Four front tire flats in the space of a week....
 

...and I've only been on two rides.

Even more frustrating, I can only figure out the cause of the second one (glass). The first was a complete mystery - just a little hole on the outer edge of the tube, but no apparent sharp or hole in the tire. The third ripped during CO2 inflation (a great big rip -anybody have any tips on that one? Did the rubber freeze and get brittle or something?) and the last one is again a complete mystery - a tiny pinhole without any obvious corresponding problem with the tire.

Screw it - the tire has about 2500 miles on it - I'm headed to the LBS to get a new one.

Yep. But changing the tire didn't help me, so I went by the LBS today and picked up some new rim tape as well. Maybe that will help.

Getting a new tire might be a good move. Sometimes a tiny shard of glass or something hides in the tire and is impossible to find. Then it punctures the new inner tubes that you keep feeding it.

The CO2 explosion is almost surely operator error. If you catch a bit of the inner tube under the tire bead the rapid inflation will lift the tire bead off of the rim and you'll get a blow out. People argue endlessly about using CO2 vs. a pump but nobody ever mentions the need to be doubly careful to make sure the inner tube is safely contained within the tire caseing.

Look for a tiny bit of automobile radial tire wire - which will move in and out of the tire as the tube inflates.

Regarding the CO2 explosion, my advice is to use a good old frame fit pump, instead. I am not particularly strong, but I can get plenty of pressure with either a Zefal HP-X or a Blackburn.

Something like this. There wasn't an explosion - just a loud hiss, but I had had problems situating the tube in the tire because I was trying to do it without partially inflating it first (I only had one CO2 cartridge with me and I was afraid of losing too much of the gas). So probably the tube was not seated properly. I learned how hard it is to get a completely empty tube into the tire without bunching and folding. So now I'll carry two cartridges.

Just got back from the LBS with a new kevlar reinforced tire.

I blow into the tube just enough to give it shape before installing it in the tire. I also install the tube into the tire before I attempt to put either bead onto the rim. I still take the time to examine both sides of the tire all the way around the rim before inflating it with CO2. It's still way faster and more convenient than using a frame pump.

CO2 inflaters are for races where seconds count. And you accept the risk of exploding tubes, etc.

Pumps are for everyday people.

I had a similar problem in cycling in Chicago this summer. 4 flats in a week. Careful inspection failed to reveal the problem. After the fourth I thought this is just ridiculous. I took the tire out and turned it inside out and very carefully inspected the entire tire. I found the tiniest sliver of glass hidden in the tire...just enough poking out to cause the flats. Almost needed a magnifying glass to see it. Got it out and have not had a flat since

Modern tubes don't last real well either, not in the saddle bag. I've had a three occasions (one recently), where the replacement tube either had a mysterious leak I couldn't find (not even under water in two cases) or just split. On every occasion, the tubes were getting on to a year old and had spent that year sitting in my saddle bag waiting to be used. The bloke at my lbs, when asked how long a tube should last, reckons about 6 months, especially over summer. Bloody annoying, especially because you usually only notice when you're replacing a punctured tube.

On the other side of the coin, I've got some real rubber tubes from the nineties that STILL hold air. Modern cycling is better? Yeah. Right.

Richard

My LBS suggests the tubes be kept in the box in the wedge, as he says the rubbing of an unboxed tube against other stuff in the wedge, or the wedge itself, will cause the tube to fail. I don't know - it has never happened to me.

I always keep them in the box Dnvr. I've also had ancient tubes that didn't do it to me at all. Go figure.

Richard

Oh, yeah. I read some great advice last spring and I now incorporate it in my saddle bag. A cotton ball rotated through the inner surface of the tire may shed fibers on the offending projection. Especially if your hands are cold you may miss the thing. Or hot and sweaty.

Not necessarily. CO2 has worked quite well for me but I (can you please read the following out of the corner of your eye so the flat gods aren't offended, please?) don't get a lot of flats.

OK. You can look back now.
Being able to modulate the flow is important. With presta valves I also pre-inflate by blowing the tube up by mouth.


