# Airless bicycle tires



## jtr1962 (Feb 22, 2005)

I read a post here a while back about airless bicycle tires. I think a company called Zeus makes them. It seems like I'm constantly getting flats thanks to all the morons who throw tacks and beer and malt liquor bottles in the street. 90% of the time it's the rear wheel which gets the flat. Since it's such a pain in the neck to take the rear wheel off I usually get disgusted and let the bike sit a week or more before trying to fix it. Needless to say, this is seriously cutting into my fitness regimen. I still walk a few miles a day but it isn't enough. Anyway, has anyone tried the airless tires? What are the downsides? I've had my fill of flats so unless there are serious drawbacks I would like to go with airless tires. BTW, I've tried Kevlar tires already. They didn't seem to make much if any difference.


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## Leow (Feb 22, 2005)

Airless tyres are not as comfortable or as efficient to ride.
They would be good for regular short journeys but not so good for longer ones.

For longer journeys I'd insert a breaker strip
e.g. "Slime Tire Liners"
http://www.nashbar.com/profile.cfm?sku=1886&siteid=pjv1c.QzcE0-xfu4wBFxonQ5LmlSgXwlkg

In a regular tyre the entire volume of air acts as an "air-spring".
In a solid tyre only the air in the foam rubber at the point of contact with the ground acts as a spring.

Hope this helps,

LeoW


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## gregw (Feb 22, 2005)

Did a search on Google and found GreenTyre. They seem to have a pretty wide variety for bicycles as well. See the list here. They even have a 30 day trial period, so you can always buy a set to try out for a few weeks and return it if they don't feel right.


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## dukeleto (Feb 22, 2005)

I can second the recommendation for tire liners; I haven't punctured once in town since I installed some over a year ago. 
Before that, I used to pucnture around once every 2 months

Olivier


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## Al_Havemann (Feb 22, 2005)

Here’s one thing worth trying, especially if it's a road bike. Remove the tires, spread it open on a workbench (two people are best for this) wipe the inside of the tire down first real good with alcohol to clean them, let dry then run a strip of 1" wide, good quality friction tape all around the inside of the tire. You might want to use a wider tape for mountain tires. Dust a little talc into the inside and reinstall. 

Believe it or not this works just about as well as the expensive and heavy tire liners sold at shops and weighs practically nothing. Just this simple fix probably stops 90% of the flats I used to get. It’s been over three years (and two sets of tires) since I’ve had one.

Al


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## Lurker (Feb 22, 2005)

I agree with the tire liner suggestion. Also, make sure you are starting with sound equipment such as a new inner tube, tire with sufficient tread (preferably new), and a wheel that is in good condition and has no protrusions inside such as spoke ends, etc. I like to put a wheel liner in as well. This is just a strip of plastic that separates the inner tube from the spoke nipples. Then when you install everything, put talcum powder in there to prevent any chafing between the tube and tire. 

I used to be a serious cyclist, both on a road bike with narrow slick tires and on a mountain bike riding in thorny country. I have had many flats, but rode for years without a single flat once I set my tires up that way.

This sounds like a lot of trouble and expense, but really that stuff is pretty cheap and installing it is not much more trouble than doing a basic flat tire repair. The pay-off is that you do it once and ride trouble-free from then on. The thing that kills me is I see people repairing a flat tire and they try to patch an old inner tube instead of spending a few bucks on a new one. Invariably the tube gives them more trouble pretty quickly and the few dollars they saved means tearing the wheel apart once again. Penny wise and pound foolish. Same thing re-using worn out tires. Do it right the first time and be done with it.

And one other tip, always keep a spare fresh inner tube on hand. At least then the repair does not require a trip to the store and you are never tempted to patch.


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## IlluminatingBikr (Feb 22, 2005)

They also make extra thick tires, that are less likely to puncture. My dad has one for his rear tire; I believe it's called an armadillo. You can also get more puncture resistant tubes, which is what I have on my bike. IIRC, the bike shop didn't recommend using both at the same time, but one or the other is fine.


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## Sub_Umbra (Feb 22, 2005)

The Kevlar in a Kevlar bike tire is only in the *bead*, (the part that locks the tire ti the rim), so it won't make the tire more flat resistant.

The airless tires I've ridden on had two problems: they were bumpy -- lots of vibration. Also, many are made of polypropelene. Polypro has a melting temp of only ~300F so if you lock up the brakes and skid on it you may melt a flat spot on the tire that will never go away.

Here are four things that prevent flats:

1..Mr Tuffy strips.
2..Thorn-resistant tubes. (much thicker than stock)
3..Slime in the tubes.
4..Cloth rim tape. (prevents damage to the tube from the rim)

I use all, all the time except the cloth rim tape. 

Be advised that all of the first three will make your bike *heavier* and the Slime will cause an increase in *'rotational inertia.'* (Airless tires should add *even more* weight and rotational inertia than the above methods.) I actually use 2-3 times the recommended ammount of Slime. As part of the reason I ride is the exercise, I don't care about the weight.

I moved to these steps one at a time to prevent the constant flats I was having and I got to the point where, as I said, I *always* use the first three. These three things have cut my flats by at least 95%.

Start with number 1 and keep adding things until your flats become manageable.


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## cheesehead (Feb 22, 2005)

There are tires with Kevlar lining the tire, these worked very well for me. When I got home I'd just pick the glass out of the tire, but never got a flat. 

If it's a mountain bike, you can install 2 tubes and if one goes flat, you'll still have the other to get you home. I've never tried this, just read about it. Seems like a lot of messing around to me. The kevlar lining strips seem easier (or Kevlar lined tires, if you find them).


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## jtr1962 (Feb 22, 2005)

Thanks guys for the all the ideas so far. It looks like I have lots of alternatives even if the airless tires don't work out.

