W01 – CARBON FIBER BICYCLE RIM DEVELOPMENT PROCESS

W01 – CARBON FIBER BICYCLE RIM DEVELOPMENT PROCESS

Initiated in June 2022 with KOSGEB support, the W01 Carbon Fiber Road/Racing Bicycle Development Project was launched for sale as of March 2025, following the completion of all validation and testing processes. After an approximately 3.5-year R&D process, our aerodynamic, lightweight, and rigid carbon fiber rim, for which all intellectual property rights belong to MTI Kompozit, has been manufactured domestically in Turkey. The W01 Carbon Fiber Wheelset is designed as a high-performance “all-rounder” product that can be safely used in all training sessions and races throughout the four seasons.

Design and Manufacturing Technology

In the first stage of the project, the rim geometry—designed in accordance with ETRTO (European Tyre and Rim Technical Organization) standards—was prototyped using 3D printing technology, and tire-rim interface compatibility was verified. The Hot Press-Pressurized Core technique, a fast and cost-effective method for mass production, was chosen. Prior to the final design of the metal molds, a 75-degree cross-section of the rim was produced; this enabled the determination of appropriate consumables and the completion of the mandrel design processes, ensuring the carbon fiber attained the desired final form. The composite hot press machine, which possesses high temperature and pressure sensitivity, including its electronic control unit, was designed and manufactured from scratch by MTI Kompozit. The pre-preg carbon fiber fabrics used in the process were procured from KORDSA.

CFD (Computational Fluid Dynamics) Analyses

For the first time, comprehensive CFD (Computational Fluid Dynamics) analyses were conducted for the W01 rim hoops. Detailed micro-adjustments were made to the rim geometry to achieve maximum aerodynamic efficiency, utilizing the precise mesh structure created for the analyses and testing at various wind speeds.

Testing, Optimization, and Quality Control

Within the scope of the W01 project, a total of 168 complete rim hoops were produced and subjected to destructive testing until their limits were determined. The rim hoops were optimized based on 9 key parameters in accordance with DOE (Design of Experiment) principles: carbon fiber pre-preg type, carbon fiber weave and layup orientation, resin type, layer count, curing temperature, spoke bed strength limits, tire pressure strength limits, dynamic load resistance, and lateral and radial stiffness.

The produced prototypes were tested in accordance with TS EN ISO 4210-7:2023 “Cycles – Safety requirements for bicycles – Part 7: Wheel and rim test methods” and UCI (Union Cycliste Internationale) carbon fiber rim impact test specifications. All test rigs, with one exception, were designed and manufactured by MTI Kompozit in compliance with the specifications. Spoke tension tests were performed at the Mechanical Testing Laboratory of the Department of Metallurgical and Materials Engineering at Eskişehir Osmangazi University.

Aerodynamic Performance and Wind Tunnel Data

W01 wheelsets were subjected to wind tunnel tests at METU RÜZGEM, a first in Turkey. The 27,000 lines of data obtained from these tests formed the basis for all bicycle aerodynamic test projects, including the rider.

Our W01 rim's aerodynamic cross-section and internal geometry have been registered by the Turkish Patent and Trademark Office. Patent certificate number 2024/005042 is, according to TR Patent database records, the first registered patent in this field in our country. You can access the patent by searching with the patent number or company name via the link below.

https://www.turkpatent.gov.tr/en/research?form=patent

To contribute to aerodynamic efficiency, PILLAR’s PSR X-TRA WING 20 aero spokes were chosen. These spokes provide additional efficiency to the rider through the “sailing effect,” offering a net power gain of 0.21 Watts compared to the closest competitor. According to PILLAR Wing 20 wind tunnel test results (30 mph / 48 km/h), the energy expended during a 1-second sprint at 120 RPM pedal cadence decreased from 1,184 J in the competing product to 1,132 J with the WING 20. Power loss per wheel was 4.74 W in the competing product, while it dropped to 4.53 W with the use of WING 20, resulting in a net power saving of 0.21 Watts.

Technical Specifications and Configuration

W01 rims are the product of detailed engineering work that optimizes the balance between durability suited to Turkey's road conditions, low rolling resistance, and a 38mm profile depth for aerodynamic gain and weight. Thanks to the 25.4mm external rim width, maximum compatibility with both modern and traditional road/racing bike frames has been targeted.

Although the W01 rims are cured during the production stage to meet the heat and pressure requirements for Rim Brake usage, they are currently offered for sale only with a disc brake configuration due to constraints in the supply of sustainable, high-quality hubs.

Best wishes to our country and all our performance cyclists.