A Comprehensive Guide To A MTB Rear Mudguard

Rear mudguards are very useful if you want to stop the mud from spraying onto your back when mountain biking on wet and muddy trails. You’ll know all you need to about a MTB rear mudguard and will be able to decide which is best for your bike.

Part 1: What Is A MTB Rear Mudguard

When the winter months are approaching, it’s common practice to attach a mudguard to your bike. The reason for this is that when weather conditions are bad, and the trail is left very wet and muddy, mudguards stop mud from spraying up onto your face and back.

A mountain bike rear mudguard, also known as a rear fender, attaches to the seat stays, seat posts, or the saddle itself, to hang over the rear tire. If it’s doing its job correctly, a rear mudguard will stop mud from reaching your back and seat. This will make for a much more pleasant ride, keeping you clean and dry throughout.

Many front mudguards can also double up as rear mudguards, but this is often a makeshift job. They may need trimming down to size in order to fit over the rear wheel correctly and perform their job effectively.

Part 2: When To Use A MTB Rear Mudguard

Mountain bikes, especially those with full-suspension frames, will not have any mounting points and eyelets in order to fit traditional full-length mudguards. This is a luxury that road and hybrid bikes more often have. If your mountain bike cannot fit a full-length mudguard, that’s when a specialized mtb rear fender can come in handy to save you and your bike.

It’s best to mount a rear mudguard when you’re planning to ride on trails with especially muddy conditions. Not just to protect your back spray with mud, dirt, and water, but also to protect your shock, linkages. A best rear mudguard will help to minimise cleaning between rides and maximise intervals between services.

Rear mudguards are certainly necessary when riding with friends, or if you are planning to join a mountain biking club. When riding with others, a rear mudguard will catch any mud spray that could otherwise hit the person riding behind you. If you are looking to join a mountain biking club, many will require you to have mudguards fitted for this very reason.

When riding on advanced and dynamic trails, a rear mudguard can sometimes become a hinderance. They can be vulnerable to damage when travelling at faster speeds especially, and can impede your freedom of movement on your mountain bike. In these instances, you may prefer to simply wear a pair of waterproof trousers.

Part 3: How To Attach A Rear Mudguard

Often the most effective rear mudguards are attached to the seat stays of your bike using zip ties, or can be clamped on using a quick release clamp. There are also models that work best when bolted on to your bike, which helps for stability but can make for a finnicky installation process. When attached to the seat stays, the mudguard will sit nice and close to the wheel, which allows for the most spray prevention.

So long as your bike’s saddle height is higher than the top of your back wheel, and there’s enough room on there for a clamp, attaching your mountain bike rear fender to the seat posts will also be effective. In this position, it will stop the worst of the mud, expect to get a little bit muddy on a trail in harsh conditions.

There are also saddle mounted mudguards, which is the least effective position being fitted so far above the rear wheel. They fit between the saddle and the seat clamp. Mudguards are to just keep your saddle and bottom clean and dry, and they do a good job at this. You will often find that your back is covered in mud after a bike ride, however. Follow the instructions provided by the manufacturer on how to fit your specific model for the best results, as mountain bike rear fenders do vary when it comes to the mounting process.

Part 4: What To Look For When Purchasing Rear Mudguard

The best mtb rear mudguard are durable materials. Meaning that they can take hits and even bend out of shape without breaking or losing their effectiveness. You’ll also want a mudguard that offers you and your bike as much protection from mud spray as possible. In this case, the longer the guard is and the closer to the rear wheel it is situated, the better.

Another factor that makes a good mudguard is whether it prevents itself from blocking up with mud on the inside. Some models have features that keep this from happening, meaning you will not have to clean them out between rides.

Not all mudguards are compatible with every wheel size. If you have very wide or tall tires, it’s a good idea to remain mindful of this and make sure the model you are purchasing will fit onto the rear of your bike nicely. You’ll want to have a bit of clearance between the fender and the rear wheel so that they are not rubbing against each other and causing unnecessary wear and tear.

mtb rear mudguard

An easy installation and removal process is also a factor that could influence your decision when purchasing a mudguard. Some are quicker and require much less effort to install and remove than others. So if you plan on fixing your mudguard to your bike before a trail and then taking it off afterward, make sure to get one that allows you to do this easily. 

Part 5: The Best MTB Rear Mudguards You Can Buy

Now that you know what to look for in a good rear mudguard. It’s time to dive into some of the best models you can buy on the market today.

