BANG! Flat tire

[johnridley]

Halfway home today my rear blew out. It sounded like a gunshot. I didn't have a spare tube (hadn't gotten around to buying one yet) and I assumed I'd just missed a sharp bit on the valve hole, which wouldn't be patchable (and I hate field patching anyway) and it was an hour walk, so I called the SAG van (J).

When I got home the blowout was on the backside, and it looked to me like I probably nicked it with a tire tool or something, but in hindsight, I don't think this tube ever saw a tire tool; I put the tire ON without tools.

I patched it and put it back on, and about 2 minutes later, got another BANG! right in my ear. The tube had blown out even more violently, the same distance the OTHER side of the valve stem.

Turns out the tire failed around the bead. These tires are quite thin on the sidewall and either they've just seen too many miles or I abused them. Could be the latter; the old rims were actually pretty tough to get tires on and off of, and I did have to work to get them off. But OTOH, the tire looks pretty bad along several parts of the bead.

Anyway, I still have the Race Lite that was on the front last year, so that's going on the back. That's easily got a couple thousand more miles in it I think so I'm probably OK until sometime next year (I'll be buying some new studded tires for winter).



Odometer: 15134
These tires went on at 12907 so the rear lasted 2227 miles. The Race Lites went on new at 5250 in April '06, off at 8459 to mount studs, back on at 9800 and off at 12343 miles in November '07, so it already has 5752 miles on it (it was on the front before).

I also found the new amber xenon strobe in one of the storage boxes from the basement, and got the power cord soldered on to it, dug the mounting plate from the bike parts box, mounted it all up and hooked it up.

Comments

[kevinnickerson.livejournal.com]

How do you feel about airless tires?

[johnridley.livejournal.com]

They're garbage in general. They'd be OK if your ride was 100% on very smooth pavement. Discussions on BikeForums bear this out; some who have tried them love them, some hate them, and when asked, the difference is straight down smooth/rough road boundaries. My route is quite rough, and even if the route were different, most of the roads I've ridden in the area, including in Ann Arbor, are not good enough that I'd want to ride airless.

When you hit a bump with a pneumatic tire, you have the air volume of the entire tire acting to absorb the impact. With an airless tire, you have only the elasticity of the material between the road and the rim. As a result they both ride rougher and they're much harder on rims.

Also, they have to be carefully matched to the rim, and they're hellish to get on and off the rims.

I really have very little trouble with tires. Some people on BF have many flats a year; some in bad urban neighborhoods as many as 3 or 4 a month. Even with this event I'm still averaging just about one a year.

[kevinnickerson.livejournal.com]

OK. I was asking because the tires on my bike have been flat for a couple years (maybe 15), and my memory was that they were always low, and it was always a pain to inflate them, and that's part of why I just stopped riding.

I had to ride icyfeetofdeath's bike a few weeks ago for a urine test (no joke), and enjoyed it a bit. Granted part of the enjoyment was how well her tranny worked. Twist grips, no staring down at the gears trying to line things up.

[johnridley.livejournal.com]

I saw your bike in the garage the other day, but not hers. Is hers a 3-speed or something? Internal gears are nice. No slipping chains, hardly any moving parts on the shifting parts that are out in the weather, you can enclose the chain in a protective case since it doesn't have to move back and forth, and you can change gears while standing still.


I'd really like my next bike to have internal gears. Unfortunately, A) you need horizontal dropouts so that you can adjust the chain tension, and B) the hub I am looking at (SRAM 9 speed) is $350 for just the hub. Shimano makes a 7 speed hub for $150ish, but it is filled with grease, and word is that below freezing the grease gets so thick that it doesn't shift worth a damn anymore.

I think I'll probably be riding my current bike for several more years though.

[kevinnickerson.livejournal.com]

Her's is a 21 speed, IIRC. External gears for sure.

[johnridley.livejournal.com]

OK, same as mine then. I assume that what you like is indexed shifting, where you click to "3" and it goes into "3", as opposed to the old friction shifters, where you hunt around for the gear you want.

[kevinnickerson.livejournal.com]

Exactly. All I've ever had was hunt and grind.

[dave-ifversen.livejournal.com]

I've had two flats this year - one where the tire looked like the picture you have (I suspect because I mounted the tire using a screwdriver instead of a tire tool - big mistake), and one where a sharp piece of metal from the rim cut the tube. The latter problem I fixed by smoothing/grinding/sanding all sharp spots on the rim and using a very stiff, adhesive backed cotton rim strip. Haven't had a flat since (knock on simulated wood...).