Featured Product: SlackSetter by Motion Pro

Regular maintenance of your motorcycle’s drivetrain is crucial to the safety and performance of the bike. Checking the chain slack is an essential, yet often overlooked drivetrain maintenance task. 

Any seasoned rider knows that chain slack is constantly changing, particularly when the chain and sprockets are new. Correcting chain slack enables optimum suspension performance, and adds to the longevity of all the drivetrain components.


Buy Motion Pro Slacksetter tool

Buy Motion Pro chain tools


Too Much Slack: Motorcycle will experience chain slap, which is the chain making contact with the swingarm. The chain can can derail from a sprocket and damage the engine casing.

Too Little Slack: The sprockets and chain will wear out quicker, and there’s an increased risk of the chain snapping.

Motorcycle chain tension finger measurement

Many riders rely on what’s known as the “three finger rule” when checking the chain slack. It happens when riders use only their fingers to measure the slack. Because chain slack length and finger sizes vary considerably, the “three finger rule” is highly inaccurate. This is where the SlackSetter Pro by Motion Pro comes in handy. 

Motorcycle chain slack measurement Motion Pro Slacksetter

It’s a simple tool that enables you to accurately measure chain slack in a matter of seconds. The Slacksetter Pro is inexpensive, compact and lightweight, so it’ll fit comfortably in your ride-along tool kit. As with all Motion Pro tools, the SlackSetter Pro is superbly designed with the user in mind. For example, the measuring scale can be rotated so it’s easily readable from any angle, and it includes scales for absolute measurements.

How to Measure Chain Slack with a SlackSetter Pro

Refer to your bike’s owner's manual to determine whether to measure the chain slack from above or below the swingarm. Also use the manual to find out the tolerances the chain slack measurement should fall within. 

Motorcycle chain slack measurement

Next, measure between the front and rear sprockets to find the midpoint, which is the point from where you should measure the chain slack. Make a mark on the swingarm for the midpoint so you’ll know from where to measure the chain slack each time. 

Measuring Chain Slack Below the Swingarm

Step 1. Place the fork on the Slacksetter’s sliding arm over the chain and hold the top of the tool against the underside of the swingarm.

Step 2. Push the tube down over the measuring scale to set the scale to zero.

Step 3. Keep the top of the tool pressed against the underside of the swingarm, and pull the sliding arm and the chain downward until the chain is under tension.

Motion Pro chain slack setter tool measurement

Step 4. Read the chain slack measurement on the Slacksetter’s measuring scale.

Motion Pro Slacksetter chain slack measurement tool

Measuring Chain Slack Above the Swingarm

Step 1. Place the fork on the sliding arm over the chain, and hold the top of the tool against the upper side of the swingarm.

Step 2. Push the tube up over the measuring scale.

Step 3. Pull the sliding arm up until the chain is under tension while keeping the top of the tool against the upper side of the swingarm.

Step 4. Read the chain slack measurement on the measuring scale.

The Slacksetter is just one of many Motion Pro chain tools available on Partzilla. Watch the videos below to learn more about some of Motion Pro’s other high-quality tools, including the chain alignment tool and sag scale tool

Motion Pro Chain Alignment Tool

Motion Sag Scale II Tool



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