To answer a few questions regarding my usage, I typically ride 20 miles or less per day. I never take the bike on extended trips nor do I plan to. The furthest I'll get from home is maybe 15 miles so comfort considerations on long journeys don't concern me. My bike is a road bike with skinny high-pressure tires which I usually overinflate for less rolling resistance and more stiffness so my ride comfort is none too great even with air tires. Combining that with NYC's potholed streets and my riding style only makes it worse. Basically, I ride the way MTA bus drivers drive-I continue to accelerate regardless of street condition until an obstacle or red light forces me to slow down or stop. 30+ mph on heavily potholed streets is not unusual for me. If I slowed for every bump I'd never make good time or get a decent work out. Point of fact, I can't have my tire pressure too low or I might "bottom out" the tire and bend a rim on a particularly nasty bump. This is my main concern with switching to airless tires, which I do plan to try soon. The one on I'm considering on that site gregw linked to has an equivalent pressure of 95 psi. This should be fine for rolling resitance but will the tire give more than an air tire at 95 psi would over, for example, a pothole? I don't want to end up with badly dented rims in short order and I've heard people complain that some airless tires feel like they're riding on flats.

The melting point problem mentioned by Sub_Umbra is a minor concern for now. I adjust my rear brake so it can't lock the wheel, and I usually use my front because it has greater stopping power. In other words, I can't remember the last time I slid a tire. Traction is most definitely a concern though. Are these airless tires equal to rubber in that area? I _can_ adjust my riding style if they're slightly worse (i.e. just take corners slower).

I'll try the tape suggestion when I repair my flat rear tire. Would duct tape work also? As for the other ideas, I've been using powder and cloth rim tape for years. I've never tried a thorn resistant inner tube. I think the problem was that most I've seen are only made to fit mountain bike tires or I would have already tried them. If the airless tires don't work out I'll give them a try. I'd still be really amazed though if all these things reduced my flats by 90 to 95% as some here claim. The amount of road debris around here is enough to drive any cyclist crazy. I've ended up with three inch nails in my tires, for example. The worst flats though are the slow leaks where the bike is fine when you put it away but not the next day. I can find and fix a big leak without taking the wheel completely off but not a slow one.

Any thoughts on taping down a piece of thin (maybe 0.005") sheet steel inside the tire? Has anyone actually tried something like this? If the airless tires turn out to be a bad product I might very well do this out of desperation.

Any airless inner tubes out there? That might be the best of both worlds if they can simulate a pressurized tube well.


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## Lurker (Feb 22, 2005)

30+ mph on heavily potholed streets on skinny, overinflated tires. That's your problem right there. You are exceeding the design limitations of the tires. Any chance of switching up to a tire that is fatter and more rugged? I thought a lot of NYC messengers switched to mountain bikes for that reason. You don't have to go that far, but a change in tire size would help.


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## PANZERWOLF (Feb 22, 2005)

tire liners are a cheap and good solution, since i use them, i have about 1 flat a year (was about 1/month w/o them) and then it's probably my fault (like jumping right onto a concrete edge instead of over it)


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## jtr1962 (Feb 22, 2005)

So you're saying that going too fast on bumpy roads can make the tires more prone to getting flats? I had actually considered that possibility. It seems I'm more likely to get flats whenever I rid really aggressively. I always assumed it was because I had less time to avoid road debris rather than because I was overstressing the tires. I suppose I could put 700x35 on my rims and/or slow down occasionally. BTW, I don't always go 30+ mph on potholed streets but I sometimes let my "lead feet" get the better of me and it does happen. My usual cruising range is 21 to 25 mph. Sometimes the road will be smooth, I'll increase my speed, and then a bumpy section sneaks up on me. The real answer here of course lies with NYC DOT but as anyone who lives here knows hell will freeze over before we have smooth roads.


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## Sub_Umbra (Feb 22, 2005)

I forgot to mention that when I used to ride a lot more I would carefully look over both tires every week for tiny pieces of broken glass and pick them out. If not removed some of them will eventually work their way all the way through whatever you put between them and your air. It saves lots of trouble to just flick them out with the point of a knife.

There is Murphy's law to contend with, also, no matter what you do. Once I picked up a nail through the sidewall that was so huge it dumped the air, the slime and even stopped the back wheel from turning. Geeze...

There *are* thorn resistant tubes smaller than mountain bikes use, but I don't know if they exist in the hidiously small 'suicide' sizes.


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## BentHeadTX (Feb 22, 2005)

I used to have flats... the last one was April 2004 and before that, September 1999. That looooooong stretch of time consisted of using kelvar BELTED tires (not kevlar beads) thorn resistant tubes for a year of that (in Korea) and I don't use racing tires. 

Presently, I use a 20x1.50 (406x40) Schwalbe Marathon 100 PSI and 700Cx35 (622x37) Schwalbe Marathon Slick 87 PSI on my recumbent. My wife has been running Marathons on her recumbent for 1.5 years and has never had a flat. 

While riding across Oklahoma on a week-long group ride, I heard a loud pop and crunching sound. A goat-head thorn punched into the tire, hit the belts and was crushed...no flat! 

If you really don't want any flats, Schwalbe makes this monster of a tire called the Marathon Extra or something along those lines. It has a very, very thick soft stuff under the treads and it is pictured with tacks stuck in the tire. /ubbthreads/images/graemlins/faint.gif They are heavy but it takes a nail gun to get flats from what I see. 

I had a friend that put "air-free" things on his recumbent (he weighed 275 at the time) The problem with those things besides weight, bone-rattling ride and poor traction was they trashed his rims! When those things get hit by a pot hole, they transfer the force directly to the rim instead of cushioning the blow. After he replaced his rear wheel, he went to kevlar tires and flats rarely. 

