Spinning round objects

freddiegrubb

Lets say the dirty word--- WHEELS--- now we've all read the oohs & aaghs about weight of the new wheelset, but nobody seems to mention "the flywheel effect", heavier wheels may take slightly longer to spin up to speed but surely the kinetic energy that's stored removes the lightness factor. Interesting opinions sought, especially Mr. uggo. I've seen some mighty marine flywheels in my time & nobody waxed lyrical about their lightness.

declan1

Heavier wheels are better for flat and downhill riding, due to the increased momentum and stability they offer. A great deal of riding is not perfectly flat or downhill. This is where low weight helps. Low weight equals better acceleration for the same effort, and climbing is basically constant acceleration.

MattC59

declan1 wrote:

Heavier wheels are better for flat and downhill riding, due to the increased momentum and stability they offer. A great deal of riding is not perfectly flat or downhill. This is where low weight helps. Low weight equals better acceleration for the same effort, and climbing is basically constant acceleration.[/quote]


No it's not, unless you're a superb climber and accelerate all the way up the climb, in which case, I'm sure Sir Brailsford would be interested in you !
I assume that you mean that you're not accelerating, therefore your acceleration is zero and your speed is constant.

declan1

MattC59 wrote:

declan1 wrote:

Heavier wheels are better for flat and downhill riding, due to the increased momentum and stability they offer. A great deal of riding is not perfectly flat or downhill. This is where low weight helps. Low weight equals better acceleration for the same effort, and climbing is basically constant acceleration.

No it's not, unless you're a superb climber and accelerate all the way up the climb, in which case, I'm sure Sir Brailsford would be interested in you !
I assume that you mean that you're not accelerating, therefore your acceleration is zero and your speed is constant.

Every pedal stroke you accelerate a little, then you lose speed. You then accelerate again on the other pedal stroke. If you could put down constant power as you said you would have a lot of people after you!

I should have said small bursts of acceleration :P

Wirral_paul

declan1 wrote:

MattC59 wrote:

declan1 wrote:

Heavier wheels are better for flat and downhill riding, due to the increased momentum and stability they offer. A great deal of riding is not perfectly flat or downhill. This is where low weight helps. Low weight equals better acceleration for the same effort, and climbing is basically constant acceleration.

No it's not, unless you're a superb climber and accelerate all the way up the climb, in which case, I'm sure Sir Brailsford would be interested in you !
I assume that you mean that you're not accelerating, therefore your acceleration is zero and your speed is constant.

Every pedal stroke you accelerate a little, then you lose speed. You then accelerate again on the other pedal stroke. If you could put down constant power as you said you would have a lot of people after you!

I should have said small bursts of acceleration :P

.... and an equally short burst of deceleration

freddiegrubb

Comments above- does this mean I can expect to start walking earlier on hardknott & wrynose?

declan1

freddiegrubb wrote:

Comments above- does this mean I can expect to start walking earlier on hardknott & wrynose?

Lighter wheels mean you can start walking later on hills

freddiegrubb

No no no, I can't climb never could & I've just put new tyres on (more rubber ) this is what started the train of thought about wheel weight. C"mon Mr. uggo I would like to read your take on the issue (seriously)

capt_slog

MattC59 wrote:

declan1 wrote:

Heavier wheels are better for flat and downhill riding, due to the increased momentum and stability they offer. A great deal of riding is not perfectly flat or downhill. This is where low weight helps. Low weight equals better acceleration for the same effort, and climbing is basically constant acceleration.[/quote]


No it's not, unless you're a superb climber and accelerate all the way up the climb, in which case, I'm sure Sir Brailsford would be interested in you !
I assume that you mean that you're not accelerating, therefore your acceleration is zero and your speed is constant.

I think he's correct. because....

If you are facing downhill and let off the brakes, you will start to roll. You will go faster and faster as obviously you are accelerating due to gravity. To maintain a constant speed, you would have to apply a braking force to combat the acceleration due to gravity, hence you are under constant deceleration.

Going uphill, the opposite has to be true. To maintain a constant speed, you have to apply a constant acceleration to combat the acceleration due to gravity which is trying to make you stop. Certainly if you are accelerating faster than the component of gravity pulling you back, then you will get faster and faster going uphill, and Sir Brailsford could be your mate.

keef66

Capt Slog wrote:

I think he's correct. because....

If you are facing downhill and let off the brakes, you will start to roll. You will go faster and faster as obviously you are accelerating due to gravity. To maintain a constant speed, you would have to apply a braking force to combat the acceleration due to gravity, hence you are under constant deceleration.

Going uphill, the opposite has to be true. To maintain a constant speed, you have to apply a constant acceleration to combat the acceleration due to gravity which is trying to make you stop. Certainly if you are accelerating faster than the component of gravity pulling you back, then you will get faster and faster going uphill, and Sir Brailsford could be your mate.

I'd concentrate on the philosophy and give up entirely on the physics if I were you...

rolf_f

declan1 wrote:

freddiegrubb wrote:

Comments above- does this mean I can expect to start walking earlier on hardknott & wrynose?

Lighter wheels mean you can start walking later on hills

In other words, lighter wheels prolong the agony. So get some Cosmic Carbones!