can expect up to 98% efficiency from the transmission. This will be the standard layout of your basic roller chain. Smooth, efficient, and pretty straight forward.
The O-ring design is exactly the same design as above with one significant difference, the addition of the O-rings. The O-ring is placed between the inner and outer plates and serves a few purposes in its overall operation. First off, when it's being built, they insert grease via a vacuum into the area where the pin is before it's finally all riveted into place. This is then sealed off by placing the O-ring between the two plates. Keeping the grease inside to provide constant lubrication, seal the moisture and dirt out of that area to increase the lifespan of your chain. The major drawback is that once pressure is put on the rings, it dramatically increases the friction between the plates, taking away power from your overall drive. This is where the concerns over power come in for track racers, more on that shortly.
The X-ring design is similar to the O-ring design in almost every way, except, to increase the efficiency of the chain, the design was altered to an “X” style ring where the contact point of the ring would only be on four points. Unlike the “O” shape that touches all sides of the “O,” the “X” shape only touches where the four points of the “X” design touch. This design, therefore, gives less friction with the same benefits of keeping grease in and dirt out. They created a solution to a problem they invented. Clever or just clever marketing? I’m not so sure whose to thank here.
Honda CG125 With An Enclosed Chain
Who’s running what chains?
Many an off-road racer will tell you that using an O-ring chain will add too much extra drag and quite literally drag them down. It’s true that an O-ring or X-ring chain will indeed add some more drag to the equation. However, would there be enough drag to notice and affect a race time significantly, well that’s more likely in the head of the driver. Much like your favorite Brand-X oil VS a premium Castrol, the Castrol is likely better for your engine. However, if you sit on the seat of two different Triumphs with two different oil changes, I’m not convinced you’d notice the immediate difference. I’m sure it can lead to a slippery debate though. That being said, you are likely going to see the concerned off-road racer utilizing the non-O-ring chain. This chain is also considerably cheaper than the X or O types. The price tag included with that decision for some people often outweighs all the research in the world.
X’s and O’s overall are going to make up a greater spectrum of the purchasing power. For anyone whose main decision isn’t fully leveraged by the price point, they are likely to use an O or X-ring chain. The price difference between these two options are not so bank-drainingly different to have you run one chain over the other. If you are looking to argue that an X-ring has considerably less friction than the O-ring based on its design, then it’s basically the same idea as choosing to fill your gas tank with mid-grade gasoline as opposed to premium-grade. You make this choice because you want to feel like you care about your bike but aren’t sure you can justify the top of the line price point.
What are my other options?
Unless you have your hands on a smaller overseas bike like the Honda CG 125 with an enclosed chain that protects it from dirt and keeps the lube on the inside. Or another lesser known model like the rare Norton Classic or Norton Navigator motorcycles with the same enclosed design. Your options are going to be the X, O, no-ring chains, a belt, or a shaft driven motorcycle. Wait, what, you can get the belt or the shaft too? Well, if you want to diversify your options a bit more, here’s what other options you could potentially run back there.
Not nearly as many, yet still available, are the belt driven motorcycles such as the BMW F800GT, the Buell Blast, and the Suzuki Boulevard S40 just to name a few. The belt on these motorcycles are typically made from an aramid core structure that is wrapped up by a synthetic rubber exterior. The teeth are produced from a high-modulus compound that are designed to fit perfectly into the teeth of the rear drive sprocket. The benefit here is that they are low-maintenance, have a considerably longer life, require no lubrication, cannot rust, don’t stretch/suffer from elongation, and are much quieter than a regular chain. The downside is that if you ever needed to change one these belts, it can prove to be a bit challenging. Altering the sprocket size for power or speed is much more difficult as well and on a cost per unit basis, they generally costlier.
Your next option is more similar to a car's design. It utilizes a shaft drive and thus changes the design completely from the chain or belt options described above. A shaft drive takes the power of the engine and shifts it to the shaft. That shaft then meets a set of bevel gears that are at a 90-degree angle with one another, where the power is then transferred to the rear wheel. Voila, you're moving! BMW is one of the primary users of the shaft drive system and has over the years tried to improve its overall efficiency. However, it still gets 2nd place in popularity to the chain drive system. A shaft drive is excellent in that it is the quietest of all the drive options and requires next to zero maintenance over the life of the motorcycle. The setbacks to this design are that they cost much more to build than the simple sprocket and chain set-up, and are considerably heavier. To add to this, when you are considering a power output to bike ratio, the shaft drive loses a lot of power with its bevel design and the added weight. A deal breaker for some and to others, it has no barring in their decision.
Image: 1988 Norton Enclosed Chain. Classic-British-Motorcycles.com
What to consider on your next purchase...
If it’s time to pull the trigger on a new chain or maybe even a whole new bike here’s what you might want to consider to make that decision:
Cost: If you rarely ride the bike and perhaps only clock in a few miles here and there throughout the year, then get the cheapest standard chain you can buy. If you are selling the bike and it will require a new chain to seal the deal, again, go for the 'Plain Jane' basic chain. If you are just a cheap bastard, then, well, cost is King!
Longevity: When you finally pull the trigger on that round the world adventure or even a coast to coast two-weeks of terror trip, you’ll want to get your hands on an O-ring. Or even better, the X-ring chain that will last longer and keep your precious bike grit and grime free.
Riding style: A dirt track racer who feels that mere seconds shaved off his riding time might have him placing in a podium-worthy position, will probably have excessive motorcycle maintenance already in his daily routines. If you are this kind of rider, you should go with a standard roller chain. You’ll need to clean and lube these consistently. You’re probably cleaning and lubing the bike after each race already, so what’s one more job to add to the list.
Who cares: So, you're over it and don’t want to get on your knees with a toothbrush and some chain wax every weekend. Well then, it might be time to pony up for that BMW K1600GT that you’ve been considering spending your kids' college money on. No fuss, no mess, no problem, it's as easy as calling up your local dealer and telling him to give you the shaft!
Header photo: @bigbearboyes