Benefits of Solid Tires for Bicycles: Improved Ride & Reduced Wear

[ice109]

other a bumpy ride and maybe expedient suspension/drivetrain wear, are there any reasons why you would not want solid ( solid rubber, tubeless) tires on a bicycle?

 

[Cyrus]

It would probably be horribly bumpy. That air acts as a damper. You will also have a much larger MOI.

 

[ice109]

It would probably be horribly bumpy. That air acts as a damper. You will also have a much larger MOI.

damn that is absolutely true, and i positively don't want that. i just feel like the compression saps so much energy from me because of inelastic collisions with ... the ground.

 

[Cyrus]

Ride my Carbon fiber bike, and ride my steel frame bike, and you will see the difference in the damping capacity instantly. You do notice the road vibrations that get transmitted through the bike. I would suspect a solid tire would transfer more energy, being one solid piece, than would a tire filled with air that can deform more readily.

Ps, why the sarcasm?

 

[berkeman]

One option for dirtbikes is to run the "bib mousse" foam insert, instead of an inflated innertube:

http://www.motorace.com/miva/merchant.mv?Screen=CTGY&Store_Code=M&Category_Code=MTBM

They are a little heavier, but are commonly used for riding and racing in the rocky desert, like on the Baja races. I don't know if they make versions for bicycles.

BTW, another disadvantage of a solid tire would be the added weight, and the big addition to the wheels' moment of inertia (harder to accelerate).

 

[brewnog]

Aside from comfort, wear and protection, there's the issue of traction too...

 

[ice109]

Ride my Carbon fiber bike, and ride my steel frame bike, and you will see the difference in the damping capacity instantly. You do notice the road vibrations that get transmitted through the bike. I would suspect a solid tire would transfer more energy, being one solid piece, than would a tire filled with air that can deform more readily.

Ps, why the sarcasm?

no sarcasm, i sincerely meant that i positively would not want a bigger MOI.

i don't think you understand what I'm saying, just like an under inflated tire steals energy versus a properly inflated tire i was thinking an inflated tire versus a solid tire steals energy.

Aside from comfort, wear and protection, there's the issue of traction too...

wheels are on a roadbike, don't need traction

 

[Cyrus]

Well, I'm sure it probably does. In an ideal situation you want a solid tire running along a track with cogs on it. Any deformation will result in energy losses, but you made a big assumption when you said comfort aside. You can't put comfort aside on a vehicle with people in it. Even without people, that vibration will tear things appart and cost money. Everything in engineering is a tradeoff.

I like having traction between my road bike and the ground. There's no way you're going to turn without traction. Roads are not banked specifically to road bikes.

 

[ice109]

Well, I'm sure it probably does. In an ideal situation you want a solid tire running along a track with cogs on it. Any deformation will result in energy losses, but you made a big assumption when you said comfort aside. You can't put comfort aside on a vehicle with people in it. Even without people, that vibration will tear things appart and cost money. Everything in engineering is a tradeoff.

I like having traction between my road bike and the ground. There's no way you're going to turn without traction. Roads are not banked specifically to road bikes.

my OP implied i have already considered that the vibration will damage things, that is why i said bumpiness aside; because i already knew that.

i am assuming that the rubber itself will deform to contour the road surface. so therefore i don't need further deformation from the shape of the tire for grip.

a tangential question. how come car tires don't need tube but bike tires do? i do know of tubeless bike tires but you need to glue those to the rim and obviously for cars you don't need to glue anything. so what is the difference?

 

[Cyrus]

I know what your OP implied, but I am pointing out to you the magnitude of your implication in an engineering sense. You are taking the main reason for having non-rigid tires and ignoring it.

How about I ask why airplanes have big wings but ignore the effects of air? Aint going to work.

 

[ice109]

I know what your OP implied, but I am pointing out to you the magnitude of your implication in an engineering sense. You are taking the main reason for having non-rigid tires and ignoring it.

How about I ask why airplanes have big wings but ignore the effects of air? Aint going to work.

duelly noted, do you have any answers to my questions instead of telling me what is unengineerable?

besides you act like there aren't vehicles, with occupants and which were engineered , with solid tires for this exact reason.

 

[Cyrus]

I answered your questions already. See: Cogs.

 

[ice109]

I answered your questions already. See: Cogs.

what do single speeds have to do with anything? or maybe you really do mean cogs plural in which case: what does a cluster/cassette have to do with anything?

 

[Cyrus]

When you have a cog type system on your wheels and on the ground, almost all the energy gets transferred from the axil to moving forward. You don't have to worry about traction or slip. There is very little deformation, and loss of energy, between the gears. That would be the most ideal 'solid' tire.

If you try to make a 'solid' tire without any gears on it, you won't be able to take any turns that don't have a bank built into them.

 

[berkeman]

Well, since I have absolutely no idea what you guys are talking about anymore, I went back and googled "bib mousse" +"bicycle tire", and got some hits. Here is the solid foam bib mousse insert info for Michelin MTB tires.

http://shopping.yahoo.com/s:Cycling:4168-Brand=Michelin:4492-Sales%20&%20Deals=All%20Sale%20Items

Does that help with the OP?

 

[ice109]

When you have a cog type system on your wheels and on the ground, almost all the energy gets transferred from the axil to moving forward. You don't have to worry about traction or slip. There is very little deformation, and loss of energy, between the gears. That would be the most ideal 'solid' tire.

