SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/bike-fix-flat-find-cause

Before you put a new tube in after a flat, what should you do?

Find and remove whatever caused the flat.

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  1. Add sealant to the new tube
  2. Find and remove what caused the flat ✔
  3. Pump the old tube up again

Why: A nail, thorn or piece of glass can still be stuck in the tire. Check the tread and carefully feel inside, or the new tube may go flat too.

Huh, didn't know that: Park Tool says to wipe the inside of the tire with a rag first, then feel carefully with your fingers.

The dad joke
Why did the thorn get blamed? Because it was looking sharp.
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References

Answer: Find and remove what caused the flat. A nail, thorn or piece of glass can still be stuck in the tire. Check the tread and carefully feel inside, or the new tube may go flat too.

  1. Park Tool: Tire and Tube Removal and Installation www.parktool.com/en-us/blog/repair-help/tire-and-tube-removal-and-installation
    The cause of the flat, such as a nail or piece of glass, may still be embedded in the tire or tread.
    Checked 2026-10-12.

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