Armouring a Bicycle Tire for Final Puncture Protection.

Intro: Armouring a Bicycle Tire for Final Puncture Protection.

Puncture protection tires are available (quite expensive) which have either an inlay of thick elastic material or a web of strong fibres. Liners can also be placed between the tire and the tube. An alternative to buy one of this products is to cut the bead of old tires and mount them as liners inside of the tires to be protected. Check this site for more information: http://bicycling.about.com/od/bikemaintenance/a/avoiding_flats.htm

All these systems give some amount of protection. However, a piece of glass that is big enough will make his way through any of the above protections. I propose you here a cheap and hopefully effective alternative. Of course this armouring increases rolling resistance and weight. However, these effects cannot be noticed in my 20 inches folding bicycle and I really don't care.

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Material needed:

- old tires, thinner than the tires to be protected,
- self-retracting tape measure;
- an old brake cable

STEP 1:

Cut the bead of the old tires.

STEP 2:

Cut the tape. The length should be a bit longer that the diameter of the tire, the extremities will overlap.

STEP 3:

Cut the central knobs in order to make place for the tape. It may also work if you ignore this step.

STEP 4:

Separate one wire from the cable.

STEP 5:

Sew the tape to the old tire knobs with the wire. Alternatively you may try with dental floss or some other strong yarn, but it risk to be cut by the tape.

STEP 6:

Place the old tire inside the tire to be protected.

STEP 7:

Mount the tire and the tube in the wheel and inflate.

The tire is formed even without air. With an strong tape or many metres of tape it would even be possible to cycle without air at all!

Comments

[panjumbie]

Hey, when I was a kid and didn't have the money for a new tire I just stuck one old no good tire inside another on the rim and rode that way, sometime for months. The inner tire kept the outer one from coming off the rim while riding. Rode OK if a bit bumpy, but far better than riding on the rim with no tire! So if you try this, and your tire goes flat anyway, you probably can ride on the flat without worrying about the tire coming off. Note: this was on thin tires, not the wide ones that are more common now.

[sidmarx]

Steel tape works great until it rusts, breaks into sections, and pokes a hole in either tire or tube, whatever it's next to.

[m a r i a n o]

I'm sorry to hear that. Was the steel tape painted? I hope that the paint on my measure tape keeps rust away a bit longer. May be an aluminum tape would be a better idea.
The brake wire may rust as well, it would be better to fix the tape with other means.

[sidmarx]

Yes it was. My present meth. has been working for months now, with no internal friction flats either. Here's how: For a 20" tire get 20" of tire tread with beads cut away. Add a 24 or 26" mountain bike tube with valve cut out, pinching the tire tread to feed it into the tube. Pull the whole strip in and overlap the excess tube over the other end, making a liner ring. (the tread strip alone would wear against the inflated tube & eventually cut it.)
Caveat--my first try was with duck tape, not tube, and that also cut the inner tube, believe it or not....

[m a r i a n o]

Good method. You should publish an instructable on that.

[EsquireJoe]

If you don't have an old metal tape measure lying around, you could also try using some of those old aluminum blinds. They're about the same width/gauge.

[m a r i a n o]

Good idea. May be the tape is better because its resilience is higher.

[alxriz]

did you put the inner tube in contact with the sharp-edged tape? or added at least electrical tape inbetween?

[m a r i a n o]

The tape is sandwiched between tire and the old cutted tire used as lining. The tube should not be in contact with the tape or with any other sharp object.

[golddigger1559]

what if you stack more tires inside? that way you could have a semi-solid tire, then youll never have to worry about a flat again

[Prof. A. Z. O_Trope]

If you ride on very smooth surfaces, that's fine. But on any irregular surface, it will make for an incredibly jarring ride. That's why the original bicycles had those enormous tires -- pneumatic tires had yet to be invented, and a reasonably smooth ride required a very large tire diameter, especially on the dirt and cobblestone roads prevalent in that era. Only when Mr. Dunlop came along and perfected what is more or less today's tire technology could tires be reduced to modern sizes and still offer a comfortable ride.

With today's polymer technology, it's probably possible to make some sort of solid composite with similar performance, and such things may even be commercially available, but a solid-rubber tire is no better an idea today that it was in the 1800's.

[killbox]

not only bumpy, but pneumatic tires, make for a much more efficient rolling over bumps. a solid rubber tire will resist going over every bump and all that energy is lost, where as the pneumatic tire will resit too then compress a little and then spring back returning alot of that energy.

[Prof. A. Z. O_Trope]

Right you are! Those "bumps" are not only uncomfortable, a lot of energy goes into making them, and that energy can only be replaced by more pedaling. Whether it's a pneumatic tire or some kind of composite, it must have the feature of absorbing small bumps and then "springing back," as opposed to transferring the bump directly to the bike and rider, which is what would happen with a solid, essentially incompressible rubber tire.

[Advar]

Maybe an inner core similar to dense pipe insulation...?

[killbox]

those work as closed cell foam, so yes would help, but unless those cells are at or around 30psi its still going to ride like a bike with 2 flats i encourage someone to try it and bounce a normal wheel at normal pressure and any other method, and it it bounces 1/2 as high i would be surprised.

[Advar]

Good point. Was also thinking of filling a tube with expanding foam insulation, but think that idea would fall flat...
(Sorry)

[m a r i a n o]

You may. A tube with pressurized air would still be needed, you need some kind of pressure to keep the bead interlocked with the flanges of the rim.
Performance of solid tires is known to be bad, probably worst than that of my armoured tire

[Advar]

In-frelling-credible! Hitting dollar store tonight to try this out on spare bike...

[hcbethel]

These all might work to reduce flats, but how many flats do you get? And they are easy to fix. I would gladly sacrifice the time to fix flats for the efficiency of a light tire.

[m a r i a n o]

Your point of view is very reasonable.

I use the bike for commuting, high performance is not relevant. Reparing a flat under the rain, on the night, by very cold weather, or when you are late to come to work is anoying. Without punture protection I used to have several flats a year, and I didn't like them.