Wheel upgrades

[Cruzer]

I am currently using Entry level Easton circuit clinchers and am wondering what the actual BENEFITS are in upgrading other than the obvious weight advantage.

 

I am considdering the Easton 70 carbon SL's for sale in the classifieds, what benefit would I get if I bought them?

 

From a ride point of veiw?

 

From a speed point of view? 

[Bike Mob]

acceleration will be the most marked improvement. Less rotational weight will spin up faster.

 

Also if the wheel is stiffer there will be less energy lost to flex. More road feel will be evident while cornering too.

[Weekend_Warrior]

acceleration will be the most marked improvement. Less rotational weight will spin up faster.

 

 

This is the same as when you have your fly wheel on you car lightened, it help to get the engine revs up faster but i also believe the car loses momentum faster as well, would this be the same in the case of lighter wheels?

[Bike Mob]

We have experimented with lighter wheels with our Racing motorcycles. It's a similar comparison but i think more exteme on the braking side...

 

On a motorbike the braking from speed with lighter wheels was the same at high speed, but as the speed decreased, the lighter wheels stopped progressively faster.

 

They spun up faster as you would expect as well.

 

Compliance over bumps was reduced (feel more bumps) as the wheels react faster to any input.

 

I essence, your wheels will accelrate and decelerate faster than heavier wheels, you will feel more bumps in the road too. They will also be less resistant to changes in direction, so steering actoins will aslo be faster.

[Johan Bornman]

acceleration will be the most marked improvement. Less rotational weight will spin up faster.

 

Also if the wheel is stiffer there will be less energy lost to flex. More road feel will be evident while cornering too.

 

Really? The two of you seem to have done the math. Please let us then have some figures. How much faster will you accellerate with a given weight difference of say 200 grams over the two weels, with this weight taken away entirely from the rim and tyres?

 

How much do you think wheel flex and where do they flex?

 

Describe this different sensation when cornering on the one wheel versus cornering on the other.

 

I'm keen to know.

 

 

[Cruzer]

Thanks!! It seems that they would be a good upgrade. Easton Circuit to 70 SL Carbon's

[Johan Bornman]

We have experimented with lighter wheels with our Racing motorcycles. It's a similar comparison but i think more exteme on the braking side...

 

On a motorbike the braking from speed with lighter wheels was the same at high speed' date=' but as the speed decreased, the lighter wheels stopped progressively faster.

 

They spun up faster as you would expect as well.

 

Compliance over bumps was reduced (feel more bumps) as the wheels react faster to any input.

 

I essence, your wheels will accelrate and decelerate faster than heavier wheels, you will feel more bumps in the road too. They will also be less resistant to changes in direction, so steering actoins will aslo be faster.

[/quote']

 

Am I then correct to summise that braking on a (your) motorbike is not a linear affair? You seem to say that speed reduction is less when the bike is going fast but the decelleration increases as the bike gets slower?

 

Have you any figures to show us? It sounds as if you've somehow plotted this against different wheels of different weights, but using the same brakes all the time.

 

You've apparently done the same type of experiment and gleaned the same data for cornering. Can you tell us how much faster the steering actions were and how weight affected this?

 

Please enlighten us.

 

 

[TNT1]

JB, you know that expression about talking to brick wall? You know by now most of these guys haven't the foggiest notion about wheels, except that more expensive and lighter must make them better riders.... You wont get any answers based on science, and there are clearly people here with money burning big holes....

[Bike Mob]

http://www.analyticcycling.com/WheelsConcept_Page.html

 

I knew that was coming Johan! hehehe

 

I'll try answer your questions:

 

Flex, From my understanding a wheel will flex from the most fixed point Ie the hub, and radiate outwards. The amount will obviously depend on how much side force is applied, from that i can say that sideways force will only make itself evident at the moment of turn and not during midturn. A more flexy wheel should be slower to react as some energy will be lost to forwards motion, inertia. Once your course of motion is stable again they will then be equal.

