Road, all-road, gravel or mountain bike: the frame is the centerpiece of a bikepacking bike. Cyclists are often tempted to choose carbon for its lightness. But those who have actually experienced ultra-distance cycling know that lightness is not the dominant criterion.
When it comes to racking up the miles, whatever the terrain, cycling comfort is THE parameter that keeps you safe.
Every aspect of CHIRU BIKES design is aimed at maximizing the efficiency of your effort, while protecting your body from the aggressions of the terrain. Less tired, you go further. That’s why we’ve set our sights on titanium, but not only titanium.
Because our gravel, road and mountain bike frames are designed for ultra biking, our design approach combines maximum comfort and efficiency, which are essential conditions for endurance performance and adventure fun. With this in mind, we pay particular attention to the tube cross-sections used: no constant-section tubes on CHIRU frames!
The oval shape of our tubes stiffens the frame laterally, preventing it from losing too much power when subjected to lateral flexion due to pedaling forces.
On all CHIRU models, the three-tube sections connected to the bottom bracket are shaped by hydroforming or forming processes to maximize power transmission. The use of ovalized sections increases frame rigidity in one direction (greater width) and reduces it in the other direction (smaller width).
CHIRU frames combine a constant-thickness hydroformed downtube, a variable-thickness ovalized top tube and an oversized tapered head tube to deliver top-level directional precision.
To absorb impacts and protect the rider from vibrations, the chainstays and seatstays (rear triangle) are also ovalized to increase the frame’s passive “flex” in the vertical plane. Less subject to shocks and vibrations, muscles tire less quickly and energy output is higher to keep up with the distance.
The precision of digital machining, combined with the forming techniques we use, require a significant investment, usually reserved for medium production runs. Applied to small series production, this is quite rare, and results in an exceptional finished product quality that combines craftsmanship and industrial precision. The quality, reliability and finesse of the titanium welds on CHIRU frames are the fruit of over ten years’ know-how.