Bicycle Tyre Retreading - almost infinite miles from the one wheel.

Picture of Bicycle Tyre Retreading - almost infinite miles from the one wheel.
001 Worn Tyre.png
I have developed a way to give, almost indefinite life to the humble bicycle tyre. It works best for the average person on the average bike with nice wide road going tyres. It's not suitable for heavy people, using thin racing tyres.

The caveat is that this process, assuming the average bicycle tyre costs anywhere from $20 to $80 - or more, it can be retreaded for about $2 a tyre.

On very smooth roads, the expected mileage could reasonably be expected to be about 2000Km - 4000Km per retread.

It's very easy to do, it can be done with the wheels in the bike, and one ought to allow about 24 hours for the process to finish.

Everything in life is a compromise - this process and materials are no exception.

We use NEUTRAL cure silicon sealant, to build up the worn tyre with.

This has some interesting properties.

After the tyre has been sanded, when applied properly, it is extremely adhesive. It STICKS to the tyre.

It has a low shear strength compared to normal organic carbon based rubbers - meaning that building it up into a "thick retread" is not especially worthwhile, unless you and the bike are light and the tyres are fairly wide.

So the recommended build up is for a shallow dome, at best about no more than 2 or 3mm above the original tyre profile.

The optimum conditions of longevity are for an light to average weight rider, on a bicycle with nice wide tires, on smooth roads - doing the daily commute and travelling etc.

The heavier the rider, the more sharp sharp stones and very coarse gravel, and the more aggressive the riding style, the shorter the retread will last.

And the truly interesting bit.

Silicon rubber is extremely hydrophobic - it chemically repels liquid water.

This means that while you end up with a NICE long lasting retread that works very well on smooth dry roads and paths, when those roads are wet, the effect is that the silicon, while it deforms over the surface of the road, it molecularly repels the water on the surface of the road.

The effect is much like trying to walk through a kitchen with cooking oil spilled on the floor.

You can ride across wet patches, provided the road is level, you bike is within a few degrees of being upright, your not cornering, braking or accelerating, and you do it very very carefully. But for all intents and purposes, regular riding on these retreads in the wet, is impractical and unsafe.

The good thing is that there are some 500 million plus bicycles, and for most people, in most parts of the world, most of the time, most of their riding is done and can be done in the dry. There are also many people who tend to have seasonal weather, who can swap over to regular or wet weather tyres for the season, or can travel by other means, or can wait it out for the occasional shower to pass.

That makes this retreading system, suitable for about 95% of the people, about 95% of the time.

I myself live in an area, where in an average 30 day period, there may be about 630 hours of dry good riding weather, with perhaps 10 hours of rain. That is about a 98.5% riding time.

The back stop is that while the silicon could be compounded with silica flour (ground sand) or carbon black, to make it grip better in the wet, compounding it reduces the the tensile strength of the silicon rubber making it unsuitable for retreading the tyre.

There is commercial potential there, but my knowledge of compounding silicon adhesives, leads me to believe that the benefits of the adhesive / sealant - and the polymerisation of silicones, cannot be reconciled. Either one has a cheap, easy to apply and durable retreading system, or one may be able to achieve "carbon rubber" like wet weather characteristics - but the silicon rubber ends up like soft cheese. 

One may be able to mix in SOME silica / silicon flour / ground sand - to improve the wet weather grip, but I think it's a degree of proportion. The addition of SOME may lead to a big improvement in wet weather adhesion, but too much, may make the silicon soft and worthless.

As it stands, you could probably retread your tyres 10 or 20 times or even more, and this is a substantial saving on resources, such as time, money, and mechanical efforts.

The tyres in terms of longevity, will last longer if you keep your bike out of the strong sun, where ever possible. UV protection with a wipe over with some ArmorAll is a good idea.

The safety issues.

You now have a way to have near infinite retreads with your bike tyres, with the only real caveat that you CAN NOT ride it on wet surfaces.

One must also be mindful that tyres were intended to provide good service, not indefinite service. Retreading them annually for 30 years could be regarded as having gotten quite a great deal of extra service from them... Though 30 years on the same tyres might be pushing it a bit, 10 or 12 years of regular retreads, is entirely reasonable.

Tyres ought to be thoroughly inspected on a periodic basis - weekly seems to be fine, for damage, such as tears, cuts, bulges, cracking, fraying, separation of the carcass and tread etc., and replace them if necessary.

