Why the rim has a big impact on your bike
Whether road bike or city bike – the rim is much more than a simple component. It is the heart of the wheel and therefore plays a central role in the overall performance of your bike – and in a wide variety of areas: it influences the weight, stability, acceleration behavior and braking performance of your bike. In short, you can improve your performance by choosing the right rim – whether you're riding through mountain passes in the Alps, downhill mountain biking or on bike tours where particularly robust wheels are required.
Regardless of the intended use, the basic construction of a bicycle rim is always similar. The central element is the rim base. This is the part on which the tires are mounted. To the side of this are the rim flanks, also known as rim walls. They play an important role, especially on wheels with rim brakes. Another feature is the rim flange. This specially shaped protrusion on the inside of the rim flank helps to keep the tires in position on hooked rims. Bicycle rims also have spoke holes. These are located in the outer area of the rim and are responsible for attaching the spokes, which in turn connect the rims to the hubs. Each bicycle rim also has a valve hole for the tire valve.
Mountain bike, road bike and co. – rim types according to area of use
The area of use has a decisive influence on the design of a bicycle rim. This is particularly evident when comparing MTB and road bike rims. In the following, we present these two and other rim types in more detail.
Mountain bike rims – maximum stability for off-road riding
Robust rims with a wide rim width (see below) are ideal for mountain bikes, as they offer better support for wide, high-volume tires. In most cases, mountain bike rims are therefore made of aluminium. They also have an increased hole number for more spokes to further increase stability in difficult terrain. In terms of rim size, most MTBs roll on 27.5 inch (650B) or 29 inch (622 mm) rims. Smaller rims such as 26 inch or smaller can currently only be found on new children's and youth bikes.
Road bike rims – aerodynamic, light and fast
Road bike rims are narrower, as their focus is on aerodynamics and speed. High-profile rims with particularly high rims offer additional aerodynamic advantages. They are therefore often used in racing, but are more susceptible to crosswinds. In mountainous races, many racers opt for lighter, flatter rims. In training, on the other hand, more robust models tend to be used. The majority of road bike rims used today are 28 inch (622 mm). Smaller dimensions are rarely used, as the swinging effect is less pronounced as the size decreases.
Gravel rims – robust and versatile
Gravel bikes are becoming increasingly popular. The range of specific gravel rims is growing accordingly. They are a mixture of MTB rims and road bike rims: Robust, fast and occasionally aerodynamic. Depending on whether they are used for bikepacking or gravel racing. Many gravel bike rims are also tubeless-compatible. Like the range of use, the size of gravel rims also varies. The spectrum ranges from wider 27.5 inch rims to narrow 28 inch all-road versions and wide 29 inch models (also 622 mm), which also perform well on MTBs.
These other rim types are available
In addition to the sporty variants, bicycle rims are also perfectly matched to the respective purpose in many other areas. For everyday use – on touring bikes and the like – inexpensive and durable 28 inch rims make sense. Touring bikes, on the other hand, require robust rims that can cope with heavy luggage. In addition to 28 inch rims, you will also find smaller rim sizes such as 27.5 or 26 inch. Rims for compact or even folding city and urban bikes are a special case. Twenty inch rims are standard in the latter case. More stable rims are also used for electric bike wheels due to the higher wheel weights.
From design to material – rim types according to properties
Regardless of the intended use, bicycle rims differ in many other aspects. We have summarized the most important ones in the following connection.
Rim width, inner width and co. – the most important dimensions at a glance
The previous comparison shows that the dimensions of some bicycle rims differ significantly. If you want to buy a new rim, you should therefore know the following sizes:
- Rim diameter: Specified in inches. Indicates the wheel size for which the rim is intended.
- Rim height: Specified in millimeters. Basically, the higher the rim, the more aerodynamic it is – but also the more sensitive it is to crosswinds.
- Rim width: Specified in millimeters or inches. Determines how wide the rim is at the two outer points of the rim hooks.
- Inner width: Important for tire selection and tire fit. See the table below.
- Hole number: Determines how many spokes the rim can accommodate. This influences the stability and weight of the wheel.
