Mudguard Guide
Updated: 20th October 2021
Why use mudguards?
Mudguards help keep you warm and dry in the wetter months while also protecting your bike from mud, grit and spray.
This can dramatically cut down any maintenance needed to your bike through the winter. For commuters they are essential, road cyclists will enjoy the dry, comfortable feeling while not spraying any friends behind, and mountain bikers will cut down spray and mud to the face, eyes and back. Warm and dry cycling is simply more enjoyable, meaning you can ride longer and more often through the winter.
What type of mudguards will fit my bike?
For commuters, road riders and general cyclists the first thing to look for are eyelets or attachment points on your frame and fork. If you have the eyelets then a traditional full-length mudguard can be fitted. There are different widths of mudguard to suit your tyre width. There are many combinations of wheel size and tyre width available, look on your tyre for these sizes and choose the appropriate option.
Fork eyelets
Frame eyelets
What size?
The size of the mudguard needed for your bike will depend on your wheel size, and tyre size. Almost all tyres will show a series of numbers written on the sidewall of the tyre. MTB tyres tend to use inches, while road tyres use a different measurement system based on mm.
For example, an MTB tyre might say 27.5 x 2.40, while a road tyre might say 700 x 23. The first number is the wheel size, the second is the width of the tyre (inches for MTB and mm for road). The mudguard must be a little wider than your tyre so it does not rub. Full-length mudguards will also need enough clearance in the frame and forks. For example, a 32c wide road tyre is 32mm wide, so a mudguard that is 35mm wide would be ideal.
MTB tyre
Road tyreMudguard sets
Full-length mudguards
If your bike does have eyelets then a full-length mudguard set can be used, these offer the best protection for bike and rider from the elements. They do take a little longer to fit as they are so robust. Some longer types have additional mud flaps and reflectors built in.
To find the right size, simply select the option that suits your wheel size and tyre width. As all bikes are a little different, full-length mudguards are adjustable. This does take a little time, and sometimes the stays must be cut to length. But once in place, full-length mudguards will offer the best wet-weather protection available.
Popular full-length mudguards
Clip on mudguards
Performance road and hybrid sport bikes with no eyelets for mudguards can use a clip-on type of mudguard set. Most performance based bikes that do not have eyelets will have very tight clearance between the frame/fork and tyre that does not allow a full-length mudguard. While clip on mudguards offer a lot of protection, they are limited by the performance nature of the bike. Clip on mudguards simply strap around the fork leg and rear seat stay to offer a good amount of protection from the elements.
Popular clip-on mudguards
Mountain bike mudguards
While full-length mudguard sets are the prefered option for road and hybrid riders, mountain bikers will use one of the many fork-mounted front mudguard options to keep the crud at bay. Rear mudguards are also available for all types of bikes, including full-suspension mountain bikes.
Front mudguards
Basic front mudguards
There is a large range of basic front mudguards available. These mudguards come as a flat piece of thin plastic that is then bent to shape under the arch of the fork and held in place with some zip ties or Velcro strips.
While not giving full coverage, they do keep the spray away from your eyes and protect the delicate seals of a suspension fork from grit and grime. Many companies manufacture this style of mudguard, some even use recycled plastics. They are inexpensive, very light, easy to fit and are compatible with most forks found on mountain bikes, hybrid and gravel bikes.
Longer Fork Mounted options
In recent years a new style of front mudguard has been available. This type is longer and provides more coverage than a basic mudguard. Fitting similarly to a basic mudguard, they are held in place with zip ties or Velcro straps. This longer type is more sturdy in its construction and material, though still flexible and designed to break away before damaging your forks in a crash.
This longer type deflects spray down and away from the riders face and upper torso. Some have a lip on the very front that catches any spray that would be flung forward off the tyre. While these are a little heavier than a basic mudguard, the extra coverage is worth the weight penalty.
Bolt-on Mudguards
Most modern mountain bike suspension forks from the likes of Rock Shox, Fox, DVO, and Ohlins have threaded holes in the back of the fork arch. There is now a range of bolt-on front mudguards that bolt directly to the fork bridge. The main advantage is rattle-free use, and with no zip ties, it removes the risk of rubbing the paintwork of your forks.
The mudguard design is very similar to the longer front-mounted options listed above, but they do not use zip ties or velcro straps to attach. Please check the description of the mudguard for compatible forks. Some fork and mudguard combinations also require an additional adaptor plate for bolt-on use.
