No More Flat Tires???

Introduction: No More Flat Tires???

About: I have always like building... now I have the skills and equipment to do some really cool stuff.

Go-kart, wagon, wheel barrow... anything with pneumatic tires can easily be made into run-flat or no-flat tires. I was making a push-car for my kids and one of my tires had a busted valve stem. I couldn't find the right size inner tube... So I got to thinking.

Can I use canned spray foam and make it a tubeless tire?

Here are some pictures and instructions on how I did it.

Step 1: The Tires...

This could technically work with any pneumatic tires. I have only done these wagon wheels. I am going to try a kids bicycle next.

Here is a picture of the tire that had the broken stem. I usually have this spray foam around.

I figured how much the foam would expand and not utilizing common sense or gloves (this stuff sticks to your skin like nothing else) I took the wheel apart and squirted the foam into the  mouth of the tire... turning the tire... squirting... turning... till I had filled about half of the tire. I know it takes about an hour to fully expand so I put the wheel back together, tightened up the bolts.

I came back the next day and gave the tire a squeeze. Squishy, hard in places... not good. I took the wheel apart and saw my issue. The foam didn't grow as much as I needed. I was going to put some more in to fill the voids... when I thought, "Stick the tube into the valve stem hole!" I put the rim back together and did just that.

I stuck the tube, that comes with the can of foam, into the valve stem hole and pushed the end around to the opposite side of the wheel (so the tube is in the tire as far as it can go) and started filling. Pulling tube out a little at a time till the foam came out of the hole. Stuck the tube into the hole and did the same thing on the other half of the tire.

Came back next day... tire had some foam hardened outside the valve hole and in a couple places around the bead (Part where tire and wheel meet) Easily broke that extra stuff off with some pliers. *(foam comes off the metal really easy, not so much for the tire... or your fingers)

Step 2: Conclusion

I am rather pleased with the results. The tire is nice and firm and rolls very smooth. The tires are firm with just a little give (Like when they are properly inflated).

I will re-post when we get some miles on the wagon and see how the foam holds up. Over time will the foam just squish down or will it start to break into pieces or did I just make the inner tube a thing of the past.

There are different kinds of foam... some more expensive that have softer qualities... this is a cheap and easy way to fix flats on things like this. Lawnmower, wagon, wheel barrow... most could be flat-free in a day.

*(I am wondering how they will work under power, like on a go-kart, the rims might just spin within the tires.)

Update: I thought I was the first to do this... but I guess not. Check here for someone else who did it with a riding lawnmower.



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    26 Discussions


    8 months ago

    you could also just take a plastic ring and put rubber on the outside and boom easy no pop tire

    NO, it does not work. I have tried both great stuff and the loktite (better) foams. Both wind up by being just a 'crash saver'. (You still have a flat tire, just not quite as flat.

    That 'Slime' type of tire patch stuff is what you want to use here. It will not solidify, but will patch up a (garden usage) tire even with some dry rot. It fights corrosion to make a good seal to the rim, as well. It stays liquid inside the tire, continually patching any leaks as they develop. Don't use that expandable foam. It just crumbles eventually.


    1 year ago

    similar issue. Will try the hose pipe idea. But has anyone tried this type of idea with silicon goo, like the stuff that fills bathroom cracks... Filling inner tyre with it.

    For a small portable electric wheelchair,

    I tried foam first, then I used a old stiff water hose. I just kept wrapping it around inside a hand truck tire that kept going flat. You have to make sure you get as much hose inside the tire as you can before you put the tire back on. I leave the tire halfway on the rim while I do it. It doesn't warp, flatten, or wear out like the foam. Next I'm going to find a smaller size hose at the hardware store for a bicycle

    hi there, did you ever do other tyres of wheels? I am looking to find a way to make some solid rear wheels for my power chair, I have looked every where to fing black tyres but with no joy, so thinking about DIY but problem is powerchair is some 250kg including me in it. so thinking that this much would just crush it! any ideas comments welcome, cheers, mark.

    Remove valve pin. Fill with "door and window" foam, replace valve pin and immediately fill with air to desired PSI. Drive around for about 15-20 minutes. Repeat this process until no more foam can go into the tire. You're done!

    Wrong type of foam... this "great stuff" is rigid foam, you want foam that flexes like a sponge. You need to have enough foam/density to support whatever weight you have in tire.

    This is a very interesting idea! But the air inside pneumatic tires act as shock absorbers as the air inside compresses upon impact.

    I worked at a tire shop that does this for industrial tires. It is just that, foam fill. However the stuff we used made the tires VERY heavy. Quite common for skidsteer tires when they're doing demo work. Never thought of doing this with insulating foam tho.

    Is it possible to use this tricky for bicycles?

    This didn't work. There formed a flat spot and they weren't round any more. Also when you put a load on the wheels for any amount of time the foam inside would break down and turn to dust.

    Where is the update? It has been 2 years. I am interested in hearing how it went.

    You can buy solid polyurethane wheelbarrow and hand truck tires, through online vendors and some hardware stores (home depot and ag stores often have them, but charge an awful lot). They sometimes also have pre-made wheel-and-tire combos with foam filling already done (semi pneumatic).

    For tubeless low speed pneumatic tires, I've had good luck just putting a pint or 2 of latex caulk mixed with windex into the tires and sealing them with it. It forms a layer in the tire and also will have some liquid "rubber" in there for a very long time.

    Most large tire dealers have access to fill tires with a balck foam that doesn't break down. It is used in off road equipment that works in puncture prone areas, like building sites where numerous nails end up on the ground.

    1 reply

    Okay... after a time... with the wheel just sitting the foam broke down and made a flat spot. So this didn't work. Might with different foam...