How fast is a Brompton?

Published at : 23 Dec 2025

Find out the speed difference between a Brompton and a similarly price Road Bike.
We will assume both riders have the same weight, use the same tire type and apply the same power input. We evaluate the speed differential for casual riders as well as performance riders.

00:00 Introduction
00:22 CHPT3 speed
01:25 Drivetrain / Chain
02:12 Drivetrain / Derailleur
03:02 Drivetrain / Internal Hub
04:28 Rolling Resistance
07:01 Speed Difference (Casual Riders)
07:58 Aerodynamics
09:02 Speed Difference (Performance Riders)
09:42 Take Away

References:
https://www.bicyclerollingresistance.com/
https://www.gribble.org/cycling/power_v_speed.html [Cycling Power]
http://www.ihpva.org/HParchive/PDF/hp50-2000.pdf
http://www.ihpva.org/HParchive/PDF/hp52-2001.pdf
Bicycling Science, Fourth Edition, D.G Wilson, MIT Press, 2020

#Brompton #2bikes4adventure

Copyrights
- Music: The Day is Close - The 126ers
- Derailleur Bicycle Drivetrain CC BY-SA 3.0 Wikipedia, Keithonearth