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Eccentric Bottom Bracket vs. Sliding Dropouts

Eccentric Bottom Bracket vs. Sliding Dropouts

Introduction- Eccentric Bottom Bracket vs. Sliding Dropouts

What Are Eccentric Bottom Brackets?

Eccentric Bottom Brackets (EBB) add tension to our bike’s chain, in place of a derailleur. As it rotates, it tightens the chain to the required level. The idea of this device is to maintain the desired chain tension in single-speed bikes.

Now, as you read this, it may look like a straightforward thing to do. But, how do we use an EBB? Once installed, you need to loosen the bolts and look for the desired chain tension. When achieved, you just have to tighten them back again.

What Are Sliding Dropouts?

Sliding dropouts are also a way of tightening the chain. For single-speed bikes, this device adjusts the tension using a single bolt. This mechanism pushes the axle to the rear, and as it is fastened, so is the chain.

Adjusting a sliding dropout is quite different from EBB. You just need to change the drive and brake side until the wheel is straight. Check the tension is the desired one, and repeat the process until you are satisfied with the results.

Pros and Cons Of Eccentric Bottom Brackets

So, the main question here is: why do we have two completely different systems that provide chain tension? Let’s ride through this brief pros and cons, and check the main advantages and disadvantages of each device.

EBB’s don’t need you to straighten up the wheel. In other words, it won’t be altered while adjusting it, so there is one less thing to bear in mind. They also provide the possibility of moving it in either direction. Easy installation and use are also important benefits.

On the downside, this type of device is quite big, which makes it difficult if you need to add any other thing to your hub. Some bikers have also claimed to hear a creaky sound when riding in wet weather. In addition, frequent adjustment may wear it off, so it might need to be replaced earlier than expected if you tend to make changes to it.

This video shows the main features of an EBB and how to adjust your chain tension (Credits to First Components):

Pros and Cons of Sliding Dropouts

Sliding dropouts have an advantage in not being that big, so size and weight won’t be an issue. The creaky sound of EBB’s is not present, and we know how much we hate that constant noise while trying to have a beautiful, relaxing ride. Frequent adjustment hasn’t been an issue in this case, too.

Yet, as you might imagine, some of EBB’s advantages translate into disadvantages of sliding dropouts.

Installation is not that simple, as you need to check that your wheel is straight. They are not as versatile as EBB’s, so the possibility of moving them is not present. Plus, over-torque may bring severe issues to your frame.

This video has done a great job in explaining the features of dropout systems (Credits to Cobra Framebuilding):

Conclusion – Eccentric Bottom Bracket vs. Sliding Dropouts

As you can see, both EBBs and Sliding Dropouts have their pros and cons, so make sure to consider both sides of the coin when making your decision.