Mudhugger FRX

 Price – £25

The FRX is a strong option for a rear mudguard. It’s 100% recycled black polypropylene allows it to endure a few hits. It also has brilliant longevity; you won’t have to worry about buying another mudguard for a very long time after purchasing this one.

The Mudhugger FRX was designed with the help of World Cup and Enduro World Series riders wanting maximum mud and spray protection. It comes at 450mm in length, which is certainly long enough to provide excellent protection from mud spray. This mudguard will keep you and your bike nice and clean during a ride. One of the best on the market for it.

This fender is widely compatible and will fit wheel sizes of 26”, 27.5” and 29”. You can mount them between the rear seat stay using zip ties. The installation process is quick and easy making for great removability. Without any standout features to protect against blockage, you may find yourself cleaning the inside of the Mudhugger FRX between rides to get rid of a build-up of mud.

SKS X-Blade Rear Dark Mudguard

 Price – £24.99

The compound composite material of SKS X-Blade Dark is high-quality, otherwise known as chromo plastic. This is a highly flexible material so you can trust that it will not break on you out of the blue for a long time. Even if you went out of your way to break it upon purchase you’d be in for a challenge! Unfortunately, it will not stay this flexible and unbreakable forever, as the material is liable to weaken over a number of years.

This mudguard mounts on the seat post of your mountain bike using a power strap that enables quick-release fitting. This is perfect for easy and secure mounting. The SKS X-Blade will not flap around in the wind and is easily removable. Compatibility is also good, with the mudguard being able to accommodate a variety of tyre sizes.

It will gradually become blocked with mud on the inside. It is not the worst problem to have with mudguards but is still worth noting.

Crud Rear XL Fender

Price – £19.99

The Crud Rear XL Fender is a great option for a rear mudguard. It’s the only one on the market that has a smooth anti-clog design, allowing for any mud caught on the inside to naturally escape, without you having to clean it.

It’s both long and wide, providing plenty of protection for you and your bike. Whatever conditions you are biking in, you can rest-assured that your clothes won’t require a deep clean when using this mudguard. From strong injection-moulded plastic, the Crud Rear XL Fender is mighty durable and will bend back into shape should it ever need to.

Your mountain bikes’ seat posts can be mount effectively by clamping above 27.5” and 29” wheels. Additionally, it stays in place during the roughest riding conditions thanks to its durable bracket. Make sure your bike is compatible if you’re looking to buy this one.

Topeak DeFender XC11 Rear Mudguard 

Price – £29.99

The Topeak Defender XC11 is a modern mudguard that does the job. Stopping mud from getting onto your back and into your bikes’ parts. It also has multiple pivots meaning you can adjust for maximum coverage. Also, be confident you’ll never get hit with loads of mud spray. The high-impact plastic construction is co-molded into a softer material at the trailing edge which improves durability. It is another brilliant long-term option on this list.

Using a quick-release clamp, it is a top-notch option for removability. You’ll be able to fit and remove it in a matter of seconds once you’ve been through the process a couple of times. The Topeak Defender XC11 is also compatible with a wide variety of bikes and wheel sizes.

Expect to have to clean this mudguard out periodically, as there is no special protection against blockage.

RRP ProGuard Rear Mudguard

Price – £25.99

Made with a polypropylene mix for great flexibility and strength. The RRP ProGuard Rear is an excellent option for years upon years of use. It’s very hard to break and will bend itself back into shape if involved in a collision. The flip side of these materials is that they make the surface layer soft. Thus it can scratch rather easily and tarnish the finish.

The RRP ProGuard Rear is fitted on to the seat stays using zip-ties. It’s a quick-fit that boasts exceptional tyre clearance; you won’t have to worry about it ever rubbing against your bikes’ rear wheel. It is also widely compatible, fitting above 26”, 27.5” and 29” wheel that are up to 3” thick.

The downside to this mudguard is that it isn’t very long. So it won’t protect you from getting splashed with mud on a rainy day and help to protecting your bike. You’ll be cleaning and servicing your bike less frequently with this mudguard installed.

This is another fender that will require some cleaning from within every now and again, as blockage will occur over time.


To summarise, mtb rear mudguards are a very worthwhile purchase. If you’re looking to protect you and your bike from mud spray. Fit them right for a more comfortable and enjoyable ride. As well as giving you a lot less cleaning up to do afterwards! When riding with friends, you can be confident that they will not be affected by the dirt and water that sprays up your rear wheel.

When choosing what rear mudguard to buy, it’s important that you make sure it’s compatible with your bike and rear wheel size so it can perform a proper job. The best mudguards are durable, easy to fit and remove, don’t require much maintenance, and offer you great protection from dirt on the trail.