My battle wagon setup for Korea was rather insane. I used a Specialized Nimbus Armadillo (kevlar belts)35x700C and thorn resistant thick inner tubes for the rear. On the front, a Snafu Rim Job (that is the name...gotta love Freestyle names) that tire was 130 PSI 20x1.95 with kevlar belts. That combo handled riding in over 500 meters of glass. I was wondering why the dirt road had a greenish sheen and rounded a corner--straight to mountains of crushed glass at a recycling center! I picked up my recumbent, brushed the tires off and carried it away. No flats ever with that combination. 

I had one flat in the last 5.5 years, a construction tack punched through my back tire so what are you going to do? My first year of riding my recumbent, my rear 700Cx28 kevlar belted tire flatted 3 times. My front Schwalbe City Marathon 20x1.25 115 PSI tire had kevlar belts also, ran it for 1.5 years without a flat. 

To make this loooooooong post clear, run slightly wider kevlar belted tires and if need be, thorn-proof inner tubes. I have had great luck with Specialized Armadillo and Schwalbe Marathon series of tires. The 700Cx28 was an IRC so I avoid those.


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## Leow (Feb 23, 2005)

[ QUOTE ]
*jtr1962 said:*
BTW, I've tried Kevlar tires already. They didn't seem to make much if any difference. 

[/ QUOTE ]

I'd recommend Panaracer Pasela Tourguard 28mm (actually 25mm) for chucking a road bike fast round pot-holed streets.

I use them through town and around rough country lanes with plenty of debris and occasionaly thorn cuttings.

I only start getting punctures when eventually the rubber tread starts wearing off the carcass.

Again as other's have said a solid tyre would probably kill your rim over potholes.
LeoW


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## jtr1962 (Jul 31, 2007)

I'm bumping this thread because I've starting riding a lot more lately, so I plan to give my bike a major overhaul within a month or so. First, I'll definitely be getting new wheels. I'm considering these. My main concern is that these only have 24 spokes compared to the 36 spokes I've used all my life. Is my concern warranted, or has wheel/spoke technology advanced to the point where a 24-spoke wheel can handle rough city riding? On the plus side, the 24 aero spokes instead of 36 round ones in front, plus the aero profile, should help. I plan to use my rear disc wheel cover in back as I'm doing now, so no real advantages there other than maybe lighter weight. 

As for tires, I'd still like to go airless. Have any major advances happened in the intervening two years since this thread was started? Reading up on airless tires it seems like the major disadvantage for me would be higher rolling resistance, on the order of 0.015 Crr compared to perhaps 0.005 to 0.006 for a decent air tire, at least according to tests run about 2 years ago. Has this been overcome, or at least mitigated to the point where the difference in Crr is only 0.001 to 0.003 instead of 0.01? I don't want anything which will make my bike noticeably slower. A few tenths of a mph won't bother me, but I couldn't live with it being 3 or 4 mph slower for a given power input.

I'm also probably going with a 10-speed Shimano cluster (probably 11-23) in back. I know I'll need a 10-speed chain and a new rear derailleur (I need one anyway since the old one is barely functional). Now will I also need a new front derailleur and chainrings? It seems there are mixed answers on this question on bike forums.

I guess this is taking the thread a little OT but I figure this is preferable to starting another one with some of the same questions.


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## Trashman (Jul 31, 2007)

Slimed tubes have worked great for me. I've sprung as many as 20 leaks on a single tube (no, not at the same time!) and the slime sealed up the leak every time. At Walmart, I've seen heavy duty (thorn resistant) tubes with slime already in them (as well as regular pre-slimed tubes), but none for skinny tires. Slime should really help a lot, though. I know what you mean by having a flat cut into your workout routine. My bike tires have been flat for a couple of years now and this whole time I've been meaning to go out and buy some pre-slimed heavy duty tires! Honestly, I've literally been thinking, regularly, about buying them! I going to buy them tomorrow....tomorrow....tomorrow.......(remember that commercial for ITT technical institute?)


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## koala (Jul 31, 2007)

They are fine, in fact 24 spokes has been out for quite sometime. Also for MTB.

Try these Shimano WH-7801-SL




front/rear 16/20 spokes. They are very tough and race proven. 7801-SL is not only 16/20 there are other models as well. Other choice is Mavic 18/20 wheels, very very solid. The wheels themselves are work of art. I can stare at them for the whole day. Less spoke = less rotational weight = less drag.



jtr1962 said:


> First, I'll definitely be getting new wheels. I'm considering these. My main concern is that these only have 24 spokes compared to the 36 spokes I've used all my life. Is my concern warranted, or has wheel/spoke technology advanced to the point where a 24-spoke wheel can handle rough city riding? On the plus side, the 24 aero spokes instead of 36 round ones in front, plus the aero profile, should help. I plan to use my rear disc wheel cover in back as I'm doing now, so no real advantages there other than maybe lighter weight.


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## greenlight (Jul 31, 2007)

This thread brings me back to about 1980, when I bout some 'no-more-flats' solid foam tire inserts for my BMX bike. They do work, and the kids don't really notice the extra jarring.

That bike was stolen from the garage, and I was upsed over it for a while. It was pretty nice, some kid is probably still riding it, and wondering how the tires stay so full.


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## Led_Blind (Jul 31, 2007)

Good thread. 

I ride a mtn bike to work 3 days a week as well as a crap load of bush riding. My main issue were pinch flats and less often ther would be a thorn in the tyre wall\bed. The bike runs tubeless tyres and now both the frot and back have tubes. 

To get around all the flats we removed the tyre, cut a strip of tough cotton type material to fit inside and painted it in there with a thin silicone mix. The tubes have been removed, tubless valves installed and over 6 months of riding without a single flat. 

On the negatives, the tyres are now heavier and you notice that in the bush when bouncing about of loggs and rocks. The bike is harder to flick around, but meh, its better than flats and when the bike has an unladen weight of 14kg i am not too fussed.


