posted by George Cant
October 05, 2015

Just days ago, CUBE unveiled Andreas Raelerts Kona weapon, a new enhanced time trial bike frame, with aerodynamic optimization by Swiss Side. Now, with Swiss Side’s typical transparent approach, a rare look behind the scenes into the aerodynamic development process of Andy’s Kona aero package.
The Swiss Side aerodynamics team has been working closely with the Raelert Brothers since early this season, with one clear goal:
The absolute best possible aerodynamic performance for the 2015 Kona Ironman World Championship.
To achieve this target, Swiss Side let loose their entire arsenal of aerodynamic tools on Andreas Raelert. As always, a unique Formula 1 derived approach to the development was applied as follows:

1. Rider performance analysis for input to simulation.
2. CFD Study.
3. Competitor Analysis.
4. Equipment optimization.
5. Extensive wind tunnel testing to find the ULTIMATE package.

1. Rider performance analysis for input to simulation.
The way Andreas Raelert rides was analyzed in detail using data from him in competition, training, and importantly data obtained using Swiss Side’s Instrumented Bike. With this data, performance simulations could be made to see where the most time gains could be achieved and how best to optimize the aerodynamics of his complete bike and rider package.

Andreas Raelert on the Swiss Side Instrumented Bike

Typical data analysis of rider on Instrumented Bike
2. CFD Study.
The CFD data of Andreas Raelert with his setup on the Cube Aerium bike was analysed in detail to determine which areas could be improved to reduce the drag of both the bike and rider.

Lateral section showing low energy & separated flow regions.

Vertical section showing flow separations from cockpit.

Vertical section showing uncontrolled wake from rider leg and local flow separations in front brake – fork – frame region.
3. Competitor Analysis.
Competitor athletes and their equipment setups were evaluated. In conjunction Germany’s Triathlon Magazine (, Swiss Side wind tunnel tested leading competitor bikes in order to determine the aerodynamic benchmark to beat.

Cube Aerium Super HPC

New Canyon Speedmax CF prototype

Scott Plasma 5

4. Equipment optimization.
On the bike setup side, new parts were designed using CFD in order to improve the aerodynamic performance of the areas causing the biggest drag, and to improve the bike characteristics to better suit the rider.

New aerodynamics parts design for Cube Aerium Super HPC
On the rider side, the riding positions in which Andreas could competitively perform over the 180km Ironman distance were determined. In addition, a selection time trial suits, shoe covers and helmets were chosen for evaluation.

Andreas Raelert with two-piece no-arm triathlon suit

Andreas Raelert with one-piece short-arm triathlon suit
5. Extensive wind tunnel testing to find the ULTIMATE package.

In the final decisive step, an extensive wind tunnel testing session was done to evaluate all options and to find the ultimate aerodynamic package for Andreas. This included the evaluation of all newly designed aerodynamic parts, rider positions, apparel options and optimum race setup such as bottle positions.

Cube Aerium HPC with Kona package aero parts

Andreas Raelert with his optimized 2015 Kona aero package

Aero performance improvement of Cube Aerium HPC frame with Kona aero parts.
A significant step in aerodynamic performance was made on the Andreas’s current setup of his Cube Aerium Super HPC with the Kona aero parts. The base drag level was reduced by over 6% and further drag reduction of over 20% at higher yaw angles was achieved.
The Swiss Side aerodynamics team achieved their goal by making significant steps in aerodynamic performance on both bike and rider setups, ensuring that Andreas Raelert has the ultimate possible package for Kona. This will offer him a very important performance boost in his bid to take home the ultimate prize as winner of the Ironman World Championships.
In collaboration with Swiss Side, Cube has pushed to produce new optimized time trial frames which will be ridden by Andreas Raelert in Kona and by Michael Raelert for the rest of his 2015 campaign.
Follow all the action in Kona on October 10th, 2015!

Race ready Cube time trial frame with Swiss Side engineered aerodynamic improvements.

More info on the new Cube Time Trial Bike: