Commuting - Any idea what would have caused this flat?

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macteacher
04-14-08, 08:18 PM
Hi All,

I just got my new pasela's 1.125" tires. I used the bike the other day with a light load on the pannier with no problems.

I got up for my commute in the morning and I found my bike on the ground...(didn't know why as it has a kickstand). Anyhow, I put it upright, load my pannier (both combined they were heavy. Maybe 30-35lbs altogether? I never carry this much weight. I did not sit on the bike but yesterday it supported my weight of 160lbs...So I can't figure it out. Could it have been the weight of the pannier sitting directly over the tire? I've never seen a whole of this caliber before. Tube and tire are new have 1km of riding on them.

I roll the bike out of the garage and was about to get on, when I noticed the flat.

I did not hear a popping noise when I loaded the pannier.


http://bp3.blogger.com/_K_EoCIxFDoE/SAPvnFSC75I/AAAAAAAAAEc/DgMVU6FbzhU/s320/P1040541.JPGhttp://bp0.blogger.com/_K_EoCIxFDoE/SAP2JVSC76I/AAAAAAAAAEk/sC0OcgW1G-w/s320/P1040543.JPG
http://bp2.blogger.com/_K_EoCIxFDoE/SAQN2lSC77I/AAAAAAAAAEs/UWxGBI8nZVY/s320/P1040550.JPG


randomgear
04-14-08, 10:32 PM
The only time I have had a hole like that is when I had a hole in my sidewall.
Caused a nice loud BANG in my apartment when I pumped up the tire. I patched it and on my to work the next morning it let out again - straight through the patch. Since it was about 20 degrees out, and it happened in front of my LBS, I had them replace the tube. The mechanic noticed the tube starting to poke out of the sidewall. So, new tube and tire.
Check your tire, and good luck.

richardmasoner
04-14-08, 10:48 PM
The only time I have had a hole like that is when I had a hole in my sidewall.

Ditto. Check for a hole in the tire.

Another possibility -- your tube wasn't installed correctly. A portion of it might have been pinched between the rim and tire.


CB HI
04-15-08, 03:02 AM
It is a blow out, normally caused by a sidewall cut/tear (as noted by others) OR the tire was not fully seated and the tube bulged out between the tire and rim.

SDRider
04-15-08, 08:17 AM
It is a blow out, normally caused by a sidewall cut/tear (as noted by others) OR the tire was not fully seated and the tube bulged out between the tire and rim.

I've had properly mounted tires blow off the rim. Cause: Cheap Performance brand 700x23c road tires and tubes. Front blew off the rim as I was pumping it up. Rear blew off the rim on my ride home the next evening, I replaced the tube, remounted the tire and it was about to blow off the rim again when I got home. I took both tires back and had them credit me the full price toward some Continentals which gave me no problems at all.

ericthered
04-15-08, 08:46 AM
Might check the rim strip, I could not tell where on the tube the hole was located. A pushed over rim strip caused tiny star holes that I suppose could be a weak point under a larger load.
Eric

tate65
04-15-08, 08:56 AM
I have seen this with defective tubes. I was sitting home one evening after 3-4 commutes on new tubes heard this explosion in the garage only to find my tire flat, when I removed the tube it looked just like yours. I suspect there was a weak spot they finally failed and because of the high pressure it exploded.

macteacher
04-15-08, 04:50 PM
Thanks guys. I went back to the BS that originally put the tube in along with the new tires. They had no explanation as to what would caused it. That said, they replaced the tube free of charge. Hopefully it won't fail me tomorrow on my way to work.

ncherry
04-15-08, 08:14 PM
That looks like a pinch flat. When putting the tire back on sometimes the tube creeps under and around the hook of the tire. It usually doesn't blow immediately but after riding for a little while. If it is a pinch flat what you want to do is the put on the tire then before pumping it up check that the tube is inside the tire and not under the tire. Also make sure that the tire is properly hooked on the rim.

One other thing to note. If you have older rims (pre 7 speed?). Don't pump the tire past 90 psi. The older rims are not made to handle the high pressure tires. One gentleman on our double century blew 3 tubes before we figured that out (we thought he purchased new rims).

CB HI
04-15-08, 08:26 PM
That looks like a pinch flat. You Jersey folks must define pinch flats differently than any place I have ridden.

For everyone I know, a pinch flat looks like a snake bite. Caused by riding on a tire at too low a pressure, hitting a pothole or curb which presses the tube against the rim causing the 2 holes in the tube.

macteacher
04-15-08, 09:21 PM
One other thing to note. If you have older rims (pre 7 speed?). Don't pump the tire past 90 psi. The older rims are not made to handle the high pressure tires. One gentleman on our double century blew 3 tubes before we figured that out (we thought he purchased new rims).

Thanks for the tip. My bike is almost 20 years old...the rims are roughly 10 years old. I'll check the PSI before I leave for work tomorrow

ncherry
04-16-08, 07:21 PM
You Jersey folks must define pinch flats differently than any place I have ridden.

For everyone I know, a pinch flat looks like a snake bite. Caused by riding on a tire at too low a pressure, hitting a pothole or curb which presses the tube against the rim causing the 2 holes in the tube.
You are correct, I used the wrong term. I can't remember correct term.

CB HI
04-16-08, 08:17 PM
You are correct, I used the wrong term. I can't remember correct term.I am not sure that I have ever heard a term for a flat caused by the tube ballooning out between the tire and the rim. Maybe someone can clue both of us in or confirm that there is no common term.

genel
04-16-08, 09:16 PM
I've heard, read and used the term "pinch flat" for both pinching the tube during an install and pinching the tire while hitting a rock.

Only time I've seen something similar, I had about a 1/4 inch cut in the sidewall, and while the bike was just sitting in the car, after(!) a 35m ride, the tube blew out through that lttle cut. Looked exactly like that. Not saying that's what caused this though.

Mr. Underbridge
04-16-08, 09:23 PM
I am not sure that I have ever heard a term for a flat caused by the tube ballooning out between the tire and the rim. Maybe someone can clue both of us in or confirm that there is no common term.

Hernia? ;)