If you try to make a 'solid' tire without any gears on it, you won't be able to take any turns that don't have a bank built into them.

are you seriously saying i should replace my entire wheel with a 27cm cog? and build a road with teeth?

i don't see why you wouldn't be able to make turn on a solid wheel. think rollerblade wheels.

Well, since I have absolutely no idea what you guys are talking about anymore, I went back and googled "bib mousse" +"bicycle tire", and got some hits. Here is the solid foam bib mousse insert info for Michelin MTB tires.

http://shopping.yahoo.com/s:Cycling:4168-Brand=Michelin:4492-Sales%20&%20Deals=All%20Sale%20Items

Does that help with the OP?

although that's interesting, its not for what I am imagining. especially since its not rigid, although obviously more rigid than a tire with no air in it.

 

[Cyrus]

Hmmm, that's a good point. Give me some time to think about that. The solid tire might have grip, but let me double check. I'm having issue seeing how a solid tire would be able to transfer energy to the road. All tires have some finite amount of deformation, and I think this deformation is critical in moving forwards.

 

[ice109]

Hmmm, that's a good point. Give me some time to think about that. The solid tire might have grip, but let me double check. I'm having issue seeing how a solid tire would be able to transfer energy to the road. All tires have some finite amount of deformation, and I think this deformation is critical in moving forwards.

why would it be? all you need is for the ground to apply a force on you. if a wheel is rolling without slipping it is the friction force applying this force. you don't need deformation to have friction.

 

[Cyrus]

But F=u*N at the macroscopic level. When you have a perfectly rigid disk, you will have an infinitely thin line of contact area between the disk and the ground, and possibly F != u*N anymore.

 

[Cyrus]

You can check out this http://hyperphysics.phy-astr.gsu.edu/hbase/frict3.html

 

[ice109]

But F=u*N at the macroscopic level. When you have a perfectly rigid disk, you will have an infinitely thin line of contact area between the disk and the ground, and possibly F != u*N anymore.

yes for a perfectly disk you would need deformation to get a contact patch for friction to do its thing but that deformation still doesn't cause friction.

you don't need "hooks" to cause friction, you need proximity between valence electrons

You can check out this http://hyperphysics.phy-astr.gsu.edu/hbase/frict3.html

that's pretty irrelevant

 

[Cyrus]

I don't understand what you mean by 'cause' friction. I am saying without deformation, I don't think you will be able to produce enough friction to move forwards.

Did you scroll down the link?

 

[ice109]

I don't understand what you mean by 'cause' friction. I am saying without deformation, I don't think you will be able to produce enough friction to move forwards.

Did you scroll down the link?

ahh i misunderstood your first post mentioning deformation. yes i agree for a wheel (read: rigid disk) deformation is critical to movement. but only for a disk

 

[Cyrus]

I got to think about this for a bit, let it stew in my head overnight and let me look online to see if I find anything for an ideal perfectly rigid disk.

 

[ice109]

I got to think about this for a bit, let it stew in my head overnight and let me look online to see if I find anything for an ideal perfectly rigid disk.

you and me both man, solid tires: the new wave in road racing! we're going to rich

 

[Cyrus]

Thats why I brought up Gears. A perfectly rigid gear will transfer energy, because now you are not relying on friction to move you forward.

 

[ray b]

try and ride a junk bike with no tyre on just the rims
lots of sparks but little grip

tube less tyres work on solid wheels [plastic on bikes]
but spokes are hard to seal and let the air excape

 

[BobG]

Deformation of the tire definitely affects its static coefficient of friction. A tire with less air has more traction and will be more effective when accelerating or changing directions. Tire deformation also affects your rolling coefficient of friction. Once up to speed, a tire with less air takes more effort to keep it rolling at the same speed.

On a car, underinflated tires give you better accelertion and cornering, but also decrease your gas mileage.

On a bicycle, the same principle would apply. For a road bike that will primarily travel the same speed in a straight direction for long distances, a rigid tire that resists deformation will make it easier to maintain your speed (even if it will be more uncomfortable as well). It will also require you to go slower around the corners, which also means you'll have to accelerate back up to cruising speed from a slower speed.

It's a trade-off and I don't know which would have the best overall efficiency. I would think that a bicyclist spends a lot more time going straight at a constant speed than cornering or going up hills.

 

[SRode]

Some of these postulate are rediculous, but to answer your question a solid rubber tire would be better because it would weigh more and conserve more angular momentum. This would be ideal if you were on a level surface and were traveling a long distance (same principle as a flywheel). The downside is that it would require a lot more force to slow down, thus wearing your brakes more, and greater force to accelerate. If you were trying to apply this to a car, it would be practical in that it would increase MPG because less engine power was required once in motion, but the stress it would put on the horizonal components in turning would be immense. Also the logistics of shipping pieces of heavy solid rubber like that would not be feaseable.

 

[berkeman]

Some of these postulate are rediculous, but to answer your question a solid rubber tire would be better because it would weigh more and conserve more angular momentum. This would be ideal if you were on a level surface and were traveling a long distance (same principle as a flywheel). The downside is that it would require a lot more force to slow down, thus wearing your brakes more, and greater force to accelerate. If you were trying to apply this to a car, it would be practical in that it would increase MPG because less engine power was required once in motion, but the stress it would put on the horizonal components in turning would be immense. Also the logistics of shipping pieces of heavy solid rubber like that would not be feaseable.

All I can say (trying to be constructive here) is that most of us do not ride/drive on flat land for long periods at constant speed.