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I Hope I Don’t Get One Tonight

A flat tire.  What a buzzkill!

Most cyclists are prepared for a flat.  All cyclists hope that they don’t get one.  The odds are against us though.  Flat tires are inevitable.  It is not a case of “if,” but “when.”

On rare occasions inner tubes have manufacturing defects.  This causes tubes to split along a seam, or tear at the junction with the valve.  There is not much you can do to prevent inner tube failures.

A self-inflicted inner tube failure is the pinch flat, also known as a snake bite.

Puncture Pinch Flat

A pinch flat most commonly occurs when you run over something that causes the tire to deform enough that the inner tube is squashed against the wheel rim.  This puts two small holes in the inner tube, at the pinch points.

I said ‘self inflicted’ because pinch flats are much more likely to occur with under-inflated tires.  Bike tires leak over time.  You will need to add more air from time-to-time to maintain the proper pressure.  Run your tires too soft, and you will be snake bit.

I have been guilty of doing this.  I like to run my tires at between 80psi and 90psi.  Softer tires means a more comfortable ride.  I have let my tires get too soft, with predictable results.

In most cases flats happen because you ran over something sharp.  Roads are littered with sharp objects.

Bits of glass, either from broken bottles or shattered windscreens, are usually visible.  If you see it in time, you can avoid running over glass.  Unless you are riding at night, which is when I picked up this chunk.

Puncture Glass

Small stones are less visible.  It is worth examining your tires after every ride to remove any sharp stones stuck in the tread.  Before they work their way through the tire and into the inner tube.

Puncture Flint 2

Then there are the pointy things which are invisible while you are riding.  So small that a thorough search is often needed before you find the offending object, embedded in your tire.

The majority of my flats are caused by staples or Michelin wire.  Those fine bits of steel wire on the right come from steel-belted radial tires, which were invented by Monsieur Michelin.  Hence the name.

Given that most flat tires are caused by essentially invisible road debris. there is little you can do to avoid them.  Even “puncture proof” tires are not 100% resistant to being pierced by staples, Michelin wire and the like.

So learn how to repair a flat tire, and carry tire levers, a spare tube, and a pump or CO2 inflator on your rides.

And be thankful that we don’t have these in Malaysia.

Puncture Goathead Thorns