Thoughts on 'Air-Free' tires?

[1800vtx]

It almost goes without saying, you upgrade your bike to go electric, you should probably upgrade your tires as well.

I've noticed quite a few suggestions for tires that have steel beads, tougher or thicker tread, so that they can withstand the abuse that you'll throw at them compared to a 'regular' bike.

What I haven't seen is any mention of 'air-free' tires. Normally these aren't to popular with the regular biking crowd due to their additional weight, but I would think that because there is no tube/tire to pop or leak, their added durability, plus its added benefit of getting a really high psi rating (think 175psi), that these tires would be a natural choice for ebike converts.

Any thoughts?

 

[tron]

I would question the high speed stability since you almost always go faster on an e-bike. Most "foam" tires are for low speed applications. You would probably be better off with good high pressure tires and self sealing tubes or "slime" inside your tires.

http://www.airfreetires.com/

http://www.bikeforums.net/archive/index.php/t-654.html

Urethane has replaced rubber on millions of vehicles. Issues of heat build up prevent urethane from being used in high speed applications. Many scooters have solid tires though.

Since the cubic volume of urethane needed to make the same size tire as one that is air inflated, the cost of the urethane tire will always be more. This limits where the tire can be used at the OEM level because the OEMs aren't about to raise the cost of materials needed to make a product regardless of percieved benifit. Congressional action is usually needed before the OEM will entertain using more expensive componentry.

Again, the bicycle tire makers do not engage in real R&D to the extent that the motorcycle or car tire makers engage in. If there was true R&D, then the $40.00 bike tire would cost $80.00. But wait, just how is it that I can buy either a car tire with a 40,000 mile warranty and a bike tire with no warranty both for $40.00? You know why? Because they found out that you will pay $40.00 for a bike tire, not because it is worth it. Economy of scale doesn't work here because more bike tires are made in the world than car tires.

You are getting ripped off by foreign multinational companies and you are convinced there is no such thing as a substitute. This is a recipe to ensure that innovation comes slowly and that prices will only rise.

A rubber bike tire that lasts longer will only cause the tire maker to sell fewer product in the long run. Sure he could get a bump in market share, but that would quickly erode once his competition comes out with the exact same thing. Rubber bike tire production would decrease as everybodies product lasted longer. The only way to offset the reduction in production is to raise the cost.

So what if a urethane tire may not be as good as what you use. Big whooppee deal! Does that invalidate the airless tire completely for use by others simply because it isn't good enough for you? You people need to quit making equipment choices for others. Your disdain for tire innovation is evident and totally biased threads in this discussion board only point out just how little many people actually know.

 

[amberwolf]

There are at least two types of these.

The first is a "tube" that goes into your regular tire, but is a "solid" foam ring, already made with a "virtual" air pressure, usually available in several gradations from 30psi (maybe even less) up to at least 50psi.

The second is an entire solid foam tire, tread and all; also likely available in the same pressures.

The main issue I have seen reported with both types of tires is the rolling resistance is significantly greater than with a regular pneumatic tire, though I suspect most people reporting that have the lower "pressure" versions.

A secondary issue that's not important to some riders is that there is not going to be the same shock absorption with a non-pneumatic tire, since the air cells in the foam can't as easily and quickly transmit the energy of an impact or bump from one cell to the next as open air could inside an inflated tube/tire, which will easily compress momentarily near the area of impact and push throughout the rest of the tire.

A third issue that is probably very rare that I'm going to guess is easier to cause on the first type is the entire tire/tube rolling off the rim during a sudden hard turn at speed, where the tire is normally scrubbed along it's rolling axis across the road surface with little problem. An underinflated regular tire could do the same thing, but a properly inflated one should not. Since the foam version must be large enough and/or stretch easily to get it onto the rim in it's "already inflated" state, it can't hold the bead of the tire against the rim with as much force as a pneumatic tire would, so side-loading like that has more of a chance to roll it off the rim.

I have a very old set of 700c or 27" (can't read the tire sidewall well enough) ten-speed tires that have foam tubes in them, and even though they are age-hardened they still feel far too soft to me. They're too old and hard for me to get the tire off the rim so I can't see if they have a marking for their brand, model, or "pressure", so I'm not sure if it's because of age or the original design. (They came off a junked bike I received, so I don't know even *how* old they are).

I once thought that I wanted airless tires, but since I started using Slime brand protector strips plus the chunky "tubeless" version of the Slime leak-stopper, well over a year and a half ago, maybe even two years, I have not had a puncture flat of any kind on the protected tires. (they won't stop rim pinch flats, due to placement up on the sidewall area, or punctures from spoke heads and rim defects, for the same reason, but they're great for any kind of tread/lower sidewall puncture). I also have used the thorn-resistant thicker tubes, which can help too, but I think the strips are the biggest thing that has saved my tubes.