Downtube Mudguards
Downtube mudguards have been around for quite a few years. Popularised by Crudcatcher in the early '90s, they are a simple solution for keeping mud and grime away from your face and upper body. Attaching to the bottom of the downtube using rubber bands or straps, they are easy to install and compatible with almost any bike that has a traditional triangular frame shape.
While they are easy to install, widely compatible, light and inexpensive, they have a downside of only being effective when the tyre is directly in line with the mudguard. Once you turn the front wheel, there is no more protection. A downtube mudguard can be used in conjunction with other styles for additional protection.
Headtube Mudguards
Steerer mounted front mudguards have an expanding bung to secure the mudguard to the bike. The bung is inserted inside the steerer tube from underneath the fork crown. Tightening the bolt expands the bung to hold the mudguard in place. This style of mudguard is easy to fit and compatible with most bikes that use suspension forks.
A steerer mounted mudguard is great for leisure cyclists though mountain bikers might not find it as secure on very rough terrain as other types. Care needs to be taken when selecting the mudguard for your bike. Please measure the internal diameter of your fork steerer and check against the product description to ensure compatibility.
Popular front mudguards
Rear mudguards
A full-length mudguard will give the most protection, but the traditional style needs attachment points on the frame and forks. This style is suited to recreational road and hybrid bikes.
If your bike doesn't have the mounting points for a full-length mudguard set, there are still plenty of other options available.
Frame mounted
Mountain bikes, especially full-suspension frames, will not have any mounting points and eyelets for traditional full-length mudguards. A traditional mudguard is not very good off-road as they rattle on and rub on rough terrain. Luckily, there are rear mudguards that securely attach to the frame using zip-ties or Velcro strips.
This style is the most effective at keeping the crud away. The closer the mudguard to the tyre, the less chance any mud or water can escape and cover your body and bike. Once mounted tightly this style is solid and is the best for mountain bikers.
Seatpost mounted
A rear mudguard mounted to the seatpost is secure and effective. A universal design that uses a clamp to mount around the seatpost. There are a few different designs but all work in a very similar way. The closer the mudguard can be to the tyre, the more effective it is at stopping the spray from being thrown up by the back wheel.
This is a universal design, so long as your bike has a saddle height higher than the top of the back wheel and there is some exposed seatpost for the clamp then this type of rear guard will fit. A frame-mounted type will be best for mountain bikers who ride rough terrain, but for the majority of leisure cyclists, a seatpost mounted mudguard will be effective and easy to install.
Saddle mounted
While not as effective as a frame or saddle mounted mudguard, a simple saddle mounted mudguard has many advantages. Very easy to install, this type of mudguard fits between the saddle and the seat clamp. It slots neatly around the saddle rails with a folding design to lock into place. You will need a traditional saddle that has two parallel rails to fit this type of mudguard.
There are wider versions to give more protection and narrower options for those with thin road bike tyres. This design, though slight, will keep the worst of the spray away from your saddle and bottom. They are very light, not expensive, quick to install and very modest when riding. You will barely notice a simple rear saddle mounted mudguard.
Popular rear mudguards
Summary
Mudguards are essential to keep riding through the winter, with many different types there is a wet weather solution to almost every bike. Road cyclists will be able to keep training through the worst of weather and riding friends appreciate not riding through the spray normally thrown up by the rider ahead.
Your bike will thank you and your winter clothing will last longer. Commuters will find mudguards essential, and mountain bikers will find it easier to keep warm and dry through the most extreme conditions.
The wheel size and width of the tyres fitted to your bike determines the size of mudguards needed. For example, a wheel that is 700c with a tyre of 32mm width will need a mudguard made to accommodate those measurements.
There are many different types of mudguard. If your bike has eyelets near the front and rear dropouts, along with attachment points in the fork crown and seat stays then full-length mudguards could be fitted. For bikes without these attachment points, there are other clip-on options.
Full-length mudguards have stays that attach to the eyelets on the front and rear dropouts. The front will also attach at the fork bridge. The rear will also mount at the seat stays and often behind the bottom bracket in the centre of the chainstays.
Mudguard eyelets are small threaded holes near the front and rear dropouts. These allow a bolt to be used to attach the stays of the mudguard.
A traditional road bike with rim brakes and narrow tyres (around 25mm) will often not have the clearance or mounting points needed for full-length mudguards. There are various clip-on options available for road race bikes.
When the mudguards are fitted correctly they should not rub on the tyres at all. This means that they will not create any friction against the tyre and will not slow you down in any way.