MTB pedals: Flat pedals made of aluminium or plastic - advantages & disadvantages

Flat pedals made of plastic - away from the cheap image

Until a few years ago, plastic pedals were little more than disposable items. Manufacturers fitted cheap flat pedals made of simple nylon to their mountain bikes when they were delivered, so that the buyer could at least ride the first few metres on their new treasure. These would-be flat pedals were usually not really suitable for off-road use. The platform was too small and slippery, the pins tiny - if there were any - and the bearings and seals barely withstood the first tough ride in bad weather.

In the meantime, however, the tide has turned and there is hardly a manufacturer left that does not offer plastic MTB pedals in a wide range of colours. What has happened? What advantages do plastic pedals offer that even established manufacturers such as Crankbrothers or DMR are including plastic pedals in their range? We found out from Austrian pedal specialist Tatze and show the differences between aluminium and plastic MTB pedals as well as their advantages and disadvantages.

The price - a clear point in favour of the plastic flat pedals

Good aluminium pedals usually cost at least 100 euros or more. This is not only due to the significantly higher material costs, but also to the manufacturing process. Plastic pedals incur high one-off costs for the injection moulds. These must be properly constructed in order to guarantee high quality. The material for production is then relatively inexpensive. This enables high-quality pedals at relatively favourable prices. Our price-performance tip from the MTB pedal test in BIKE 10/2022the OneUp Flat Pedal Comp, costs just 49.50 euros >> available here.

Weight - high material usage puts pressure on the scales

While the plastic pedal is still clearly ahead in terms of price, the situation is somewhat different when it comes to weight. The material used - usually a mix of plastic reinforced with nylon, glass or carbon fibres - is actually somewhat lighter than aluminium. However, the plastic pedals lose this advantage due to the higher amount of material used.

Aluminium has a higher tensile strength. Here, the wall thickness above the bearings can be reduced to up to 1.2 millimetres. In comparison, the wall thickness of plastic must be around 1 millimetre thicker for the pedal to remain sufficiently stable. This is why flatter pedals can ultimately be constructed from aluminium.

But beware: although some plastic pedals have a flat pedal body, they have a raised section on the axle bearing that can press uncomfortably against the foot while riding.

Durability and quality - plastic is extremely stable

With the right material, plastic pedals are brutally resistant. Glass fibre or carbon composites score particularly well here. Plastic is also more elastic than aluminium and will therefore probably never break. A pin breakage can occur with both materials. In the case of aluminium, the pin is torn out of the thread, which is usually destroyed in the process.

Bearings and seals in pedals must be of particularly high quality. They are subject to enormous forces, especially when biking off-road. This is not always the case with cheap flat pedals made of plastic. High-quality industrial bearings on the outside and plain bearings on the inside have now established themselves as the standard. For better support, some manufacturers install a double industrial bearing on the outside, which also increases durability.

The seal must seal off access to the bearings and must not be able to move on the axle. Otherwise the way is clear for dirt and moisture - the killer for every bearing. In the best case scenario, the manufacturer offers a refresh kit with the corresponding bearings or even including the axles. This increases the service life of the MTB pedals and protects the environment.

However, the plastic pedals have a small disadvantage when it comes to handling. While mounting on the crank is no different from the aluminium models, replacing worn pins is often more complicated. In contrast to aluminium pedals, plastic pedals are not threaded for the pins for reasons of durability. A lock nut is therefore required for fastening, which increases the effort involved in screwing and makes pin replacement a game of patience.

Appearance - not just a question of taste

Of course, aluminium MTB pedals are also available in the most dazzling colours. However, they are usually anodised or powder-coated and this has one major disadvantage: in the event of hard rock contact, the bare aluminium is exposed under the paint and the pedals quickly look shabby. Scratches are also much more noticeable on shiny aluminium.

Flat pedals made of plastic, on the other hand, are completely coloured through and scratches and nicks are less visible. This means that the pedals usually look fresh for longer. And if the plastic pedals do look rancid: With a little cleaning agent and a cloth, they can be easily freshened up and then look almost like new again.

Our conclusion: Flat pedals made of plastic for mountain bikes

Their cheap image is therefore completely unjustified. Provided the quality is right, the inexpensive composite pedals can easily compete with aluminium platform pedals. With the numerous colour variants available, they are also a great way to pimp your own bike according to your personal preferences.

More about MTB pedals:

BIKE 10/2022 with 10 sets of plastic pedals in the test - Contents at a glance

Combination pedals for mountain bikes: click & flat

Pedal test 2021: Flat, Enduro, Race - 20 MTB pedals with & without click mechanism