I've had all sorts of things stuck in them, and only ONCE did a roofing nail go thru it, and it was a veritable minefield of nails falling off the back of a truck in front of me, with traffic all around and nowhere else for me to go. I must've hit several of them, but only one made it thru, and it was in exactly the dead center on the rear tire, with my cargo baskets on either side, so the extra weight (which included heavy SLA batteries for a motor test and such) probably helped. But Slime replaced not only the defective strip under their warranty (actually a pair was sent), they also sent me two new thorn resistant pre-slimed tubes! Since then nothing has gotten thru, so it could have been a bad batch, or it could have been Murphy helping guide that nail to the weakspot in the system.

 

[morph999]

some guy on here bought air-free tires for his bike and absolutely hated them. He said it would wobble really bad at any speed over 20 mph.

 

[morph999]

It almost goes without saying, you upgrade your bike to go electric, you should probably upgrade your tires as well.

I've noticed quite a few suggestions for tires that have steel beads, tougher or thicker tread, so that they can withstand the abuse that you'll throw at them compared to a 'regular' bike.

What I haven't seen is any mention of 'air-free' tires. Normally these aren't to popular with the regular biking crowd due to their additional weight, but I would think that because there is no tube/tire to pop or leak, their added durability, plus its added benefit of getting a really high psi rating (think 175psi), that these tires would be a natural choice for ebike converts.

Any thoughts?

saw your blog. I have a 5303 too but I haven't installed it yet. Mine is on a 26" rim. I also have the same controller as you. That bike is going to be a lot of fun. You'll blow by all the gas-powered scooters.

 

[Drunkskunk]

Quoted from his website: http://www.sheldonbrown.com/tires.html
Airless Tires

Airless tires have been obsolete for over a century, but crackpot "inventors" keep trying to bring them back. They are heavy, slow and give a harsh ride. They are also likely to cause wheel damage, due to their poor cushioning ability. A pneumatic tire uses all of the air in the whole tube as a shock absorber, while foam-type "airless" tires/tubes only use the air in the immediate area of impact.

Airless tire schemes have also been used by con artists to gull unsuspecting investors. My advice is to avoid this long-obsolete system.

They are Junk. The only advantage is flat prevention, but a good set of kevlar tires and liners will nearly eliminate flats, unless you like riding on beds of nails and in holding tanks full of broken bottles. And the argument that solid urethane makes a good tire is based on Junk Science and missrepresentation of the facts.

Urethane has replaced rubber on millions of vehicles. Issues of heat build up prevent urethane from being used in high speed applications. Many scooters have solid tires though.

Sure. Its replaced the BUMPERS of most cars. many Solid rubber suspension parts are made of urethane now, and some formaly rubber seals are now urethane. Notice they didn't say it had replaced Air filled rubber tires. In their argument for the use of urethane, then never show any advantage by example, except to try to make some refrence to scooter wheels. From an engineering standpoint, they might as well have been sugesting solid Iron bike tires, since ball bearings use solid steel balls. Just because its round and rolls, doesn't mean it's suitable for comparison. Dung beatles can be found pushing something thats round and rolls too... the contents of the solid tube vender's statements.

 

[fifthmass]

The first safety bicycle tires (1890's) were solid rubber. They did not work. Pneumatics came along shortly thereafter and the rest is history.

If it were not for pneumatic bicycle tires the Wright brothers would not have invented the airplane.

One day in their Dayton, Ohio bike shop one of the Wright brothers sold an inner tube to a customer. After taking the tube out of the cardboard box it he was absentmindedly twisting the ends on the box in opposite directions while chatting with the customer. He noticed that this twisting caused an opposite warping of the long sides of the box. That gave the Wright brothers the idea for aileron control.

Absolute true history.

Regards,
Bill

 

[www.recumbents.com]

I tested several iterations of airless tires in 2002. (My how time flies)

Long story short, the softer tires ride ok and have good traction but are slow like molasses. The harder tires are faster, but are dangerous to ride on because they are slippery and have no compliance. And they are heavy.

Long story: http://www.recumbents.com/wisil/tires/solid_tires.htm

-Warren.

 

[julesa]

Reid posted an encyclopedic treatment of this topic a while back -- just one of his many contributions to ES:

http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=74

 

[SniperGaulois]

1. Kevlar tyres, i bought some conintental kevlar road/mountain hybrids, and they punctured about 10 times less often than the cheap kenda ones i had in the woods and country paths. lots of manufacturers make kevlar. i also tried tyre goo in the tyres, but it makes repairs pathces much harder because the goo stops them sticking. i now need some 700c kevlar, i think kevlar ROCKS!!!

2. i read someone that did try some non air tyres, he read some good brochures and bought them, but didnt like the feel at all. air really is a wonderful thing to have in tyres.

 

[dogman dan]

I've been shocked and pleased with the quality of the inexpensive Bell brand kevlar tires they sell at wallmart, kmart etc. Very good quality long lasting tread for street use. Out in the dirt, other considerations may apply, with stickier tires having softer compounds that wear out faster.

As for flats, I may have more nails and or huge cactus thorns on my riding routes than anybody. Slime yes, but use double the recomended amount and also use the chunky kind for 4x4's not the smooth kind for bikes. Thicker tubes, yes please also. And liners, I like to make liners out of old unrepairable, extra thick tubes that I have slit along the inner part, removing the valve stem in the process. This way, the liner also protects the tube some where the rim bead is, where a big heavy motor may pinch a hole if you let the air get low and don't notice in time. The best liners I have, in the dirt bike, were made from a worn out set of street slicks. I cut the bead off the tires, and put them inside the tires so I have literally two sets of tires on that bike on one rim.

