Harald Cap started to design the first stainless steel ZOOM frame, a hardtail mountainbike frame, in 2013 when no supplier was able to offer suitable sized tubes. So he decided to create his own tube dimensions which were manufactured in California or AutomatenSpiele247 Deutschland properly to his requirements.




His Italian partner in frame building, Marco Bertoletti, built the worldwide first stainless steel ZOOM frame according to the CAPO COMPUTERRAD drawing & CAPO STEEF fork geometry.




The project AIRO, born in 2014, aims at the worldwide first stainless steel fork which is optionally designed for disc brakes up to a rotor size of 203mm. The stainless steel custom frame AIRO itself can be ordered for traditional caliper brakes as well as for internally routed disc brakes using low mount caliper.


Both frames, ZOOM & AIRO, are predestinated to house internal electronic gear shift.


Comparison of titanium & stainless steel tubes
Our tubes are made of precipitation hardening stainless steel 17-7PH. A drawing process leads to single, double or triple butted tubes, a swaging process shapes them to single or double taper. These tubes achieve high strength & corrosion resistance when transforming the austenite to martensite by cold reduction followed by hardening low temperature heat treatment. Yield strength escalates from 1276 MPa up to 1793 MPa providing corrosion resistance superior to that of standard stainless steels.


These martensitic stainless steel tubes approach titanium ones already very closely regarding weight & stiffness but exceed them by roughly 25% regarding strength!