Parametric Bicycle Yoke

Author(s) Information

Colin Reay, California Polytechnic State University, San Luis ObispoFollow
Walter Minehart, California Polytechnic State University, San Luis ObispoFollow
Robby Harrigan, California Polytechnic State University, San Luis ObispoFollow
Jordan Olson, California Polytechnic State University, San Luis ObispoFollow

College - Author 1

College of Engineering

Department - Author 1

Mechanical Engineering Department

Degree Name - Author 1

BS in Mechanical Engineering

College - Author 2

College of Engineering

Department - Author 2

Mechanical Engineering Department

Degree - Author 2

BS in Mechanical Engineering

College - Author 3

College of Engineering

Department - Author 3

Mechanical Engineering Department

Degree - Author 3

BS in Mechanical Engineering

College - Author 4

College of Engineering

Department - Author 4

Mechanical Engineering Department

Degree - Author 4

BS in Mechanical Engineering

Date

6-2023

Primary Advisor

Amanda Emberley, College of Engineering, Mechanical Engineering Department

Additional Advisors

Andrew Kean, College of Engineering, Mechanical Engineering Department

Abstract/Summary

This report outlines the entire design, fabrication, and validation process of a parametric yoke design that addresses the packaging problem of the bottom-bracket chainstay junction in modern bicycle frames. The goal was to create an elegant, space-efficient solution that is accessible to the Cal Poly Bike Builders Club. The report includes documentation of the three-part fixture system, manufacturing process, and testing results for the yoke.

Our yoke design outperforms traditional round-tube weldments in torsional and vertical stiffness. Additionally, all manufacturing fixtures and machining operations function as intended, resulting in a finished yoke that meets all required tolerances in under an hour of machining time. The cost of manufacturing each yoke is under $20, making it affordable for Bike Builders' Club members.

The report provides detailed information on the testing conducted to verify the design prototype, including the methodology and results. Based on the findings, recommendations for design and process improvements are included for future reference. A user manual, project budget, test results, and other relevant project data are provided as appendices.

Moving forward, the project team plans to collaborate closely with the Bike Builders Club to ensure the successful integration and operation of the yokes in club member projects.

URL: https://digitalcommons.calpoly.edu/mesp/714