Bicycle Braking Performance Testing and Analysis 2020-01-0876

The goal of this study was to determine bicycle braking performance, while considering different brake designs and applications. Eight bicycles were used to perform brake-to-stop tests: two full suspension mountain bikes, two hybrid bikes, one beach cruiser, one BMX bike, one road bike, and one single speed bicycle. The standardized brake testing procedure consisted of rear only brake application and both front and rear brake application. In order to maintain brake application consistency, a single rider performed all series of the brake tests at the same location, within a designated brake zone on dry asphalt. The tests were performed at initial velocities of 11 to 21 mph. For each test, the rider accelerated to the test speed and, upon entering the brake zone, applied maximum braking effort while maintaining a natural upright position in order to minimize lean. The associated skid marks deposited from wheel lock-up were verified, measured, and documented onsite. Bicycle wheel lock-up was verified if needed via video analysis. The bicycles’ deceleration rates were measured with a Midé Slam Stick X accelerometer, VBOX Sport, and calculated from the deposited skid marks. The deceleration rates measured using the Slam Stick X ranged between 0.40 - 0.71 g for front and rear brake application and 0.25 - 0.37 g for rear only brake application, across all bicycle types. Bicycles with rear coaster brake setups, such as the beach cruiser, braked at an average deceleration rate of 0.25 - 0.36 g. Bicycles with caliper and disc brake setups exhibited an average deceleration rate range of 0.27 - 0.36 g for rear only brake application. Additionally, the incipient lock-up phase was analyzed for distance travelled, speed change, duration, and kinetic energy loss.