Bicycle saddles from the 3D printer put to the test: What can the new customised saddles really do?

If you have already found the perfect bike saddle and enjoy freedom from pain on your bike, consider yourself lucky! For most people, saddles don't fit properly or have never really fitted. Discomfort such as pressure points, numbness and rubbing are often annoying problems for many cyclists and the incredibly large selection of saddles can make the search for the right "contact point" frustrating. The "trial and error" approach can work, but is no guarantee. Only a few saddle manufacturers offer the opportunity to test different models extensively, and only a small number of dedicated bike shops offer such options to their customers.

The first step: first measure, then buy a saddle

The perfectly fitting saddle - this has been the main concern of the manufacturer Gebiomised for almost two decades. The Münster-based company was one of the first to use a pressure measurement film to analyse the seating position in action. "Dynamic pressure measurement on your own bike provides the best approximation of the right saddle," says the Managing Director of Gebiomized, Daniel Schade, who, in addition to his own saddle production, also passes on his measurement expertise to other manufacturers such as Fizik.

Ergonomics specialist SQlab uses the measurement of sit bone distances as the centrepiece of the saddle purchasing process, which is offered as a service by partner dealers. Their method aims to support the sit bones during saddle use in such a way that nerves and blood vessels in the sensitive perineal area are relieved and protected. In our experience, this technique can work well after a certain adjustment phase.

Next level: 3D-printed saddles directly from the manufacturer

3D-printed saddles are currently popular and manufacturers are promising an even more comfortable fit. Although the technology is quite time-consuming - it takes around 30 minutes to print a single saddle pad - and the printers required are still very expensive, the industry is investing in this new manufacturing process. One indicator of this is the increasing number of 3D-printed saddles from companies such as FizikSelle Italia or Specialized. They currently mainly offer their high-end models with a printed seat surface and a higher price, while they also continue to produce versions with the classic foam padding. The question therefore arises as to how the same saddle model with the same frame, shape and size changes or improves "just" by replacing the seat pad.

James Read, saddle designer at Specialized, argues that the 3D printed padding allows for more precise adjustment of the damping properties and the transition between soft and hard zones, compared to padding foam of different densities and firmness. This could, for example, lead to more effective cushioning and thus provide noticeable relief: By preventing the ischial tuberosities from pressing through the padding and thus protecting the neighbouring tissue from painful bruising. However, those who sit more "flat" - i.e. whose sit bones are less prominent - benefit less from the difference in the hardness of the padding.

>> Parallel to our comparison test here, we have already tested the new custom saddle concept from Fizik: Fizik ONE-TO-ONE bicycle saddle: completely customised saddle from the 3D printer

3D saddle and conventional bike saddle in the test

Using two models as examples, we tested whether and what differences are noticeable between saddles with traditional padding and 3D-printed padding. During a test ride on the road, our test rider, who weighs 70 kilograms and sits on his racer in his usual position, did not notice any significant differences in comfort. The most noticeable difference is that you don't - and can't - slip on surfaces with the printed honeycomb structure.

A laboratory test with pressure measurement film on the saddle and the bike clamped in the Smarttrainer provides deeper insights: the results show a strikingly even pressure distribution for both 3D saddles. While pressure peaks of up to 30 newtons per square centimetre occur with the standard saddles, they are only half that with the printed saddle pads. The 3D technology therefore makes a difference, and saddles with the same model designation can have different properties depending on the type of padding - traditional or printed. Whether they are compatible, however, remains a question of trial and error without prior analysis. 3D-printed saddles therefore represent an additional, albeit more expensive, option for increased seating comfort.

3D-printed vs. foamed: bike saddles from Fizik and Selle Italia in comparison

• Model: Vento Antares R3 Kium2 Model: Vento Antares R3 Adaptive Kium2
• Price: 149 Euro Price: 259 Euro
• Weight: 213 grams Weight: 234 grams

• Model: SLR Boost Ti 316 Superflow Model: SLR Boost 3D Ti 316 Superflow
• Price: 230 Euro Price: 360 Euro
• Weight: 164 grams Weight: 207 grams

The top models from various saddle manufacturers are available with both conventional and 3D-printed padding. In a specific test, we analysed the pressure distribution on the two models Vento Antares from Fizik and SLR Boost from Selle Italia The results were analysed on a test rider weighing 70 kilograms using a pressure measuring film. Apart from the fact that the 3D models are heavier and more expensive, they show a more even pressure distribution in the area of the sit bones compared to the traditional saddles.

With the 3D Antares from Fizik, the weight force of 15 newtons per square centimetre in the area of the sit bones is only half that of the classically padded Antares. The weight of the tester is distributed measurably and visibly more evenly over a larger area. However, whether this is perceived as more comfortable varies from person to person, as it shifts more weight to the front, usually more sensitive pubic area, which can often be perceived as uncomfortable, especially by women.

The SLR from Selle Italia represents a different aspect. With this 3D model, the pressure is distributed over a smaller area with less high peak values. Our test rider judged this to be positive.

>> We also tested a whole range of conventional saddles: From Tour to Race - 20 MTB saddles in laboratory and practical tests

Stereolithography: printing and baking bicycle saddles

Fizik, Specialized and Selle Italia all use the same production process for their bicycle saddles, namely stereolithography (SLA). In this technique, a container full of liquid photopolymer on a transparent base is processed by an SLA 3D printer. The resin is cured with a laser until the final mould is created. The still very flexible and sensitive saddle pad must then be cured (baked) for several hours under UV light and thoroughly cleaned.

At Posedla, a manufacturer of custom saddles, these are produced using the multi-jet fusion process, often referred to as the powder bed fusion process. Here, thermoplastic powders such as nylon or TPU are fused using heat in the form of infrared light. The finished saddle ends up in a bed of unused, reusable powder and is cleaned by suction and brushing. In contrast to production with liquid polymer, the saddle is ready for use immediately after cleaning and can be connected to the saddle base and the saddle cover without further treatment. The final cleaning is a further step on the finished product. According to the manufacturers, this production method offers the advantage that no costly tool changes are necessary for different moulds and no material is lost.

Final stage: The truly customised saddle for your bike

While the saddles tested are still more or less mass-produced products, the next sensible step towards a perfect fit seems to be customisation. The manufacturer Posedla has already taken this route. The Czech-based company offers customised saddles. The all-inclusive price of just under 500 euros for a completely customised saddle includes an individual measurement. Ondřej Janků, Head of Business Development at the company, is delighted with the business development. Several thousand saddles have already been sold since the company was founded in 2022.

From buttock prints to 3D printing

The path to a customised saddle begins with the creation of an online account on the Posedla website (posedla.com/en), where you enter individual data on your sitting position and riding style. Posedla then sends the "Smiling Butt Kit" to create a butt mould. Customers photograph this impression according to the instructions provided and send the images to the manufacturer via their online account. A software program uses this to calculate a three-dimensional model that is used to print the customised saddle. The Posedla concept currently utilises 3D technology for both measurement and production, which offers the highest potential for success from the saddle seeker's point of view. We were naturally keen to try out the service, but the delivery time of up to eight weeks after providing our own data exceeded our schedule for this article. We will submit a practical test of the customised saddle as soon as possible.

Customised saddle from Fizik?

While Specialized says it has no plans to produce customised bicycle saddles, Fizik is taking this step with the "One2One" concept. This is similar to that of Posedla, but differs in terms of measuring methods and distribution. The Italian company works together with selected support dealers, where data is collected by measuring pressure foils on their own bikes and processed together with other data in an app (from Gebiomised) for the saddle production template. We've already had our first customised Fizik One2One saddle made and tested it for a few laps.