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## Dr Jekell (Jul 31, 2007)

I run a road bike with front suspension and large knobly tires for going to work, into town etc

When I inflate the tires I usualy slightly underinflate them (Max 65 PSI normaly inflated to 60 PSI) and havn't had a puncture in the 3 years of having the bike using it at least 10 - 20 times a week.

I have (unfortunatly) riden over a lot of broken glass and other pointy things that people like to leave lying around and have had no problems except when you get that sinking feeling when you hear glass going crack.

When you run tires at or above their stated max presure rating you are reducing the amount of space inside the tire that the tube can expand into when going over bumps, obsticals and the like. Also the tube itself will be stretched thinner (like a ballon) than i should be alowing sharp and pointy things to enter easier.

My theory is that if you run the tires 5 PSI/KPA/etc under the stated max then you are providing A) more space to expand into, alowing for a smoother ride, and B) putting a more flexible tire in contact with the ground and anything on it, plus a tube with more thickness in the walls.

These are just my thoughts and if any one has any corrections let me know.


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## chesterqw (Aug 1, 2007)

Zeus got tired of making lightning bolts i guess?


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## monkeyboy (Aug 1, 2007)

I find that kevlar belted tyres are no good if the rubber cuts too easily. All that happens is that a piece of glass will lodge itself into the rubber and eventually work its way through the kevlar belt.

You should try Specialized armadillo's before giving up on inflatable tyres.

http://www.specialized.com/bc/SBCEqProduct.jsp?spid=26586

They're supposed to have the best pucture resistance.


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## Coop (Aug 1, 2007)

I had good experiences with Schwalbe Big Apple, but these are pretty fat. A few sizes skinnier the Continental SportContact comes to mind. I ran these on a daily basis for about 2 years without a single flat.


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## jtr1962 (Aug 1, 2007)

I've decided to wait a bit because Air Free Tires (airfreetires.com) is coming out with the new Open Road series in 2008 which uses the new HR (high resiliency) material. The test data linked to earlier showed some 110 psi equivalent HR tires with a Crr in the 0.0078 area. This was without optimization. In this letter the company president posted on some newsgroup he said:_ "By using this formula we have cut the rolling resistance in half and by utilizing some new shapes and tweaking the formula a bit, we feel we can get the tire down to .005 or thereabouts."_

I have no idea how good the new series of tires will be, but even if they can't do better than 0.006 to 0.007 they will still be as good as many pneumatic tires.

A recent review of some of their current tires. Interestingly, in the winter the reviewer found no rolling resistance difference but in the summer he said the tires were about 2 mph slower. Some HPV coast-down data suggests that pneumatic tires roll worse in colder weather while the airless appear to roll better. I imagine then at some critical temperature there is no performance difference. I might not do too badly ordering one of their current series now but the Open Road series sounds like it's worth waiting for. I guess then I'll get new wheels and try the Panaracer Pasela Tourguards mentioned in post #16. By the time they wear out, the new line of airless tires will hopefully be available.


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## geepondy (Aug 4, 2007)

Flat tires is one of the reasons my hybrid has become my number one street bike. Sure I'll drop a bit on the average speed but in the end get just as good of a workout and have gotten one flat in about ten years.


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## jtr1962 (Aug 4, 2007)

geepondy said:


> Flat tires is one of the reasons my hybrid has become my number one street bike. Sure I'll drop a bit on the average speed but in the end get just as good of a workout and have gotten one flat in about ten years.


How much speed would you estimate you lose? Lately most of my rides have averaged in the 15.5 to 17 mph area. However, that includes slowing/stopping for obstacles or traffic signals. Unfettered, I'd probably average around 21 to 23 mph. I'm not sure I would want to ride anything much slower. As it is I wish my bike were much faster. Besides the workout, I find the sensation of speed exhilarating. I'll usually push it to at least 35 mph at some point in the ride.

BTW, the more I'm reading about this the more I'm thinking of going airless right now. It seems all the solutions to flats such as Armadillos, wider, heavier tires, Tuffy rim strips, etc. increase rolling resistance a good deal anyway. And the airless tires can be customized for a higher psi, which should reduce rollling resistance somewhat. In the review I linked to two posts above the person use Daytona HPs with a 90 psi equivalent. I might try the Daytona TTs with a 120 psi equivalent, but with a higher custom psi. They have a special at $50 a pair plus $5 to customize the psi. If they turn out to be no good for every day riding, I'll just put them on my second (emergency) bike. However, based on the reviews I've read the only drawback seems to be a slightly harsher ride, and higher rolling resistance. I'm hoping tires customized to perhaps 175 psi can eliminate the latter. I can get a sprung seat to reduce the former. Not needing to worry about patches of glass, or blowouts if I'm going 50+ mph on a steep downhill, would go a long way towards making my cycling safer/more fun.


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## geepondy (Aug 4, 2007)

I would say probably a couple. My average speeds are not as fast as yours. When I'm in good shape, on the road bike I might average about 17 mph at least on the shorter runs but it's largely in unfettered territory. On the hybrid, I rarely hit 15 but generally it's fairly hilly terrain and I'm not sure the downhill speeds can make up for the uphill climbs. Also I run what I would consider "moderate" 700x35's on the hybrid meaning they have a fairly smooth center but tread on the outside. This is suitable for my needs as I sometimes hit dirt roads. There are skinnier, less tread tires available for the hybrids but then again when one goes that far, why don't they just ride a road bike instead. Hybrids are pretty customizable though. I've seen some that were almost road bikes and some that were almost mountain bikes.

It sounds like you're into the speed exhilaration so I don't think you'd like a hybrid but it might be fun to try. You'd be able to hop on sidewalks with ease and have a much stabler ride over potty roads and sand, etc.

