Swapping out your bike’s worn out chain and sprockets may seem like a daunting task. But it’s not as tough as you may think. Here’s all it takes to do it yourself … and save a bunch of money in the process.
Loosen up! Sure, you can’t wait to get that bike up on the stand and prepped for the task. But when changing sprockets and chains, the first step is to break loose those snug front and rear sprocket fasteners. The best way to do that is to keep the bike firmly planted on the ground so the rear wheel and that front counter sprocket are less inclined to spin when you start cranking on that wrench. You may also find that a wrench with a nice long handle will give you the additional leverage you need to break stubborn nuts and bolts loose. No need to remove the fasteners completely at this point; just get ‘em loose.
Up, off, and away. Next step? Get the bike up, get the components off, and throw the old stuff away. With the front and rear sprocket fasteners loosened, now is the time to put the bike up on a stand with the rear wheel in the air. Loosen the rear axle nut and then loosen the chain adjusters to create enough slack for the chain’s master link to be easily removed or far enough to allow the entire chain to be pulled from the sprockets. Just be sure to loosen the adjusters evenly on each side to maintain alignment. Now you can remove those sprocket bolts you loosened earlier. Now pull the sprockets off the bike and throw them away, along with the old chain.
Get it on! Now we’re ready to install those fresh new sprockets. Slip those shiny new components into position, coat the bolt threads with a quality threadlocker and then torque them down according to your bike’s owner’s manual. On the rear sprocket, be sure to tighten fasteners gradually in a crisscross pattern to assure the sprocket is seated evenly.
Your old chain had likely stretched a bit over time and the new one will initially be shorter, so loosen those chain adjusters nearly all the way before trying to fit the new chain (again, do that evenly on each side). Wrap the new chain around the new sprockets and test fit it to make sure the length is good. The right length will allow you to establish the appropriate slack adjustment with the new chain, while still allowing sufficient range for chain adjustment as the new chain begins to “stretch” as it breaks in. If the chain is too long to start with, you can easily remove a link or two with a simple chain breaker tool.
Yes, Master. You will need to connect the two ends of the new chain together with a master link. A master link is, in essence, a regular chain link with one side removed so that its pins can slide through the holes of the two chain ends. Then, the seals (if used) and a plate are installed and fastened into place. There are two types of master link: a clip-style master link and a rivet-style master link. The clip style is simple to install and remove at any time. The U-shaped spring clip slips over the master link plate and is held into a groove on the master link pins. When installing a clip-style link, be sure to position the closed end toward the direction of forward rotation (the closed end leads, the open end trails). For a stronger, more secure option, a rivet-style master link can be installed. You’ll need a simple chain tool for the job, but it’s still very doable for the DIY mechanic. Just follow the directions that come with the tool. With either type of master link, if you’re installing an O-ring or X-ring chain, after slipping the master link into place, be sure to install the seals over the exposed pins before installing the link plate. Use the other chain links as reference.
Don’t be a slacker. You’re almost done with the job, so don’t bail now. Adjust your bike’s chain slack to proper specs (refer to our earlier blog, “Well Adjusted” for tips about proper chain adjustment) LINK: http://sunstar-braking.com/news/2019/02/19/good-bike-behavior-calls-chain-thats-well-adjusted/
Be sure to tighten up the axle nut and recheck the tension one more time. You’ll also want to give that new drivetrain a good start by lubricating it before you roll. For details about proper lubrication, you may want to read, “Feed Me!”
Ride on! That’s it. You did it. Now it’s time to hop on and give it a road (or trail) test. Enjoy the fresh performance of a new drivetrain and the satisfaction of knowing that you just did the upgrade yourself and saved yourself a bunch of money in the process.
When it comes to selecting the right components for your bike’s drivetrain, explore the full range of sprockets and chains available for your bike by visiting the SUNSTAR website at sunstar-braking.com. Need help selecting the right parts? Just ask!