What Does a Bigger Sprocket Do on a Dirt Bike?

by Claire Peters 6 months ago in motorsports

In the end, every rider needs to find the perfect ratio to meet his or her riding goals.

What Does a Bigger Sprocket Do on a Dirt Bike?

When it comes to having a dirt bike, maintenance is key. A well maintained bike goes faster, runs more smoothly, and lasts longer. Part of maintaining your dirt bike is learning how to change up your parts when they wear out, or when you’re looking for different performance.

Sprockets and chains have everything to do with your bike’s gear changes, speed, and ride feel. Here’s what you need to know about how they affect your bike, so you can make a decision about sprocket size the next time you do some maintenance.

Gear Basics

The gears on your dirt bike are what take the power from the engine, and make the wheels move. You have sprockets in both the front and in the back, and they have a ratio of teeth when compared with one another. Whenever you change the dirt bike sprockets, you end up changing this ratio.

When the ratio changes, the bike will behave differently. The way it connects with the ground and the way it uses its power depends on both the gears and the ratio between the front teeth and back sprockets.

Why It Matters

Not every dirt bike track is the same. If you want to ride on the street, you’ll want a certain type of performance out of your bike. If you want to ride in deeper dirt, you’ll need a different ratio. Different tracks will be easier to ride with different sprocket ratios.

The same gear ratio and sprocket size that works beautifully on tight curves in the dirt and gives you incredible traction and control will make you slow, sluggish, and unresponsive on the tarmac or a sandy straight away.

In general, the higher the ratio of front to back gears, the faster the bike will go and the better it will perform on the street or on sandy terrain.The lower the ratio is, the more torque you get and the better the bike will perform on deeper dirt terrain or around tight curves.

What does this mean for sprockets?

It’s always a good idea to change your sprockets and chains at the same time. Whenever you do, you have the option to change up the ratio of teeth between the front and back. If you want fast acceleration and more power in your back end for turns and deep dirt, you’ll want to use a larger sprocket in the back and a smaller one in front.

If you want a higher gear ratio and a better top speed for smoother terrain, you’ll want a large sprocket in front or a small sprocket in the back. In general, it will make more difference to the feel of the bike if you change the front sprocket size than it will if you only change the back.

Size Ratios

The general rule is that for every tooth on the front sprocket that you’re adding or subtracting, you’ll change the rear sprocket by three to four teeth. If you want to make a very small change that will produce a noticeable difference on the street, without compromising your off-road ride, add or take away one or two teeth on the back sprocket only.

Rear sprockets come in sizes from 30 to 60 teeth, while front sprockets come with 10 to 16 teeth. You can find your ratio by calculating these together. Use a ratio card to find the sprocket sizes you want. Your gear choice is a highly personal decision, so what works for you might not be best for someone else.

Don’t forget that the ratio is always the most important thing. By using a larger sprocket, you can change your bike’s performance. However, the size of the sprocket isn’t what ultimately makes the difference, it’s the ratio change that is crucial.

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