If it wasn't 93 degrees, groan, I'd take the bike out for a ride today but just a little too hot as well as very humid to chance it. Maybe if I was still 25.



jtr1962 said:


> How much speed would you estimate you lose? Lately most of my rides have averaged in the 15.5 to 17 mph area. However, that includes slowing/stopping for obstacles or traffic signals. Unfettered, I'd probably average around 21 to 23 mph. I'm not sure I would want to ride anything much slower. As it is I wish my bike were much faster. Besides the workout, I find the sensation of speed exhilarating. I'll usually push it to at least 35 mph at some point in the ride.


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## jtr1962 (Aug 4, 2007)

geepondy said:


> It sounds like you're into the speed exhilaration so I don't think you'd like a hybrid but it might be fun to try. You'd be able to hop on sidewalks with ease and have a much stabler ride over potty roads and sand, etc.


If I find one to try out I'll give it a go just for the heck of it. I did try a friend's MTB a few times. After coming back from a ride dripping in sweat I actually asked him what was wrong with the bike. He said nothing. The tires felt like they were low on air to me, and in general the whole thing just felt dampened compared to my road bike. It was as if my pedaling effort just disappeared. I'd guess a hybrid would be somewhere between that and my road bike. I'll also note that my bike is in pretty bad shape. The rear wheel is wobbly, the tires are old, the drivetrain needs tuning, etc. I wouldn't be surprised if I could ride your hybrid as fast as my road bike at this point. Once I get the new wheels/tires/drivetrain it'll hopefully be a different story.

BTW, your speeds are still pretty respectable both for your age and riding a hybrid. The majority of riders I pass, even younger ones in their teens or twenties, are lucky to be going 15 mph.



> If it wasn't 93 degrees, groan, I'd take the bike out for a ride today but just a little too hot as well as very humid to chance it. Maybe if I was still 25.


Same weather here so I just ride at 9 or 10 PM. I'll still be dripping in sweat after a 90 minute ride, but at least it's tolerable (barely). I can't wait for that nice, crisp fall weather to go on some nice 2 hour rides.


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## will (Aug 4, 2007)

I ride an old Schwinn road bide for exercise around town. I will also ride a MTN bike on ocassion on the same route. The big difference is the tires between the two, The road bike will keep rolling after you stop pedaling. The MTN bike seems to just stop, or slow down very quickly with the knobby tires. I have increased the air pressure to 75 in the MTN bike, that helps. A few years back I picked up a set of "city" tires for the MTN bike. They are basically smooth tires with an inverted tread. That made a big difference by reducing the rolling resistance of the MTN bike. 

The long and the short of it all - road bikes are fast on pavement, MTN bikes are good in the dirt. The hybrid bike tries to take a little of each.


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## cave dave (Aug 4, 2007)

In short, they don't work. They typically fall short
in most (or all) of the following categories:
- weight (too high)
- rolling resistance (too high)
- retention (they fall off the rim or slip around the rim)
- ride (harsh)
- cornering (little grip, squirming tire)
- wet weather handling

It sounds like you riding is way to aggressive to use them.

I had good luck using the Mr. Tuffy tire liners, and I use to ride through a shipyard every day. It was covered with bits of metal and glass, etc

I inhabit a bike forum and the Schwalbe are highly rated. Heavy and not very supple but very puncture resistant.


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## jtr1962 (Aug 4, 2007)

cave dave said:


> In short, they don't work. They typically fall short
> in most (or all) of the following categories:
> - weight (too high)
> - rolling resistance (too high)
> ...


Going down that list, at least with the tires I'm looking at, the areas they _may_ fall short in are rolling resistance, ride, cornering, and wet weather handling. Weight is comparable to clinchers according to the review, and lack of retention is only caused if the you get the wrong tire size. Poor cornering is really what will be the show stopper for me even if the tires measure up everywhere else. I'm not riding regularly on tires which might be dangerous. For $55 plus shipping I'll probably give them a try when I get my new rims. Worst case, if I don't like them I'll put them on my other bike, and get regular tires, perhaps with a slime strip. You may be right. My riding style may well be too aggressive for airless tires. No way of knowing though until I try them.



> I had good luck using the Mr. Tuffy tire liners, and I use to ride through a shipyard every day. It was covered with bits of metal and glass, etc.


I've read mixed reviews on these. Some people like you love them. Others claim they actually ruin inner tubes, increase rolling resistance, or give a very harsh ride. In fact, I've read mixed reviews on just about every product to reduce flats. I'm starting to think the only thing is to try out one thing after another until finding something that works. Lots of alternatives in this thread if the airless tires turn out to be garbage.


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## Wyeast (Aug 6, 2007)

jtr1962 said:


> I'm bumping this thread because I've starting riding a lot more lately, so I plan to give my bike a major overhaul within a month or so. First, I'll definitely be getting new wheels. I'm considering these. My main concern is that these only have 24 spokes compared to the 36 spokes I've used all my life. Is my concern warranted, or has wheel/spoke technology advanced to the point where a 24-spoke wheel can handle rough city riding? On the plus side, the 24 aero spokes instead of 36 round ones in front, plus the aero profile, should help. I plan to use my rear disc wheel cover in back as I'm doing now, so no real advantages there other than maybe lighter weight.


The need on spoke count depends greatly on your riding style, and the weight the bike is carrying. If you're sort of a regular joe who isn't carrying a lot of weight on the bike, you're probably ok with a quality lower-count wheel if it has deep strong rims, and preferably if you have good wheel builder at least go through and hand-tension the spokes. 

If you're a heavier guy and/or you carry a lot of stuff on panniers then you could be in for some grief by riding over rough potholes too hard.

Good luck!


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## jtr1962 (Aug 6, 2007)

Wyeast said:


> The need on spoke count depends greatly on your riding style, and the weight the bike is carrying. If you're sort of a regular joe who isn't carrying a lot of weight on the bike, you're probably ok with a quality lower-count wheel if it has deep strong rims, and preferably if you have good wheel builder at least go through and hand-tension the spokes.
> 
> If you're a heavier guy and/or you carry a lot of stuff on panniers then you could be in for some grief by riding over rough potholes too hard.