 

From what I have read - And I am no expert. but the heavier the moving object is, the more resistant it is to change direction.

 

The intial question was will I feel a difference, and the answer is yes.

[Johan Bornman]

JB' date=' you know that expression about talking to brick wall? You know by now most of these guys haven't the foggiest notion about wheels, except that more expensive and lighter must make them better riders.... You wont get any answers based on science, and there are clearly people here with money burning big holes.... [/quote']

 

I know, I know....but lets make them sweat in anyway. It is Friday and I won't be here for two weeks, so I must bank some challenges beforehand.

 

 

[Johan Bornman]

 

 

Flex' date=' From my understanding a wheel will flex from the most fixed point Ie the hub, and radiate outwards. The amount will obviously depend on how much side force is applied, from that i can say that sideways force will only make itself evident at the moment of turn and not during midturn. A more flexy wheel should be slower to react as some energy will be lost to forwards motion, inertia. Once your course of motion is stable again they will then be equal.

 

From what I have read - And I am no expert. but the heavier the moving object is, the more resistant it is to change direction.

 

The intial question was will I feel a difference, and the answer is yes.

[/quote']

 

You haven't been paying attention, have you? The are NO sideways (lateral) forces on a bicycle or motorcycle wheel when turning.

 

You have been reading bicycling magazines, I can tell.

 

 

 

 

[Bike Mob]

 

 

Flex' date=' From my understanding a wheel will flex from the most fixed point Ie the hub, and radiate outwards. The amount will obviously depend on how much side force is applied, from that i can say that sideways force will only make itself evident at the moment of turn and not during midturn. A more flexy wheel should be slower to react as some energy will be lost to forwards motion, inertia. Once your course of motion is stable again they will then be equal.

 

From what I have read - And I am no expert. but the heavier the moving object is, the more resistant it is to change direction.

 

The intial question was will I feel a difference, and the answer is yes.

[/quote']

 

You haven't been paying attention, have you? The are NO sideways (lateral) forces on a bicycle or motorcycle wheel when turning.

 

You have been reading bicycling magazines, I can tell.

 

 

 

 

 

Yes there are...however they are overcome by cornering force during a turn...thus nullifying them.

[Bike Mob]

What I am trying to say might more easily be felt like this:

 

Take a heavy wheel. hold the skewers in your hand and spin the wheel... In a straight line it feels stable...now try turn it.

 

repeat with a light wheel, and observe the difference.

[jabbathemutt007]

 

We have experimented with lighter wheels with our Racing motorcycles. It's a similar comparison but i think more exteme on the braking side...

 

Its not a similar comparison. Motorbike acceleration is several orders of magnitude greater than even this mythical Vernon Koekemoer guy that appears in some peoples signatures could manage on a bicycle. At the low accelerations possible on a bicycle, the mass of the wheel makes no measurable difference to acceleration. Wheel aerodynamics, particularly the front wheel may make some difference although the rider is still the biggest aerodynamic drag on the bike.

 

BTW who the hell is Vernon Koekemoer ?

 

 

 

 

[Bike Mob]

Someone should tell the pro teams they're wasting a lot of money then...

 

Perhaps JB can tell us why they ride lighter wheels?

[Johan Bornman]

Someone should tell the pro teams they're wasting a lot of money then...

 

Perhaps JB can tell us why they ride lighter wheels?

 

I wish you guys would come up with a better retort than "it has to be better because the pros ride it. "

 

This is the tech and science forum, not the marketing forum. Did someone mention a brick wall?

 

They ride lighter wheels because they want to save weight.

 

For the record...once again. Weight savings on a a wheel is just weight savings. Weight on a wheel has the same effect on accelleration as weight on your fat rolls, weight in your water bottle or weight on the padlock and chain wrapped around your seatpost. It has no magical mystical properties no matter what stories the drag racing entusiasts try and import into cycling.