If the pedal crank arm length of a bicycle increases....

Click For Summary
SUMMARY

The discussion centers on the impact of crank arm length on bicycle performance, specifically torque and pedaling efficiency. A longer crank arm, such as 180mm compared to 170mm, generates more torque due to the increased perpendicular distance from the pivot point, allowing for potentially easier pedaling under the same force. However, shorter cranks may enable higher RPMs and a more efficient gear ratio, leading to faster speeds despite requiring more force. Ultimately, the optimal crank length varies based on individual rider geometry and performance goals.

PREREQUISITES
  • Understanding of torque and its calculation (Torque = Force x Perpendicular Distance)
  • Knowledge of bicycle mechanics, including crankset and gear ratios
  • Familiarity with power output measurements in cycling (watts)
  • Basic physics concepts, including force and energy
NEXT STEPS
  • Research the effects of crank length on cycling performance and biomechanics
  • Explore the relationship between gear ratios and pedaling efficiency
  • Learn about power meters and how they measure cycling performance
  • Investigate the impact of rider geometry on optimal crank length selection
USEFUL FOR

Cyclists, bike fitters, and sports scientists interested in optimizing bicycle performance through mechanical adjustments and understanding the physics of cycling dynamics.

  • #31
jdavis417 said:
Physics is about "moments", right?
At every given moment, the longer crankarm will produce more torque with a lower force input.
A little physics humor? :smile:
 
Physics news on Phys.org
  • #32
berkeman said:
A little physics humor? :smile:
I DID intend humor, although, upon re-reading it seems kinda harsh. Sorry 'bout that! ;)
 
  • Like
Likes   Reactions: berkeman

Similar threads

Undergrad Why do bicycle gears make pedaling easier or harder?
  • · Replies 19 ·
Replies
19
Views
9K
Undergrad How to Calculate Weight on Pedals from Watts?
  • · Replies 15 ·
Replies
15
Views
5K
Graduate Pedal-force for bicycle @ 43.2mph ?
  • · Replies 7 ·
Replies
7
Views
18K
Undergrad Gear Ratio in Bicycles using Rotational Motion
  • · Replies 63 ·
3
Replies
63
Views
6K
Undergrad Forces Applied to Bicycle Pedals
  • · Replies 6 ·
Replies
6
Views
7K
High School Lever balancing physics (video game design)
  • · Replies 18 ·
Replies
18
Views
3K
Undergrad Bicycle front tire wobble due to weight on the back of the bike
  • · Replies 21 ·
Replies
21
Views
5K
Undergrad Bicycles: Question about Energy Conservation
  • · Replies 9 ·
Replies
9
Views
1K
Undergrad Physics as it Relates to Pedalling a Bike
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Torque and Moment of Inertia of a Lever Arm
  • · Replies 2 ·
Replies
2
Views
3K