Right now I'm in the 200 pound area (trying to get down to 160-170) but never carry anything, not even an air pump or a water bottle. Hopefully I'll be OK. I don't see myself ever doing the sort of really long distance rides where I would need to carry heavy loads. Just not my cup of tea. I would however like go on somewhat further rides than I do now. The possibility of flats has actually prevented that since walking the bike 15 or 20 miles home wouldn't be very appealing, nor would I want to carry the tools to fix flats on the road. Another review of airless tires.


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## CodeOfLight (Aug 6, 2007)

If you have skinny road tires, and you are riding at speed in bumpy roads, you might be getting snake bite punctures. This happens when the tire compresses all the way to the rim, and the sharp rim will pinch the tube so much that it will puncture the tube. It is called snake bite because that is what it looks like on the tube when you take it out. It will look like two puncture marks side by side. You can buy a special anti-snake bite rim that will eliminate this kind of puncture. The anti-snake bite rims have a flat area on the rim where this pinch would occur. This distributes the impact against the rim to about 10 times the area it would have been, preventing the puncture.


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## soffiler (Aug 6, 2007)

jtr1962 said:


> ...The possibility of flats has actually prevented that since walking the bike 15 or 20 miles home wouldn't be very appealing, *nor would I want to carry the tools to fix flats on the road*...


 
Why?

I am a serious cyclist, and I believe this is the first time I've ever heard _anyone_ say this, ever. A kit to fix flats is small, lightweight, inexpensive, and easy to carry.


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## jtr1962 (Aug 6, 2007)

soffiler said:


> Why?
> 
> I am a serious cyclist, and I believe this is the first time I've ever heard _anyone_ say this, ever. A kit to fix flats is small, lightweight, inexpensive, and easy to carry.


Since you asked...

The kit is small enough but the air pump isn't. Nor do I have the strength in my hands to pump up the tires using a hand pump (I have carpal tunnel syndrome). Also, 95% of my flats are in back. Every time I've removed the rear tire there's problems getting everything back right (i.e. it's a 30 minute ordeal requiring more tools than a patch kit), not to mention the greasy mess dealing with the chain. On a more practical note I do a lot of riding in weather which is too cold for rubber cement to set properly. It's more problems than it's worth trying to repair flats on the road. Given that this is NYC, if it's too far to walk I can find a bus or train. Like I said, I'm not really a long distance rider anyway. The most I might want to go is 15 or 20 miles from home, even with airless tires.

Interestingly, my brother was also excited at the possibility of decent airless tires. He said he _totally_ gave up riding on account of flats. Unless you live in NYC you have no idea how bad the problem of flats is here. My rationale with fixing flats on the road is why bother since I might miss a piece of glass, and then flat again three blocks later. I can do a much more thorough job at home. Even doing that, I've gotten flats sometimes three times in the same day.



CodeOfLight said:


> If you have skinny road tires, and you are riding at speed in bumpy roads, you might be getting snake bite punctures.


I got snake bite punctures exactly twice in my life, ironically two days in a row, about two weeks ago. It was totally my fault for not seeing the potholes. The main cause of flats has been glass in the rear tire.

Honestly, after reading two reviews so far of airless tires by _serious_ cyclists, it seems they've improved a lot over what existed even ten years ago.


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## WNG (Aug 10, 2007)

Perhaps you should try cyclo-cross tires....

http://www.nashbar.com/profile.cfm?...re&estoreid=961&pagename=Estore: Outlet Store

Also, if you are upgrading your drivetrain to 10spd, you may need a compatible crankset as well, since the chain will be narrower and may not work with a 7-8 spd spacing.
If you have a 9 spd setup, it should be OK.

I'm an old road rider, used to ride in Queens and Manhattan, then S.I. before giving it up due to rotten roads. It was poor conditions back then, I can imagine how bad it is now. 
I managed to survive on 27x1" and 27x1 1/8" tires, and later 700x25. But punctures were a fact of life. Fixing flats become second nature and you develop a quick technique to it and keep messes to a minimum. Usually, one can patch a tube in under 15 min. It helps to have a minimum of tools, and a cleanly maintained bike.

As for hand-pumping tires, I still have my pair of Silca frame pumps, but I don't really rely on them anymore. I carry a CO2 cartridge filling unit with me.
It's small and sufficient enough to fill a tire to get you moving again. It'll support shrader and presta valves for road and mtb owners.

For cities, I now firmly believe a hybrid is best suited for everyday riding.
More rugged, and customizable to cope with the conditions. And if set up right, they aren't slow.
Even switching a mtb's knobbies for baldies make a hell of a difference rolling wise. 

My idea of a city bike:
A hybrid/cyclo-cross frame with V-brakes for powerful braking, 700c rims w/ 32-hole spoking (I'm old school, 16 spoke isn't going to cope with 200 lbs of rider), rolling flat resistant rubber, a 48 tooth max chainwheel, and 11 tooth min sprocket for good cruising speed, and a flat handlebar for comfort and control. Also a set a SPD pedals and SPD shoes so you can still walk normally.


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## jtr1962 (Dec 3, 2008)

I'm bumping this thread because I ordered the airless tires and after 14 months (!) they finally came. These are what I ordered, customized with the maximum 175 psi option. While I consider the customer service totally unsatisfactory so far I’m pretty impressed with the tires. While I’ll undoubtedly have further comments as I get more experience, here’s my take after the first ~250 miles:

Ride quality: At first the ride seemed somewhat harsh. I literally felt every imperfection in the road. However, the tires started to feel smoother a few days later. Perhaps the material flexing broke in much as a new shoe takes time to break in before it’s comfortable. Whatever the reason, at this point the tires aren’t horribly worse than pneumatics as far as ride quality goes. On smooth roads they’re great. On potholed roads they’re rough but then so are 110 psi pneumatics. They certainly sound noisier over bumps so they may give the impression of riding much harder than they really do. I don’t find significantly more shock transmitted through the handlebars than I did with pneumatics.