The following table gives you an overview of the typical rim widths (inner widths) for MTB, road bike and gravel wheels:
| Rim type | Inner width |
| Road bike | 15 – 20 mm |
| Gravel bike | 20 – 25 mm |
| Mountain bike | 25 – 35 mm |
Wire bead tires, tubeless and more – The rim and the right tires
The type of tires you want to use has a big influence on the choice of your rims. We roughly distinguish between three groups: Wire bead tires rims, tubeless rims and tubular tires rims.
Wire bead tires – also compatible with folding tires – are the classic. Here, the tires with inner tube are fitted into the rim bed and held in place by the rim flanks. Rims for wire bead tires have a shaped rim flange to hold the tires securely.
Tubeless systems eliminate the need for an inner tube. Instead, the tires are mounted directly on the rim, forming an airtight seal. Tubeless rims must be designed to form a perfect gasket with the tires. This requires a precisely manufactured rim bed and special sealing components such as tubeless rim tapes and tubeless valves.
Hookless rims are also becoming increasingly popular in connection with tubeless. These do not have a hook on the rim flange, but a smooth side. The advantage is a simpler production process and wider, more stable wall thicknesses. Exciting: Due to their design, hookless rims create a rounder tire contour, which can improve the riding characteristics of the tire.
Another type of rim is tubular tires, also known as tubular rims. For a lengthy period, they were the ultimate in professional cycling. Unlike wire bead tires with a separate inner tube, the inner tube of tubular tires is sewn into the tire. These tires are mounted on special rims that do not have rim flanges. Instead, the tubular tire is glued to the rim.
Disc brake or rim brake – rims according to brake type
When selecting bicycle rims, the brake type also plays an important role. There are basically two types of brakes: disc brakes and rim brakes. Each type of brake places specific demands on the rim in terms of design and material.
Since the braking force of disc brakes is transmitted directly to the brake disc and not to the rim, rims for disc brakes do not have to be designed for the friction of brake pads. This opens up possibilities in terms of material selection and rim design. For example, carbon rims can be used without the special heat-resistant coating required for rim brakes. They can also be designed to be more aerodynamic.
With rim brakes, the braking force is exerted by brake pads that press against the rim flanks. Therefore, rims for rim brakes must have robust and heat-resistant rim flanks. Aluminum rims are popular for rim brakes, as aluminium has high thermal conductivity and therefore dissipates heat effectively. Carbon rims require a special coating to ensure heat resistance and reduce wear on the rim flanks.
Aluminum or carbon rims – the big material question
The previous point already shows it: if you are looking for rims for sporty use, sooner or later you will end up with the question of material. You can choose between aluminium or carbon rims. Both materials offer specific advantages and disadvantages that should be taken into account depending on your riding style, area of use and budget.
Aluminum rims are generally cheaper than carbon rims. They are also more durable and have a higher braking performance with rim brakes. Carbon rims allow for lighter, stiffer and more aerodynamic designs. Carbon is therefore the material of choice in many racing disciplines.
10 steps to the right rim – our buying tips
Now you are well informed about bicycle rims. To help you with your purchase, we have put together ten tips below to help you with your decision.
- Area of use: What type of bike should the rim be used on?
- Rim profile: Are you looking for an aerodynamic, high-profile rim for a road bike? Or would you prefer something robust for downhill and the like?
- Wheel size: For which wheel diameter should the rim be built? How many inches should it measure?
- Rim width: How wide should the rim be?
- Type of brakes: Should the rim be designed for rim brakes or disc brakes?
- Tires: What type of tires should the rim be designed for? Tubeless? Folding tires? Tubular tires?
- Material: Do you want an aluminum rim or a carbon rim?
- Eyelets: You can choose between non-eyelet, single eyelet or double eyelet rims.
- Manufacturer: Do you have special features regarding the manufacturer? At BIKE24 we stock rims from top manufacturers such as DT Swiss, Mavic or Newmen.
- Price: What price range are you looking for?
Buy bike rims online – our conclusion
As you can see, to find the right bike rim for your needs, you should think carefully about what you need beforehand. One thing is certain: Choosing the right rims is a crucial step in getting the best out of your bike.
In our online store, you will find an extensive range of rims for every type of bike – from mountain bikes to road bikes and touring bikes. Practical: In addition to rims, we also have all the other components you need for wheel building, such as bicycle hubs, spokes and nipples.