About once every six months, I pull the tires off the dirt bikes, and using a box cutter, patiently pull all the mesquite thorns out of my tires. Usually it takes at least an hour, to remove the hundreds of thorns. Pulling the tube out of the tire, it sounds like velcro ripping, since at least half of em made it through the tube, past all the liners.

 

[EVnewbie]

I have used various forms of Schwalbe Marathon kevlar belted tires for over 10 years with great results,
My award goes to the Schwalbe Marathon Plus tires though. They have a 5mm thick blue rubber compound under the decent tread before it hits the kevlar belts. I've run over tacks, glass, thorns and other various forms of road hazards without a flat on the Plus tires so they run on the back of both my recumbents and a Marathon Plus ATB 26x2.0 on the back of my son's Norco. They are heavy, they are not fast tires and they are expensive being the downsides. The upsides is they don't flat (in my use) they last for at least 8,000 miles, they grip well in trashy streets to hard packed dirt, have reflective sidewalls and have decent high pressure abilities. The Plus sizes I've used are 32x700C, 20x1.75 and the 26x2.0. The 700C tire has over 3,000 miles on it, the 20x1.75 has 4,500 miles on it and I just purchased the 26x2.0. No flats.
The Marathon Plus ATB 26x2.0 is more a hybrid tire, pumps up to 5 bar (74 PSI) has reflective sidewalls, weighs over a kilo (2.2 pounds) and cost me $45. They are not cheap but I hate fixing flats and my son will damage the rims which are even more expensive. I run Marathons with the kevlar belts on the front to minimize weight and gain some speed.
The Marathons/Marathon Plus series has been used in N. Texas, Turkey, Tampa FL and now Kansas. Tampa was the biggest contributor to flats as my wife proved that a Marathon can be flatted but the Plus held up. Glass and nails were the enemy there.
Anyone else runs the Marathon Plus tires?

 

[John in CR]

2 Words Motorcycle Tires. Other than the junk stuff, bike stuff is ridiculously priced and has no testing standards. Stronger tires, stronger rims, stronger spokes, all cheaper and all work to advantage on our heavier and faster e-bikes.

John

 

[dogman dan]

For my fuji dirtbike, a motorcycle tire would be great on the rear rim with the x5. But do they fit a regular 24" rim? Wouldn't they be likely to rub the frame? or the rim brake calipers? I don't think that bike would fit much bigger than a 2.2 inch wide tire, but of course a surly pugsley would. I'd love one, but it's a lotta money compared to 20 bucks at the flea market for the fuji.

 

[John in CR]

For my fuji dirtbike, a motorcycle tire would be great on the rear rim with the x5. But do they fit a regular 24" rim? Wouldn't they be likely to rub the frame? or the rim brake calipers? I don't think that bike would fit much bigger than a 2.2 inch wide tire, but of course a surly pugsley would. I'd love one, but it's a lotta money compared to 20 bucks at the flea market for the fuji.

They are quoted differently, so you'd probably need a new rim too. They're like car tires and go by rim diameter. For closer to bike-like you'd probably look for the narrowest largest diameter moped or small motorcycle rims and tires. My hub motors were meant for e-moto's, and came with rims and thickass spokes...10 months and not a loose one year. I have 2 sizes, the 14" rim ends up as a 20" diameter tire, but I'm using a pretty fat tire. I also have 17" rims and those end up a 24" diameter wheel. One I haven't mounted yet is a narrow AL 16" rim and a 2ply 2.25" Pirelli tire that is rated for 100mph. It's lower profile than my others and end's up about a 21" wheel, and could definitely handle a rim brake.

John

 

[WonderProfessor]

I absolutely hate flats. So I bought a 700c tire from airfreetires.com to replace the back tire on my Gold Rush. I am convinced that airfreetires.com is just a front for dentists. After a few 40-mile (64-kilometer) two-way commutes, I was ready to see my dentist to see how many of my teeth were chipped and cracked beyond repair. If anything, it was an eye-opening experience -- this is what the folks in the 19th century were subject to on their ordinary and safety bicycles. Interestingly enough, it was a dentist, Monsieur Dunlop, who invested pneumatic tires originally for bicycles. I wonder if he knew he was going to reduce his income from his dental practice ...

Oh, by the way, if anyone wants to purchase a barely used 700c airfreetires.com 120-pound air free tire, complete with rim, just send me a PM.

 

[northernmike]

I'm running glue-on, sew-up tubulars on my daily (non-electric) driver. She's 46 years old and sees 100kms + a week. Love it!

 

[dogman dan]

Ok, that helps John. I knew some were using a moped tire, but didn't know how the sizes worked. It might not matter, I'm getting stronger, and with the weather cooling, I'll be pedaling more on the dirt trails anyway. I just got a used MTB with serious suspension so the hardtail is looking pretty lame suddenly. I might motorize it later, but right now it feels so good to be so light.