I was sitting outsdie the Los Altos Starbucks, enjoying an Iced Late, when suddnly I hear a Pffffsssst!, and my front tire goes flat right in front of me..... The bike was just leaning against the wall!!! took 3-4 seconds for it to go totally flat.. what gives?

When I taken the tire off, there was nothing sticiking in it, i ran my finger inside it and it was nice and clean, and the tube had a little hole in it which didn't look like a cut, but more like an imperfection in the material (like an air bubble?).. I am happy it didn't happend while I was riding, but why did it happend? Is there anything I could have done wrong? are there better tubes I could try?

Thanks,

A.

Where on the tube was the hole? Inside or outside? If your rim liner isn't covering your spoke holes completely, the tube will expand into the spoke hole (and they usually have sharp edges) and will eventually result in a flat. I went for a 50+ mile ride to the beach and back a couple of years ago. Loaded my bike in the back of my Pathfinder and started home. pffssttt. My tire goes flat. Crappy rim liners were to blame. Use Velox rim tape if you aren't already...

The rims are coated inside and are smooth, no spokes holes.. and the puncture was on the sidewall about 15" away from the valve

A

Also, sometimes the inner tube can be put in incorrectly so that it's pinched between the wheel and the tire. I've seen this cause a flat when a bike was doing nothing but standing there.

This sounds quite bizarre. You mean that you don't have a tire liner or rim tape inside them?? How on earth do you get to the spoke nipples? Is it a carbon-fibre 4-spoke time trial rim, perhaps?

Man, you guys are tough on newbies.. Maybe this isn't the forum for beginners..
To answer your quetsion, the rim has some kind of tape or other plastic on it, that gives the inside a nice, smooths, molded look, and I am not sure how to remove it to get to the spoke nipples.. The question I had asked was a recomendation for tires and tubes...


A.

To get to your tire/tube question we will have to interrogate you a little further...

I would suggest www.mtbr.com for reviews of tires and tubes (and everything else for the bike/rider). It's a pretty useful tool for shopping. Not knowing your tire size and type, it'll be pretty hard for those in the know to recommend anything.

The cycling Gods saw you at Starbucks and had to punish you.

This is truley instant karma.

Thanks,

The tires are 700x23 C..

Hi Greg,

Amen *S*

That stuff down thar is called rim tape.

Not having rim tape or a tire liner doesn't sound bizarre at all. Mavic Ksyrium rims have no holes in the completely smooth outer wall. The spokes thread directly into tapped holes in the inner wall. No rim tape needed.

Came to this one a bit late. A couple of things need clarifying.

First, if, as you say, it was on the 'sidewall' of the tube, that indicates a pinch flat caused by incorrect placement of the tube. However, your description of 'an imperfection in the material like an air bubble' sounds more like the sort of puncture like WildHare described that you get from a combination of a highly inflated tyre and crappy rim-tape, where the tube expands into the spoke-well and bursts like a pimple, even if the spoke wells aren't exposed.

The fact that it went down so quickly indicates the latter. Pinch flats usually take a bit longer to deflate. Also, the 'pimple burst' flat can happen at any time - it happened to my bike not so long ago in a similar way to yours.

Your description of your rim tape sounds like that useless black rubber stuff that is commonly put on bikes out of the factory. If so go with WildHare's suggestion and replace it with the good Velox stuff (ask at your local bike shop).

Was it really on the 'side wall' of the tube or on the rim side?

Allister

Um, hi Bikinguy.