And don't ride on them in the wet.

This idea "may" have real commercial potential - but I decided that it's best provided in the public domain, and because it's real basic corner store tech - where anyone and everyone can do it, it's SO easy and low cost - in regards to our current "opportunities" in the global sense, it's necessary.

More people on bicycles more often = good. Better bicycles lasting way longer = good. One set of bicycles tyres lasting as many as 10 or 20 sets of bike tyres = very good.

These are the issues we need to consider.

So retread with gusto and enjoy the benefits of corner store tech!
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onemoroni110 months ago
What a novel idea and I appreciate the research you did.
copperaxe1 year ago
Interesting concept, but reading the comments I must say the feasibility vs reasoning is bit skew from your reason-to-do. Silicone is rarely (I've never seen an example) enviro-friendly, and indeed slick when wet. Adding grit to the mix would fix that issue and if you find biodegradable silicone then you won't pollute the environment with the small flecks of toxic silicone that the small animals would eat, or end up in the central pacific gyre when rains do hit the streets and wash the bits into the watersheds.

Personally I'm not an environmentalist, I have no problem tossing something in a landfill if it cannot be fixed or rebuilt. I would suggest for retreading the tires; instead of buying a container of toxic chemical that is used in an application not intended by the manufacturer, that eventually ends up in the environment as pollution and garbage. Use the money to buy a replacement tire made of recycled rubber, or wedge ball bearings coated in rubber cement randomly in the new treads. Helps vary the wear pattern and prevents over wear of the rubber as the metal takes some of the abrasion while only slightly affecting traction. Ball bearings can as the tire wears away, be repositioned. I find doing this helps to use some of the outer treads before the center goes completely bald.

Studding the tires as Zaphod Beetlebrox suggested is a start but I would heavily modify any stud you choose into a short point with a barb or two then next time you come across a tire in the woods ( or rainforest ... J/K ), take that tire and cut the tread section off into strips that could be forced onto the small spiked and barbed studs. This way at least you can help the environment by removing garbage that can be used in a modified condition similar to the intended use.

Side question though how much silicone is wasted by application then running the tire through the template?

Have you considered testing this as a preventative measure instead of a fix? I'm thinking (if you have silicone quantities sitting around) using the technique you have going here, using a compound that adheres readily to rubber, mix the compound with fine grit and force the compound into the treads of a new tire (think like grouting a tile floor). You have the added benefit of longer wear and traction (traction on polished concrete type surfaces at least) because of the compound mix but not loosing the benefits of the tire treads itself.

But thumbs up for exploring possibilities to a somewhat common problem. Being an American myself as soon as the time was bald enough to pop or spin my bike from under me I replaced the tire. But longer lasting tires or the option to extend use is working for me.
Wroger-Wroger (author)  copperaxe1 year ago
I had not thought about the environmental aspects...

As far as I can tell, they are heavier than water, more or less inert and non toxic and given that the dirt and most of what is plant life is made of silicon anyway, I don't think it's going to be an issue.

It will settle where it sheds, and if if does wash anywhere, it will soon settle to the bottom to chemically break down back to silicon and oxygen anyway...

Which is different to plastic bags and all....

I don't know... If you find out more, let us all know.

See I kind of see it like this.

Do I drive a car, with the inherently high environmental cost of making it, driving it, keeping it running with spares, and or disposing of it....

Or do I use my bicycle, with it's high mileage low cost and very good environmental credentials....

And do I keep on wearing the tread off otherwise good tyres with good carcasses (fabric and rubber), and then keep on throwing them out, when the other 90% of the tyre is just fine and a good retread will do.....

So do I pick the most cost effective - the least of the lesser evils, of the least evil transport mode, to keep myself mobile, or do I keep on tossing out structurally good tyres and replacing them with new?

In the scheme of things, is the silicon retread, really that bad? Or is it the least bad option out of many far worse options?

This issue is open to argument.

I will however be blending in some silica flour (ground / powdered sand) in with the next batch and we will see - with different blend ratios, how the wear issues come along and to hope that the hydrophobic nature of the retreads can be greatly reduced.

It's a good thing I am so big and a bit fat, and the tyre lasts such a short time...

They do anyway, silicon rubber or normal tyres all wear fast on the contact patch on the driven wheel, under me...

