CHACHA Bottom Bracket

CHACHA is a press fit bottom bracket designed for cranksets with an integrated 24 mm crank spindle. Its composite construction keeps system weight low while offering defined compatibility across city and trekking, mountain, and racing bicycle applications.

Composite cups, a composite sleeve and 2RS ball bearings form the core of the system. The cups cannot corrode, supporting straightforward assembly and disassembly. Different spacer dimensions and two ball bearing options give you additional flexibility when defining the final configuration.

For frame integration, CHACHA fits bottom bracket housings with a 41 mm diameter and widths of 86 to 92 mm. 

Key Benefits at a Glance

• Lightweight Composite Construction: CHACHA uses cups made from PA6-GF50, a polyamide 6 composite reinforced with 50% glass fibre for high stiffness and strength. The composite cups, sleeve and diameter reduction rings support a lightweight, defined press fit configuration for 24 mm crank spindles.

• Corrosion-Free Composite Cups: The composite cups cannot corrode. This simplifies handling during assembly and disassembly compared with metal cup solutions where corrosion can affect the interface over time.

• Flexible Bearing Configuration: Choose between ball bearings manufactured in China with single-lip sealing and ball bearings manufactured in Germany with double-lip sealing. This lets you align the configuration with your technical and sourcing requirements.

• Flexible Frame Integration: Compatibility with 86, 90 and 92 mm bottom bracket housing widths, together with different spacer dimensions, gives you flexibility when adapting CHACHA to the final frame and crankset setup.

• Tested Across Multiple Bicycle Categories: CHACHA has passed the required ISO 4210-8 certification tests for city and trekking bicycles, mountain bicycles, and racing bicycles using a market-standard crankset.

• Eco-Design Considerations: CHACHA’s composite components contain 30% recycled material and have a 50% lower carbon footprint than THUN’s standard composite material. Production and assembly also involve cooperation with a vocational rehabilitation workshop for people with disabilities.