Traction: When I was putting together my bike I noticed that I could slide the front wheel on a vinyl tile floor. I attributed this to the mold release. Just as a precaution, I removed the excess material along the seam with a utility knife. This increased the traction. On the road traction is as good as any air tire, and should only get better as the tire picks up road grit. I feel perfectly safe on these tires, even riding in rush hour traffic.

Fit and ease of mounting: The tires went on fairly easily, and perfectly fit my rims. I highly doubt the tires will roll off no matter what I do.

Rolling resistance: Just as I noted regarding ride quality, I’d say these tires need to break in for a few hundred miles at least to realize their ultimate potential. After only about 50 miles rolling resistance decreased notably. Also note that these tires required the skewers to be tighter in order to keep the wheels from shifting over hard bumps. Prior to tightening the skewers the wheel moved enough to cause the brakes to slightly rub. I wonder how many others this happened to and they attributed the increased rolling resistance to the tire instead of the brake rubbing? Anyway, since the rims and drivetrain are new on this bike and need to be broken in, I can’t say for sure how the rolling resistance compares to pneumatics. After about 120 miles the bike was about 1.5 mph slower but a good portion of this could easily be attributable to the wheel bearings still breaking in as well as the chain/ratchet mechanism/bottom bracket still being stiff compared to my other bike. Now after 250 miles the rolling resistance seems to be even less. I really do think the airless tires have a somewhat long break-in period before they develop their minimal rolling resistance. Maybe the extra psi option does help rolling resistance considerably also compared to the stock psi. As the tires wear into the optimum shape from riding I’m sure this will help the rolling resistance even more. One thing to note which I mentioned earlier was that pneumatics more or less double in rolling resistance going from 80°F down to 40°F while the airless tires either decrease or stay the same (honestly, it seems so far they stay the same although others have said they roll better at lower speeds. Regardless, at some temperature airless tires will be as good or better than pneumatics. Although such tests are inherently difficult, I've roughly estimated the Crr of my airless tires to be in the 0.008 area. This isn't that much worse than even the best pneumatics, and right around where many touring tires are. And it's better than most MTB tires or heavy, flat-resistant tires.

So here's the overal grading comparing to pneumatics:

Ride quality:

Airless: B+ (slightly harsh over smaller bumps but not overly so, no squishy feel like pneumatics)
Pneumatics: A- (pretty smooth overall but sometimes "squishy" when you rise in the saddle)

Traction:

Airless: A
Pneumatics: A

No significant differences here

Fit and ease of mounting:

Airless: B+ (kind of a pain to mount but fit perfectly, must choose tire size matched to your rim width)
Pneumatics: A- (more forgiving of rim width and usually easy to mount)

Rolling resistance:

Airless: B+ (somewhat to significantly more than pneumatics depending upon tire choice, high rebound material solves these problems but not available for all tire sizes)
Pneumatics: A- (can be as low as Crr 0.004 but rolling resistance increases at low temperatures and depends upon keeping the tire properly inflated)

Ease of use:

Airless: A+ (no maintenance whatsoever once tire is mounted)
Pneumatics: B (requires occasionally topping off for optimal performance)

Flat resistance:

Airless: A+ (by definition you can't get flats)
Pneumatics: C (note this is based on my own personal experience, while methods exist to lessen flats they ALL increase weight or rolling resistance, and you still need to keep the tire properly inflated).

Weight:

Airless: A- (while my tires aren't any heavier than comparable air tires some models are)
Pneumatics: A

Lifespan:

Airless: A (by most accounts the model tire I bought will last at least 8,000 miles, some with the new high-rebound material have lasted over 27,000 miles)
Pneumatics: B (most tires last 3000 miles or less unless they have a heavy, high-rolling resistance tread)

Rim Protection:

Airless: B+ 
Pneumatics: B+

Despite what others have said, after 250 miles my wheels are still perfectly true and undented. However, I'll grant that over a really severe pothole I will get rim damage but then again I'll also get it with pneumatics. Hence my grade of B+ for both.

Really, the only issues with airless tires at this point are higher rolling resistance for some models and in some cases a slightly harsher ride. They match or exceed pneumatics in every other area.

Other than the horrid customer service there are no show stoppers to using these tires. From what I read you'll get much better customer service ordering the tires directly from the manufacturer (nu-teck.com) rather than airfreetires.com but you will pay more. I can only hope by the time these tires are worn out that there will be an even greater selection of these tires, and that the 700c narrow tires will be available in the new high-rebound material. A high pressure high-rebound tire would have less rolling resistance than most air tires.


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## jtr1962 (Dec 3, 2008)

Some pics of the tires being mounted:

http://i91.photobucket.com/albums/k318/jtr1962/RALEIGH/PA230202.jpg

http://i91.photobucket.com/albums/k318/jtr1962/RALEIGH/PA230203.jpg

http://i91.photobucket.com/albums/k318/jtr1962/RALEIGH/PA230204.jpg

Link to album with all Raleigh rebuild pictures


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## HarryN (Dec 3, 2008)

Hi JTR - Thanks for all of the info - I have been looking at airless tires myself lately. (not for nearly as serious of riding as you do)

My 11 year old has an old 20 x 2.xx in skyway bike that is very flat prone. Originally it was from the usual suspects - thorns mostly. I put in all of the anti flat gizmos - thick tubes, a kevlar strip (between the tire and tube) and replaced the strip protecting the tire from the spokes.