So this is good.
fred271 year ago
Whilst it's great that you're preventing a tyre going to landfill, that's a lot of effort to create a death trap. There's no way most cyclists can guarantee they'll never encounter any water.
Wroger-Wroger (author)  fred271 year ago
An absolutist perspective, serves no purpose.

Where I live, the roads would be wet for about 10 hours per month.

This means that for the other ~630 hours of the month, the roads are dry. Those are good riding times. The idea is not to guarantee 100% dry roads, ALL of the time, it's to work within ones circumstances.

By saying that just because one will occassionally get red lights, that one ought not to travel.

What the issue is that silicon retreading, gives a very economical way to keep your tyres going almost forever, at very little cost. In the wet, they behave like trying to cross a kitchen, with a smooth hard floor, that has had a pot of oil spilled across it.

You can ride your bike in the wet, provided it is within a few degrees of being totally vertical, that acceleration and braking is delicately done, and cornering is very very slow, and gentle, and the road is more or less dead flat.

In other words, it's not terribly safe, your margins of error are very small, and to travel in the wet, is not terribly practical, and there is quite likely to be many requirements such as hills, tight corners, the need to turn and brake etc., that make the riding of the bike in the wet, unadvisdable.

But you can roll in a straight line across a wet piece of road, provided it is dead flat and you do not do anything other than the most careful of manouveres.

So back to the opportunistic perspective.

There are a great many areas of the world that have very little rain. Or that it's almost always dry.

There are many people who only travel by bike when it's dry.

There are many many people who may choose to commute daily by bike, who also have alternative means of transport, when it is raining.

Proportionally speaking, this means that out of the 500,000,000 plus bikes currently on the face of the earth, that about 90 - 95% of them, are able to be ridden 90 - 95% of the time - on bikes with the silicon retreads. And for areas, that have definite wet and dry seasons, one can have the silicon retreaded tyres that are for the dry season, and dedicated wet weather tyres for the rainy season.

So for some people they may be able to retread their tyres, 10 - 20 times more or less for the cost of ONE new $20 tyre or way less for an $80 tyre.

For almost all people, almost all the time, almost everywhere on the face of the earth, this retreading process, is an excellent way to keep $$$$ in your pocket, and your bike on the road.

For me I can ride my bike for about 630 hours per month, and I can walk or put off the riding for 10 hours of the month.

For me, retreading my tyre for $2 a wheel, on the bike, over night, instead of paying $20 to $80 a tyre, along with freight, and removing the wheels, dusting the tubes etc., for me, this is an excellent upgrade in extending my tyres lives.

I refuse to think in blinkered terms, of the ONE restriction, as an excuse to totally wipe out all of the advantages and opportunities, that this process does have - and that it does present to so many other people, all around the world.

There is estimated to be in excess of 500 million bikes in the world. This process is very advantageous to most of the owners and riders, who CAN ride their bikes, almost all the time, with this retreading process.
Where are you living? I'm in south west Sydney and it would be lucky to be DRY for 10 hours a month at the moment.
Wroger-Wroger (author)  caarntedd1 year ago
West Vic - and it has hardly even dampened the dust in like 4 months....
I don't know about most of the people in the world, but I think rain,snow,sleet, any other forms of precipitation are very common. especially if you are riding to work and then having to walk you're bike home if it rains.
Have you actually "tested this theory". 

Much of the worlds land surface is desert, or minimal precipitation, or temperate climates.

Many people are dry weather / recreational riders only.

Many people do use alternative means of transport in the wet....

Many places have predominantly seasonal raining.

Many riders also CAN wait out the rains, or follow the weather forecasts, and plan their travelling around the weather.

And the small percentage of the actual riders, who have to commute, in places with regular rains, by riding in the rain, who have no alternative transport, or no option of waiting out the rains etc., they do not have to use the silicon retreads.

Perhaps you would care to research this, of the capital cities of the world, and their annual days of precipitation, and the estimated amount of dry weather riders, and the dedicated all weather riders.

Then on a statistical plotting model, there will be a enormously huge proportion of people who CAN use this retreading method, than those who can't.

This is all this system is good for.

Those who can and do want to use it, who see it as being to their advantage, and I see no point in arguing for those who cannot use it, who do not want to use it, and who do not seen it as being to their advantage to use it.

What can I say?

