Introduction: No More Flat Tires???
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.