Denise Mueller has set the overall bicycle land speed record time at 183.9 mph. With that speed, she has smashed both her own women's record of 147 mph and the previous men's record of 167 mph.
Denise is an accomplished bicycle and motosports racer, a National Criterium Champion, and a 15-time National Champion, as well as a mother of three. Her coach, John Howard, a three time Olympian, set the men’s speed record 30 years ago.
Bicycle land speed records are set when the cyclist drafts behind a motor vehicle to minimize wind resistance. The vehicle is usually modified primarily by adding fairings to keep the wind off the cyclist who is behind it.
Verve was asked to assist in measuring power not only in the actual runs, but also in the lead up training. While supplying InfoCranks for Denise’s road bike was a simple matter, it was an entirely different situation for the Record Bike.
Project Speed used a standard InfoCrank M30 Power meter which has a 30 mm diameter alloy spindle with a compact 110 BCD spider. The bike was provided with a standard threaded bottom bracket shell which made it simple to install the standard BSA M30 Bottom Bracket.
However, as visible in the photo above, the chainring on the InfoCrank is actually on the left hand side of the bike to provide for the double gearing mechanism needed to achieve such high speeds. This required some modifications.
The InfoCrank Power meter
The power meter firmware which reads 256 torque messages per second needed re-calibration to be able to read “backwards”. This was done with a firmware upgrade and was the simplest part of the procedure. Three power meters were re-calibrated to ensure redundancy and fresh power meters for the record runs.
The Spindle and M30 BSA Threaded Bottom Bracket
The bike uses a standard BSA bottom bracket shell, which prevents reverse installation of the bearing cups. The thread directions are designed to prevent the cups loosening under operation. The right side of the bike has a right hand thread and the left side of the bike has a left hand thread.
Also InfoCrank’s bottom bracket incorporates a sleeve on the non-drive bearing that reduces its diameter to 28 mm, preventing reverse installation of the cranks.
To facilitate reverse installation of cranks, the bearings were replaced and the sleeve moved to the other side. Low friction Hybrid Steel-Ceramic bearings were used.
The pedal threads were not modified. Project Speed had a solution to the pedals operating on the opposite side of the bike without loosening.
We can be quite sure that the data recorded during the training, the racing and the 20 test and record runs was put to good use to achieve the Land Speed Record. Congratulations from InfoCrank to Denise, John, Shea and all the other important support from her team!