I like talcum powder on a tube. There are those that think this isn't needed and I don't care. I think it helps the tube get settled in the tire.

I put my spare tube in a ziploc plastic bag with a generous sprinkling of powder in it. And a cotton ball. And a wet-wipe for clean up.

I also carry a cell phone and $20 for the ride of shame if it comes to that.

That's an answer for the road bike forum not 50+.

A guy my age doesn't know how much time he has left. I prefer not to use up my remaining seconds hand pumping a frame pump and I won't even talk about using one of those wimpy little mini pumps.

I use a wimpy mini pump.
Good little guy.
Had a flat yesterday. (no. 11 for the year)

On Sale now:

http://www.performancebike.com/bikes...0_20000_400032

Regarding longevity of rubber tubes my experience with rubber powered model airplanes and rubber sculpture molds has enlightened me as to the degrading of rubber with heat. Makes me think I ought to look into some kind of heat protection for my own tubes stored in the seatpack.

All I can add is that you should also look for a small cut in the tire right at the bead. Really lightweight tires (200-gram folding) have very light sidewalls, and chafing can create small holes thru which a tube will poke out and bubble enough to introduce a tiny leak.

If I got four flats in a week, I would definitely replace the tire. Actually, it's a good idea to know why you got every flat. If you don't know, then consider chucking the tire.

+1 on those radial tire wires! Very common in the wet Pac NW. And I carry at least two tubes in a small plastic shopping bag (like the kind they put CD's in). Recycling, and saves space - the boxes take too much room.

Also, CO2 compresses too easily (otherwise, why put it into a cartridge? Why not just put O2 into the cartridge?). So a tire filled with CO2 will quickly lose pressure as it compresses again. CO2 is great for making seltzer water or for powering air pistols, but I think it's a lousy way to fill a tire unless you are on your way to a real floor pump already. Full-size frame pump is the best way to go. It also gives you a place to put a small bell for when you're on the MUP's without attaching a bell directly to your fancy carbon racing bike!

L.

I'm thinking you didn't get a real good grade in high school physics.

I hate it on club rides when I feel a need to rush , while repairing a tube... .. When you take a tire off, keep a mental picture of the placement of the tube vis a viz the tire.. Notice where the flat is located and inspect that specific area of the tire where the tube was damaged with close attention. .. Along with the rest of the tire.. Usually , when I get a flat immediately after a tire repair, it's likely a pinch flat. As you insert the bead . under the rim; be sure your tube is not twisted or protruding . I usually only partially inflate a tube and then release that pressure in order to help the tube assume a correct position within the tire , rather than possibly being twisted as it inflates. Just some actions that seems to help lessen the possibility of pinch flats.

I never took high school physics! I did take a freshman physics class. Everything was counterintuitive but could be proven mathematically. I never took chemistry, either.

So yeah, you're right, I'm not sure if it's CO2 compressing (which would make sense) or CO2 leaking out of the porous butyl that would account for the observation that any tire I've filled with CO2 loses pressure relatively quickly. (Relatively = more than a few hours, less than a full day). So I'm hoping you can explain why this is?

L.

also, there are heavy duty tubes that are thicker and more durable than the standard or low end cheap tubes

The reason such a tiny cartridge can hold enough CO2 to inflate a bike tire is because it's stored in liquid form. When it's released I'm told that it expands a gazillion times although I've never personally measured this.

CO2 will get you home but you'll have to reinflate, or at least top off, your tire tomorrow. I'm told it doesn't leak but chemically passes through the butyl inner tube. I don't understand that part but I know the tire goes soft so, by whatever method, it must be true.

As other members have suggested, make sure your rim tape is properly placed, and in good shape.

Carry a pump. Those co2 cartridges are expensive.

Continental Gatorskins. Expensive, but money well spent if you hate flats as much as I do.

OK, I stand corrected. I will now stick to the "chemical passage" theory. Thanks for explaining this, much appreciated - I'm an accountant/computer geek, not an engineer!

L.

Tubes can get holes worn in them from rattling around in the box, too. I've had good luck with dusting the tube with talcum powder, sealing it in a plastic baggie, and then putting the baggie in an old sock.