The principle benefits, and the circumstances, and the decision to use it, are the best decided by the individual, who may consider that all things considered, it is beneficial for them to use it.

When I state that it is great for people who can use it, and it's not suitable for people who must face riding distances, irrespective of the weather - then that's it.

This has all the logic of if you can't breath anything other than air, then don't stick your head under water.

All of the information I have provided, is to facilitate the end users making their own decision - and citing one particular set of circumstances, do not mean they apply to everyone else.

I know for me, that I can quite easily acquire all the benefits of this system, and the one drawback is able to be accomodated.

In fact I'd say that there is a large proportion of cyclists, who are in a similar position, who can benefit from this.

And these are the only people who really CAN use it.
Wroger-Wroger (author)  fred271 year ago
Death Trap is an interesting word. I prefer to think of the term, "Stupid".

Because if a person who cycles a lot, in the dry, on tyres that are not suitable in the wet, instead of waiting it out, or driving, or walking or catching public transport, or using the spare wet weather bike - then they are in fact an idiot, and deserve a Darwin Award, for being just plain stupid.

This is entirely their fault, and has nothing to do with the retread.

Kind of like using the hair dryer in the bath and blaming the electricity.
MaskMarvl1 year ago
I have an idea... What if you pre-cut some strips of plastic or cardboard in the shapes and sizes of the original tread, then after you perform the re-treading and before the silicone cures, you insert the strips into the silicone. Then remove the strips after it's cured.

Then you can actually call it "Tire Re-Treading" :)
newb1 year ago
its cool but its not really retreading, since you end up with no actually tread just a flat layer of silicone which can apparently leave you stranded with a useless bike if it starts raining, seems like it would be safer to simply replace the tire since a decent fall can end up costing quite a bit more than a new tire.
I use this silicon all the time at work. It comes in several "colours" each with different properties. The clear you used is a sealant, ment to be soft & flexable but doesn't have much strength. The white is an adhesive/sealant, bonds much better to most surfaces & has better tensile strength. The black is same as the white but less bonding power. It is quite strong & stands up to higher temperatures ( not relevant here) but does match tire in colour. You might try them out & see which works best. This silicon is often refered to as RTV (room temperature vulcanizing) in North America. LOVE THE IDEA !!!
shteef1 year ago
$20 - $80 is quite expensive for tyres, my local Target and K-Mart do bike tyres which have tread for $4.99 in a good range of sizes. They are probably crap but they must be better than a layer of silicon sealant.
Wroger-Wroger (author)  shteef1 year ago
Why must they be better? Upon what do you base your opinion?
Wroger-Wroger (author)  shteef1 year ago
We also need to think in terms of the USA's position. That the USA is actually insolvent. The products arriving from China etc., is only available because of cheap energy. The cheap tyres, actually are coming with a HUGE environmental price tag.

And what your getting at that price, is not what it's costing everyone, globally.

This disposable / throw away society is paying a HUGE price, and the conditions are going to get WORSE.

How you have it in the USA, is not how it is for a majority of the worlds population.

2/3rd;s if the people in the world live in poverty, hunger, the lack of clean water, health care, and your $5 here, may be a weeks wages there.

So being able to retread your only form of transport, for 1/2 a weeks wages, instead of a weeks wages, may in fact be a great idea.

I try to look at things in terms of everyones position, and how these things can benefit many, instead of my own position, and think only of myself - without including how my life style choices impact on everyone else.
Wroger-Wroger (author)  shteef1 year ago
Yeah you may be right.

But in Australia, we have the "Great Australian Gouge" where anything imported, or if it's imported with a fancy brand name, is expensive to very expensive.

Your $5 Asian tyre there, is our $20 tyre here.

Expensive tyres from Europe, the USA etc., do cost "quite a lot" but they have things like standard high pressures, kevlar belting, puncture resistance etc.

There is also an old maxim, that "You get what you pay for."

So if people are doing high distances, in mostly dry to temperate climates, on "good quality high pressure tyres - with Kevlar belting etc.", there are definite benefits in using the better tyres with the retreads.

Also to take a step away from bottom dollar price point thinking, there are the other costs.

The environmental costs of making the tyres (mining, transport, metal, oil products etc), the environmental costs of throwing tyres away that are still reuseable, the cost in time and fuels to go and get the new tyres, the time spent in changing the tyres over, etc., etc., etc.m or paying someone to do all of this for you.

