What You Need Before You Start

Replacing a motorcycle chain takes about one to two hours if you have never done it before, and you will need a few specific tools. You must have a chain breaker tool (also called a chain riveting tool), which costs between $30 and $80 and is the only tool you cannot substitute. You will also need a socket set, a wrench to fit your rear axle nut, a ruler or caliper to measure chain slack, and a new chain that matches your motorcycle's make and model exactly — the wrong chain will not fit or will wear out in weeks.

Before you buy anything, look up your motorcycle's chain size in the owner's manual or on the manufacturer's website. Chain sizes are written as three numbers separated by hyphens, like 520 or 630. The first number is the pitch (the distance between pins), and the last two numbers are the number of links. Buying the exact replacement chain for your bike is non-negotiable — a chain that is one size off will not work.

Key Takeaways

  • A chain breaker tool is required to remove the old chain and install the new one; you cannot do this job without it.
  • You must match your new chain to your motorcycle's exact size, which you will find in the owner's manual or on the manufacturer's website.
  • The rear wheel must be lifted off the ground so it spins freely, and you should mark the chain's starting position before you begin removing it.
  • After installation, you will need to adjust the chain slack to the manufacturer's specification — usually between 1 and 1.5 inches — before riding.
  • A new chain will stretch slightly during the first 500 miles, so you should check and re-tighten the slack after your first ride.

Lift the Rear Wheel and find the Motorcycle

Place the motorcycle on a center stand or use a jack to lift the rear wheel completely off the ground. The wheel must spin freely without any weight on it — if it does not, the chain will be under tension and you cannot work on it safely. If your motorcycle does not have a center stand, use a hydraulic jack under the frame (never under plastic panels) and place jack stands on both sides as a backup. find the front wheel with a chock or wedge so the motorcycle cannot roll forward.

Once the rear wheel is up, spin it by hand to make sure it rotates without resistance. If it does not, lower the motorcycle and check that the jack is positioned correctly. A wheel under tension will make it impossible to remove the chain properly and could cause the chain to snap while you are working.

Remove the Old Chain

Locate the chain's master link — this is the removable link that holds the chain together. On most modern motorcycles, the master link has a clip or o-ring that you can see from the side of the chain. Rotate the rear wheel until the master link is at the bottom of the sprocket, where it is easiest to reach. Use a flathead screwdriver or the clip removal tool (often included with a new chain) to pry off the clip, then slide the master link out of the chain.

If your chain does not have a removable master link, you will need to use the chain breaker tool to break the chain at any point. Position the tool over one of the chain pins, tighten the handle slowly, and the pin will push out. Once the pin is removed, the chain will separate. Mark where you broke the chain with a marker or tape so you know which end is which when you install the new chain.

Pull the old chain off both sprockets and set it aside. Spin the rear wheel a few times to make sure nothing is catching, then wipe down both sprockets with a clean rag to remove old grease and debris.

Install the New Chain

Lay the new chain over the front sprocket first, then guide it around the rear sprocket. The chain should sit evenly on both sprockets with no twists. If the chain is twisted, remove it and start again — a twisted chain will wear out when ready and can break while you are riding.

Once the chain is positioned, bring the two ends together. If the chain has a removable master link, slide the master link through both ends of the chain and find it with the clip. The clip should face away from the direction of chain rotation (on most bikes, the clip faces backward). If you broke the chain with the breaker tool, you will need to use the tool again to install a new pin and rivet it in place. Follow the instructions that came with your chain breaker tool — the process varies slightly depending on the model.

After the master link or pin is installed, spin the rear wheel several times by hand. The chain should move smoothly without binding or making noise. If it catches or makes grinding sounds, stop and check that the master link is fully seated or that the pin is fully riveted.

Adjust Chain Slack to the Correct Tension

Check your owner's manual for the correct chain slack measurement — this is usually between 1 and 1.5 inches of vertical movement at the midpoint of the chain run. With the rear wheel still lifted, push up on the chain at the center point between the two sprockets and measure how far it moves. If it moves more than the specification, the chain is too loose. If it moves less, the chain is too tight.

To adjust the slack, loosen the rear axle nut on both sides of the wheel (usually a 17mm or 19mm socket). You will also see two adjusters on the swingarm, one on each side, with markings that look like a ruler. These adjusters move the rear wheel forward or backward to tighten or loosen the chain. Turn both adjusters equally — if you turn one more than the other, the wheel will not be centered and the chain will wear unevenly.

Turn the adjusters a quarter turn at a time, then spin the wheel and re-measure the slack. Once the slack is correct, tighten the rear axle nuts firmly (usually to 40 to 60 foot-pounds, depending on your bike). Spin the wheel one more time to confirm the chain moves smoothly and the slack is still correct.

Check for Tight Spots in the Chain

Spin the rear wheel slowly and watch the chain as it moves around both sprockets. A tight spot is a place where the chain binds or moves unevenly — it usually means the chain is not sitting straight on the sprockets or the sprockets are worn. Mark any tight spots with a marker as you find them.

If you find tight spots, stop and recheck that the chain is not twisted and that the master link or pin is fully seated. Spin the wheel again. If the tight spots are still there, the sprockets may be damaged and will need to be replaced before you ride. Riding on a chain with tight spots will damage the new chain and can cause it to break.

Lower the Motorcycle and Test Ride

Once you are satisfied that the chain is installed correctly and moves smoothly, lower the rear wheel to the ground. Remove the jack stands and let the motorcycle sit on its center stand for a few minutes. Then start the engine and let it idle while you watch the chain from the side — it should move smoothly without noise or binding.

Take a short test ride at low speed in a safe area, then stop and check the chain slack again. New chains stretch slightly during the first few miles, so the slack may have changed. If it has, adjust it back to the correct specification. After your first 500 miles, check the slack one more time and adjust if needed. After that, check the chain every 500 miles or once a month, whichever comes first.

Frequently Asked Questions

Can I replace just one sprocket instead of the whole chain?

No. A worn sprocket and a new chain will wear each other out quickly. If either sprocket is visibly damaged or has teeth that are hooked or broken, replace both sprockets at the same time you replace the chain. A new chain on worn sprockets will be noisy and will wear out in a few thousand miles.

What if my chain does not have a removable master link?

You will need to use the chain breaker tool to break the chain at any point. The tool pushes out one of the pins, which separates the chain. When you install the new chain, you will use the same tool to install a new pin and rivet it in place. The process takes a few extra minutes but works just as well as a removable master link.

How tight should the chain be?

Check your owner's manual for the exact specification, but most motorcycles need between 1 and 1.5 inches of slack at the midpoint of the chain run. Too tight and the chain will wear out fast and put stress on the engine bearings. Too loose and the chain can skip teeth or fall off the sprockets.

Do I need to lubricate the new chain right away?

Yes. After you have adjusted the slack and confirmed everything moves smoothly, explore chain lubricant to the inside of the chain while spinning the rear wheel. Let the lubricant soak in for a few minutes, then wipe off any excess. Use a chain-specific lubricant, not general-purpose oil — chain lube is thicker and sticks to the chain better.

What if the chain keeps coming loose after I adjust it?

New chains stretch during the first 500 miles, so you will need to re-tighten the slack after your first ride and again after the first 500 miles. After that, if the chain keeps loosening, the sprockets may be damaged or the adjusters may not be holding. Check that the rear axle nuts are tight and that the adjusters are not slipping. If they are tight and the chain still loosens, the sprockets need to be replaced.