Questions tagged [physics]
The physics tag has no usage guidance.
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Do ALL non-instantaneous deceleration events transfer weight to front wheel?
There's a great question and discussion on hub vs disc brakes here. That got me wondering this: do ALL non-instantaneous deceleration events transfer weight to front wheel?
I've got a follow up ...
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When does the braking power stop scaling with Rotor Size
It's commonly established that the braking power scales with rotor size, and an optimal braking technique is to provide enough force for the rear wheel just to lift up. However, my question is wouldn'...
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Why do front gears become harder when the cassette becomes larger but opposite for the rear ones?
I noticed on mine and other road bikes that the "big" front gear becomes "harder" (more distance per revolution) when it switches to the bigger cassette. That makes sense, larger ...
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Infeasibility of a mechanical wind-up spring KERS (Kinetic Energy Recovery System) for bicycles
I'm curious about an explanation for why a wind-up spring KERS (Kinetic Energy Recovery System) isn't worth it for a bicycle.
The system I have in mind is instead of braking the rear wheel you engage ...
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Holding all other things constant, what is the performance difference of adding a pound of weight to each pedal on a bicycle?
I am looking for an answer that may include watts and/or calories per hour only. Please do not discuss wheels, tires, bearings, body weight, frame weight. Just help me understand the physics of adding ...
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storage pulley rack for a diagonal ceiling
i want a system based on a ceiling pulley for a quite heavy bike, the storage room is under the roof, so the ceiling (cement concrete material) is not flat.
Do the ceiling racks work well?
What about ...
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Momentum and gyroscopic difference between wheel sizes
A common folk wisdom in mountain biking is that smaller wheels (like 26") are "quicker" or "more flickable" and "better for courses that require lots of speeding up and ...
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How does biking speed correlate with the required effort?
The simple answer is that the faster you go the more effort/energy it takes but I would like to understand this in more detail, especially at relatively low speeds. Assume a flat smooth road and fix ...
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Would a heavy fork cause problem when climbing?
I have a MTB which has a 1.600g frame and 2.600g suspension fork. Does being heavy at the front cause a disadvantage when climbing?
- 2,090
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Healthiest bike posture for slower long rides
I'm looking for some evidence on bike posture and overall best positioning for healthiest rides that might be "long" (say around 30km) but also where speed is not a concern - think of ...
- 1,015
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How fast can a cyclist accelerate from a standing start?
I'm less interested in the empirical answer to this question and more interested in the theoretical physical dynamics that govern this.
I understand that the rider applies some force to the pedals (...
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Minimum speed when riding rollers
I have a set of rollers and a single-speed road bike. My 80-90 rpm speed is 27-30 kph (17-19 mph). I feel like I would be more stable with higher rpm, but it's harder to sustain.
If I understand this, ...
- 11
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Understanding science of speed difference between two bikes
I have two MTBs and one is slower than the other.
Bike1 has Deore derailleurs and a double chainring with 10 sprockets and Shimano hubs. Which has a great speed irrespective of the gear combination.
...
- 11
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Counter-intuitive steering in crosswinds with hands off the bars
It should not be surprising that it is difficult to ride in a straight line with both hands off the handlebars when there is a crosswind.
However, I find it most unintuitive, that for example if ...
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CdA of a bike without rider
This question at aviation.se got me calculating the acceleration of a bike strapped to the outside of a plane if the straps broke. As you do. I couldn't find a figure for CdA of a bike without rider ...
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