Sometime in 2013, I had an eastern burnout tire on my rear wheel (the bad kind) and of corse, I hit a curb and bang goes the tire, and crack goes my rim....

I go home to find I have no extra tubes or good tires, But I did have...
An 18in tube and a 2.1 tire rated 10-30psi from a kids bike I found next to a dumpster. The tire was rather new and thick though. I streached the tube around the rim and pumped it up to 40psi with no problem.
A month later I decide to pump it up to 90PSI cause you knoe 90psi FTW!

It lasted for a 2 months of dialing in 360s and feebles until I hit the same curb and BOOOOM. The tire was half way off the rim and a piece of the tube was 4ft away

TL;DR: 18 inch tubes are a fine if you don't have any others on hand.
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bought from: Mario.villegas90, robinson79
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