Singlespeed & Fixed Gear - 700 x 25 tire pop/burst Question

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View Full Version : 700 x 25 tire pop/burst Question


ColtJ
12-24-12, 05:43 PM
Hello,

First I would like to wish a Merry Christmas (Happy Holidays) to all and thanks for reading.

I plan on taking the bike to a LBS later in the week but am curious if someone can provide some insight on what happened.

On a family ride yesterday the wife's chain came off of her purple fixie, we always race the last mile or so and it came off during the sprint.

Today I took it to my shop to check the cog, slack and chain line as it was a little too easy to put back on the cog imho. After doing so, i took it out for a ride.

I rode it a few miles and then decided to get on behind the shop on clear pavement. As soon as I got up to speed the tire popped/burst. It made a pffff psssshhhh sound pretty loud. Seemed pretty weird.

notes:
-Tire pressure was at the recommended 90psi yesterday and these tires have always held pressure.
-Tried putting air and it will not inflate more than 10psi (obviously). No obvious hole, tear, etc..
-Tires: Kenda 700 x 25C
-No idea what inner tube is installed.

Could it just be a matter of poor quality parts?

Thanks.


Bat56
12-24-12, 06:28 PM
You say no obvious hole, but there obviously is a hole. Unless the valve is broken.

hairnet
12-24-12, 06:36 PM
Sometimes things like glass get embedded in the tire and don't immediately puncture.

If you remove the tube and try to inflate it any puncture or tear will become apparent. Use the tube valve as a reference point to find the object on the tire, checking the inside and outside of the tire


ColtJ
12-24-12, 07:42 PM
Sometimes things like glass get embedded in the tire and don't immediately puncture.

If you remove the tube and try to inflate it any puncture or tear will become apparent. Use the tube valve as a reference point to find the object on the tire, checking the inside and outside of the tire

Bold is probably the issue. I did not take time to inspect it but now that i think about it, we've ridden on a few roads with quite a bit of debris, glass, etc...

Sucks... but thanks.

Will update when I figure it out.

sinikl
12-24-12, 09:20 PM
i had an office staple in one of my tires (who knows, it may've come from my cube at work :P ) that took me a while to find the in the tire casing. i found it by rubbing a finger on the inside of the casing til i encountered the debris (ow, pricked my finger.... use gloves if you use this method and care about your hands).

The whole "in reference to the valvestem" thing works a lot better if you mount your tires with the label/a label (PSI spec, etc if there is no brand name mark that's conspicuous) on the tire sidewall at the same place as the valve stem when you install it. That way when you rip it apart and find the hole in the tube, you can start at the label on the sidewall and walk around on the tire edge til you find the debris. Also makes finding the valvestem easy when you are trying to add air.

thewilson
12-24-12, 10:13 PM
The whole "in reference to the valvestem" thing works a lot better if you mount your tires with the label/a label (PSI spec, etc if there is no brand name mark that's conspicuous) on the tire sidewall at the same place as the valve stem when you install it. That way when you rip it apart and find the hole in the tube, you can start at the label on the sidewall and walk around on the tire edge til you find the debris. Also makes finding the valvestem easy when you are trying to add air.
+1
this has helped me solve many mystery flats.

BoSoxYacht
12-24-12, 11:31 PM
Also check the rim strips. Make sure all the spoke holes are completely covered.

europa
12-25-12, 12:43 AM
Adding to the above ( all good stuff), when checking that the valve hasn't torn out, you sometimes have to pull and tug it a bit to open the tear.

I had a tube suddenly decide not to hold air once ... well, quite a lot more than once but finding the puncture in this one proved impossible. You'd pump air into it and watch it go limp. Even feeding the inflated tube through a tub of water failed to slow it, which was frustrating because I could feel the thing going down in my hands. Never did find that leak, the replacement tube lasted till the tyre wore out. :notamused:

sinikl
12-25-12, 09:14 AM
Hello,


On a family ride yesterday the wife's chain came off of her purple fixie, we always race the last mile or so and it came off during the sprint.



I just noticed the bolded part. Is she ok? I had a bike spit the chain when i was out of the saddle once, and with SPDs clipped in, it turned into a crash real fast. nothing like collapsing all your weight onto the stem to throw you off balance.

ColtJ
12-25-12, 11:03 AM
Thanks for all of the reply's.


I just noticed the bolded part. Is she ok? I had a bike spit the chain when i was out of the saddle once, and with SPDs clipped in, it turned into a crash real fast. nothing like collapsing all your weight onto the stem to throw you off balance.

Thanks for asking. Yes, she is fine, the chain deformed the little tensioner bracket, she just lost it for a sec and swerved towards grass on the sidewalk while she applied the brakes.

ColtJ
12-26-12, 09:17 PM
Thanks again for the replies.

I just took the tire and tube off and found the tear in the tube. Actually there were two tears and it seemed whatever tore the tube went straight through.

Also noticed a scratch on the rim and a tear in the tire's sidewall.
**Note: There is a different area not pictured where the tire bead is torn.

I am going to assume I should replace the tire as well as the tube but thought I would double check first. Same question goes for the rim.

Pics:

Tire:
http://farm9.staticflickr.com/8076/8312418951_e5a9c9cdef_c.jpg

Tear 1:
http://farm9.staticflickr.com/8214/8313468544_b827be7db6_c.jpg

Tear 2:
http://farm9.staticflickr.com/8074/8312418527_9ba1b2914f_c.jpg

Rim:
http://farm9.staticflickr.com/8079/8313468120_824f9deabc_c.jpg

Thanks for reading.

ColtJ
12-27-12, 02:46 PM
I put a new tire and tube, still not sure what cause the puncture/slit but am posting to basically put a conclusion to the thread.

Thanks for the assistance, it helped me find the slit in the tire as I may have other-wised missed it.

Bat56
12-27-12, 02:52 PM
I am going with quasi pinch flat. You were riding the bike with low tire pressure and hit something. That did not cause a flat but damaged the rim, the tire, and weakened the tube.

Then at some point later, the tube and tire were brought up to proper pressure. It rode fine like that for who knows how long, could have been one day could have been months or years, but then the right combination of circumstances caused that weak spot in the tube to finally give up.

Scrodzilla
12-27-12, 02:58 PM
Also, I'm pretty sure that's a low-buck CST Super HP tire, which aren't known to be very durable in the first place.

ColtJ
12-27-12, 04:15 PM
The tire was a Kenda K-152 which I know is pretty cheap.

I replaced it with a Bontrager self sealing tube and a Bontrager T1.