For reasons that escape all of us, including 3 bike shops, the tube likes to shift around just enough to bend over the valve stem, literally tearing out the stem from the tube.
We have tried a variety of tire pressures and tubes, and nothing seems to work, so in frustration / desperation, I am looking for an alternative.

I agree completely with the idea of ditching the tire repair kit. In this case a repair means carrying around an extra tube and a pump, so an airless would be wonderful.

I will look into the links you posted.

Thanks


Harry


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## TONY M (Dec 3, 2008)

Nice tires jtr1962!

How much do they weigh and I assume they would be suitable for really rough and slippery roads in the larger sizes?

I do most of my training on the turbo through the winter but I have a converted hybrid that I use on the roads when the weather is bad.


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## jtr1962 (Dec 3, 2008)

TONY M said:


> Nice tires jtr1962!
> 
> How much do they weigh and I assume they would be suitable for really rough and slippery roads in the larger sizes?


According to the specs about 390 grams which is about what a similarly-sized air tire and tube would weigh. I don't notice any more rotational inertia compared to air tires. Yes, the larger sizes with lower psi feel would be more suited for the rough stuff than these tires. This is especially true for those tires made with the high-rebound material. In fact, the available high-rebound tires are all in wider widths.



> I do most of my training on the turbo through the winter but I have a converted hybrid that I use on the roads when the weather is bad.


Great idea! One thing is for sure-I'll never go back to riding on pneumatics at this point. The speed penalty associated with airless tires isn't enough to bother me all that much, and the other advantages outweigh this small disadvantage.


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## Sgt. LED (Dec 3, 2008)

Can you just fill them with that expanding foam Great Stuff?

Be a funky heavy feeling...........


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## jayflash (Dec 3, 2008)

Luckily I've had few flats in the first 30 years of biking. In the last 12 years my whole family has been going through bad inner tubes. No glass or potholes, just phantom flats. I've tried several different brands and they all have to repaired and have air added regularly. I guess things even out after a time.


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## TONY M (Dec 4, 2008)

jayflash said:


> Luckily I've had few flats in the first 30 years of biking.


You're lucky! I had my latest one last Saturday and it was a pain to repair as it was freezing LOL. 
95% of the flats I get are from thorns piercing the tire and tube.


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## TONY M (Dec 4, 2008)

jtr1962 said:


> One thing is for sure-I'll never go back to riding on pneumatics at this point. The speed penalty associated with airless tires isn't enough to bother me all that much, and the other advantages outweigh this small disadvantage.


 
I like the sound of that jtr!

Thanks


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## Mike Painter (Dec 4, 2008)

jtr1962 said:


> Needless to say, this is seriously cutting into my fitness regimen. I still walk a few miles a day but it isn't enough.


You mention exercise in another post also.

If you are riding for exercise then weight and high rolling resistance is a good thing.
A bike is far more efficient than any other form of transportation and that is not good for exercise purposes.
Walk a mile at 4 mph or more and then do two or three on a bike and take your pulse.
Walking also tends to be more of a whole body exercise.


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## TONY M (Dec 5, 2008)

Mike Painter said:


> You mention exercise in another post also.
> 
> If you are riding for exercise then weight and high rolling resistance is a good thing.
> A bike is far more efficient than any other form of transportation and that is not good for exercise purposes.
> ...


 
It totally depends on how hard you are trying.
For me as a trained cyclist my HR is highest when cycling (even higher than running). As you have gears to suit you're optimum cadance it doesn't matter if rolling resistance is high or if you are riding it on the flat or a steep hill.

I fully agree that cycling can be very easy if you are taking it gently and that 4mph walking can be more strenous.

I no longer use HR but it hovers at 75-85 at 4.3mph which is my cruising speed on a treadmill but I rarely train at less than 170bpm when cycling and frequently train at 185+ for 20mins or more which is where the real fun starts. 

Its just one of these things that can be easy or hard depending on what you are after.


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## jtr1962 (Dec 5, 2008)

Yes, it depends upon exactly how hard you go. I DO walk pretty fast, something like 13-14 minutes per mile, and I'm sure that gets my heart rate going. However, I'm also sure that my HR is higher when I'm cycling unless I'm stuck in traffic where I can't ride like I want to. _Averaging_ 14 or 15 mph on roads where I often must slow or stop for obstacles means I'm getting a pretty good workout. On the plus side the slightly higher rolling resistance of the airless tires means that I'll get a slightly better workout in those situations where I'm artificially slowed down. On the minus side, it means I won't go as fast even if I'm getting the same workout. So far my best ride on the airless tires has been at an average speed of 13.6 mph. However, I haven't had any rides yet where I was really going hard and hitting little traffic the whole time. Such rides on air tires averaged in the 17 mph area. They should be around 15.5 or so with the airless tires. I'll be overjoyed if it turns out there's no speed difference at all.

BTW, I just tried the airless tires today in wet conditions for the first time. Not intentionally, but it started raining while I was cycling and I had no choice but to ride home in the rain. Anyway, no differences at all in wet traction between these and regular pneumatic tires. In fact, I might cautiously even say the traction seemed a little better than pneumatics. And it seems like the thin film of water on the road reduced the rolling resistance a bit also. In any case so far I'm thoroughly happy with my airless tires. Only thing is to see how they hold up long term. They only seem to ride better and roll with less resistance as I pile the miles on. The only real downside to the airless tires is the company selling them. Service is hit or miss. 14 months and 6 emails is totally unsatisfactory service but there have been people getting their tires in 2 weeks. You unfortunately never know which and this is why I recommend dealing directly with the manufacturer, provided they sell the particular model tires you want.

One other thing-cost. I paid $50 plus $5 for a custom psi plus shipping for two tires. This has since gone up to $70 plus $15 for a custom psi plus shipping. However, even at that price it's no more than decent air tires and tubes. Considering the tires last more than twice as long, it's a bargain actually.


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