The basic principle is the adaptation of the frame using several variants of 3D printed inserts — thanks to this solution there is no compromise. We’ve eliminated the use of braze-ons, which are seen commonly on other frames. The inserts are fitted into stainless steel segments, which are manufactured by CNC milling. These segments are silver-brazed to the frame to avoid excessive thermal deflection.
The inserts are manufactured using advanced MJF technology on Hewlett-Packard 3D printers. This technology involves the gradual sintering of powder layers, before the product is removed from the powder. A tough, black-dyed material, Polyamide PA12, was chosen for the production of the inserts. The part has 100% infill with low porosity, and the individual layers are imperceptible to the eye.
The input, through which the cable routing is introduced to the frame, is an insert in the down tube (DTT). We produce DTT inserts in four variants – mechanical, electronic (Di2, EPS), wireless shifting (Etap) and also in a variant for 1X mechanical shifting.
An essential functional element is the bottom bracket guide. The design of the frame with the T47 standard enables sufficient space to guide the cable routing and cables inside. This hole in the frame also serves as a service window, which allows the cable to be replaced without having to remove the bottom bracket.
The output of the bowden cable to the derailleur is solved through the rear cast dropout developed by us. Dropout is hollow and can be sealed with a round grommet. The rear brake cable port is incorporated by way of an interchangeable insert in the left chainstay.
All development took place in-house at Repete, verification of the component design was provided by FDM 3D printing. The locations of individual structural segments were chosen by determining the least possible influence of the structural properties of the frame. The frame was tested according to the European standard ČSN EN ISO 4210-6 on fatigue testing equipment. Subsequently, the solution was tested on prototype bikes.
