How To Replace Your Motorcycle Chain and Sprockets | The Shop Manual

If your motorcycle's drivetrain has kinked links and curved teeth, then it's time for a new chain and sprockets. This is a job you can easily DIY, and I'll show you how. Let's open up the Shop Manual. This episode of the Shop Manual is powered by Duraboost batteries. Get 10% off your Duraboost purchase at RevZilla.com with discount code 10OFFTSM. We've got videos explaining how to tell if your chain and sprockets are worn out, as well as how to navigate selecting new parts. Now, we'll show you how to actually remove and replace everything. And for that, you're going to need a rear stand, a chain tool to break and rivet the chain, tools to remove the rear wheel, tools to remove the front and rear sprockets, and calipers for confirming link width and rivet flare. First step is to get the back of the bike up on a rear stand so that we can break the chain. Breaking the chain entails driving out a link pin, and I prefer to do it at the rear sprocket, since the sprocket keeps the chain stable as I work. You might have heard people recommend grinding a pin head off, and you can certainly do that either with an automotive grinder or even a Dremel tool, and that's going to make driving that pin out easier, and it might even be necessary if you're working with a light-duty tool. However, PBR tool from Motion Pro here is built like a tank, so no prep necessary, I can drive a pin straight out. Lift the chain off the sprocket, but don't pull it off the bike yet, because we're going to use it to help us get the front sprocket off. Different manufacturers use different approaches to secure the front sprocket, and unfortunately, the most common is also the most challenging. It's a huge nut that's torqued to a million pound-feet, and when you try and loosen that thing, the engine is going to want to turn. Pressing the rear brake or jamming something between the swing arm and tire while the chain is still on are common approaches for keeping the sprocket from rotating, but none of them are as simple and foolproof as looping the chain around the axle. So remove the wheel, slide the axle back into place, loop the chain over it, and then secure the chain with a six millimeter bolt and nut. If there's a retaining plate on the front nut, use a chisel and hammer to flatten it, and then break out your impact gun, breaker bar, or a ratchet with a pipe extension, and give that nut hell. If it's really stubborn, be like Archimedes and get a longer lever. Once that nut breaks free, you can breathe a sigh of relief because the hardest part of the job is over. Go ahead and pull off the chain, spin the nut all the way off, and then remove the old sprocket. And if you're so inclined, now is a great time to scrape all the crud off the side of the engine and the inside of the sprocket cover. Now slide on your new front sprocket, bend the lock washer, add some Loctite to the threads if it's called for, and then spin on the nut. Now route the chain so it will keep the sprocket from rotating clockwise, and torque the nut down to whatever ungodly number is listed in your owner's manual. In this case, it's 110 pound-feet. Once that's done, bend the lock washer up against one of the flats on the nut. Compared to the front sprocket, swapping the rear sprocket is a breeze. Remove the nuts, replace the sprocket, then tighten the nuts in a crisscross pattern in stages up to the torque listed in your owner's manual, which is typically between 40 and 50 foot-pounds. Now we are ready to install the new chain. Loop the chain onto the bike so that the ends meet toward the back of the rear sprocket. Prep the master link by slathering the pins and o-rings with the included grease pack. I'll also put some grease inside the link bushings. Now put an o-ring over each pin, slide the link in from the back, then pop two more o-rings over the ends and put the side plate on. The side plate is an interference fit, so you're going to need to use your chain tool to press it on. And here's where the process starts to get precise, so you need to slow down and check things. You want to press the side plate on so that the link matches the width of the other links. So give the tool a quarter or a half turn at a time, then remove it and take measurements with your caliper. If you push the side plate on too far and squeeze the o-rings out, there's really no way to recover from that. So again, go slowly. With that done, we now need to deform the ends of the link pins, so this is a permanent installation. Now it's going to take a lot of force, so make sure you've got grease on the threads of your chain tool. And I'll also point out that this link is somewhat unique. Typically what you'd see is hollow pins. These are not hollow. This is what's called a quad stake. The good news is the Motion Pro tool does come with a quad stake tip, but as you can see, I've never used it. I've had this tool for 15 years. These are pretty rare master links, but the idea is the same. You're deforming it a set amount, typically 0.25 to 0.55 millimeters. So if we measure the existing pin before it's been deformed, we're at 5.25. So we're going to aim for between 5.5 and 5.6 millimeters. And similar to the side plate, you want to go a little bit at a time, a quarter to maybe a half of a turn, then pull the tool off and measure the link. The second pin is the same procedure as the first. And once you set the chain slack, confirm wheel alignment, and torque through your axle, you're good to go. Keep your new chain and sprockets clean and lubricated, and depending on your bike's power output and your riding conditions, you should be able to cover 15 or 20,000 miles or more before you have to deal with all of that again. Shop manual friends, thanks for spending these precious minutes with me learning about how to change your motorcycle chain and sprockets. Now, in order to get to that step, you have already had to select your chain and sprockets, which can be a little daunting. Thankfully, if you scan that QR code on your screen, you will see an article and video I did that will streamline the process of selecting new parts for your bike. Speaking of which, if you buy those parts, or a helmet for yourself, or a jacket or tires for your bike from RevZilla, you will be supporting not only the shop manual, but Zach's daily rider, as well as CTXP. So, please support the shows you enjoy watching. Thanks.