Then multiply these costs for say 10 sets of tyres over say 10 years - where as on monetary costs alone, your looking at $100 worth of tyres (20 of them), without the hidden costs, of ALL of your time, effort and expenses on top of this, where as 20 silicon retreads cost about $25 - and I am still on the same set of tyres.

I mean this is a good deal.

bcavaciuti1 year ago
the problem with wet is a very real one in England when 50% of the time it is raining or wet so its not viable in England but if you can come up with a solution to the wet then it will be brilliant
here's my idea for testing different compounds: get a belt sander or rotary sander to simulate the abrasion of the road accelerated to sensible times (for testing) then cut up a worn out tire into short strips and attach (glue, screw, nail...) these to wooden blocks. then coat them with the compounds and test to see if they stand up to the abrasion. then you can patent your idea and start a business (wroger's magic tire retread-er) while giving me a slight cut of the profits for providing the method for your success hehehe.
Wroger-Wroger (author)  bcavaciuti1 year ago
I see the issue commercially, that cheap neutral cure silicon sealant, works very well for retreading tyres, that are to be used in predominantly dry climates.

I also think given the many benefits of this system, in enormous amounts of direct and indirect ways, and given that we are actually IN THE PROCESS of the collapse of the food chains, the lack of potable water, global poverty, hunger, resource scarcity, peak oil, polluted food, air, soil, water ways etc., etc., etc..

I really do not want to squander the TIME to get started on this, and real wealth, is the giving of this to many, not taking the time and bearocratic BS, to license and patent it all around the world and then to police it....

It's so easy and so cheap and so cost effective - it really is corner store tech.... I do not even want to bother trying to contain this.

In loose terms given that there are some 500 million plus bicycles on the roads, if say 200 or 300 million people can use this system as is, and they can get say 15 annual retreads out of the one set of tyres, then the SCALE of the cumulative benefits are significant.

I also judge that real wealth is to be determined by how much you can give and share.
Hopefulone1 year ago
As Lord Drake mentioned, add some grit. A quick search turned up these options:
Thin layer of silicone, thin layer of dusted-on grit (maybe roll the tire along a long pile of grit), and you have traction in water. Of course you'll have to watch where you ride with your sandpaper tires...
Studded in the future? (i.e could you incorporate studs, and would they be able stay in). For $20 and a longer lasting tire that performs reliably all the time I think I'll stick with conventional tires. it's a good idea but I think it needs to be further refined.
snotty1 year ago
Someone try this with ShoeGoo! Maybe that will stick in wet weather.
Lorddrake1 year ago
would mixing some sort of particulate (like a well screened sand) into the silicone prior to applying it to the tire help to add traction on wet conditions?
Wroger-Wroger (author)  Lorddrake1 year ago
Yeah it would the question is "How much" for something approaching reasonable adhesion in the wet, vs. how much it will weaken the silicon rubber.

Silicon rubbers respond differently to organic carbon based rubbers, in that carbon black (soot) etc., strengthens the rubber, makes it harder and gives it a longer life and much protection against UV, and it makes the silicon rubbers, crumbly and very soft.

I think the same applies to silica flours (ground sand) and sand in general.

I am sure that you could add some as in measured quantities, of each and then do basic tests, and the most suitable mixes could be applied for road testing, but I think there will be a ratio of an improvement in grip, offset by a softening of the compound.
One.1 year ago
Well thought out, well written instructable. Good job! But as we know... There's no such thing as almost infinite :]
MrRedBeard1 year ago
How long does this last?
Wroger-Wroger (author)  MrRedBeard1 year ago
This depends upon your weight, the size of the contact patch of the tyre, the air pressure in the tyre, the surfaces that your ride on, and your style of riding.

If your commuting on very smooth roads and paths, and your riding style is modest, your tyres are larger and of a lower pressure (and not thin and hard racer types) and you don't weigh very much, I'd expect about 2000Km per retread or more. If the roads are very smooth, you might even get 3000 or 4000Km. If your heavy, the tyres are small, the roads are covered in sharp stones and gravel, and you race around the place, then you might get from 500 - 1500Km per retread.

Ideally, this is the every day riders solution, for ordinary people on ordinary bikes, doing ordinary every day things.

rimar20001 year ago
Very interesting, but the problem of slippery should be fixed, it is very dangerous. Maybe you could experiment some solutions.

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