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Why Does My Rear Bike Wheel Wobble, and How Do I Fix It?

Raleigh rsw bicycle coaster brake sturmey archer tcw iii 1969

Cycling can be a huge amount of fun and a great activity to make a habit. It can help you stay in shape, get fit, and make many new friends. Having a bike isn’t always easy, and from time to time, you might need to give it some attention. What’s incredible about bikes is typically, a lot of the work can be done at home with basic tools.

A common issue many cyclists have is a loose rear wheel. This isn’t just annoying but can be unsafe and, if left too long, be a costly repair. In this article, we’re going to tell you why rear wheels wobble, why it’s vital that it’s seen too quickly, and how to fix it.

Why Does My Rear Wheel Wobble?

Hand touching a rear bike wheel

A rear wheel wobble is a common problem on many bikes, and more than likely, if you have been cycling for a while, you would have experienced it. The interesting thing is it can happen for many different reasons, such as too much wear or you might have damaged your bike. Here’s what might be causing your rear wheel to wobble.

The rear axle might be loose

The most common issue many people find who have a rear wheel wobble is a loose axle. It’s an easy mistake to make by not tightening up your axle enough, and this will cause the rear wheel to wobble.

The rear axle might be broken

If not loose, you could have a broken rear axle. A broken rear axle can come undone over time or just not apply enough pressure on the frame to hold the wheel in place, causing it to wobble either when still or being ridden.

The wheel might not be true

If when you’re riding, your wheel wobbles, there’s a strong chance your wheel might not be true. If you don’t know what true means, it means straight. So because your wheel isn’t straight, it is wobbling side to side.

The bearings might be loose

On the hub of a wheel, you will find bearings. On older bikes, they are loose and come in what they call a cup and cone system. On newer bikes, they have cartridge bearings that are sealed. When bearings start to fatigue, especially the cup and cone, the wheel starts to come loose, and although it might be true and straight, it can wobble side to side.

Why is It Vital to Fix a Rear Wheel Wobble?

A rear wheel's close up shot

If your wheel is wobbling, there is a problem, and it will need seeing to sooner rather than later. A rear wheel wobble might not be much at first, but the longer you leave it, the worst it will get. It can eventually end up damaging your frame or getting jammed. This can be annoying but also very dangerous.

How Do I Fix a Rear Wheel Wobble?

A man holding his bike
Photo by Priscilla Du Preez on Unsplash

So you might be reading this because you have a rear-wheel wobble. Not to worry. It is a pretty easy thing to fix. We will start by identifying the problem and then give you the solution to fix it.

Bent Wheel

The first thing we need to do is identify why the wheel is wobbling. You are going to first want to get the bike in a stand and then spin the wheel. If it runs smoothly in the bike but wobbles, then you have a bent wheel.

To fix a bent wheel, you will need to use a spoke key to true it. I would highly advise following a video on youtube on how to do this or taking it to your local bike shop if you are unsure. Truing a wheel can be quite challenging and does take some practice. You can attempt this yourself, but we recommend getting an expert to do this.

Loose or broken axle

To check the axle first, remove it and visually inspect it for any damage. If it looks fine and all the threads are not damaged, insert it and tighten it back up. If it still wobbles, try changing the axle; if that fails, you might have a broken axle.

The best and easiest way to fix a broken or loose axle is just to straight replace it. They cost about $10 for a pair and will give you years of great service. We would even go to the extent of replacing them with locking axles, as it can save your wheels from getting stolen.

Loose bearings

Now we come to loose bearings. You first need to check that you don’t have a bent wheel or a broken axle. After that, you’ll want to get the bike on the floor or in a stand, then grab the back wheel and push it from side to side. If it feels loose and clunky, then the bearings need work. If it feels solid and runs smoothly, then the bearings are ok.

On sealed bearings hubs, you will need to replace the cartridges, which is a simple job. On cup and cone, you will need to take the hub apart, clean the bearings and hub, check for any visible damage, then regrease and tighten up, so it runs smoothly and doesn’t have any play.

Should I Fix My Bike Myself?

Man repairing a rear bike wheel

Fixing your bike yourself can be a lot of fun, and learning how to fix a bike will continually help you throughout your cycling hobby. If you feel confident in your ability, we recommend having a go at fixing it yourself. If you are unsure, we recommend fixing it with someone who can help or taking it to a bike shop.

Conclusion

Having a rear wobble on your bike is not ideal and, in the long run, could cause you and your bike some big issues. We recommend getting it fixed as soon as possible, and if you can do that yourself, even better. If you’re unsure, take it to a good mechanic at your local bike shop.

Robbie Ferri

Robbie Ferri

Robbie Ferri is a cyclist living in Norfolk in the UK. From breaking World Records to competing in some of the hardest Bikepacking races in the world he is not shy of riding the miles. He has been lucky enough to work at some amazing shops and with some big cycling brands. Alongside this he even had input in designing bikes and has also been a tester for unreleased products. He absolutely loves cycling and believes everyone should have a bike.