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acorn
08-17-2011, 11:48 AM
I keep getting flats in my bike's rear tire. The tire itself seems fine, but the tubes keep getting holes. I even replaced the rim tape. What could be going on? I don't think I'm over-inflating. What should I check?

OneEighth
08-17-2011, 12:20 PM
Do you know if the tubes are getting holed in the same place? That would help you pinpoint where to look on the inside of your tire to find the sliver of whatever that has probably poked through and is causing your flats.
You can also run your thumb around the inside of the tire. Might get knicked, though.
Just in case---are you making sure that the replacement tubes are completely inside the tire and not caught between bead and rim?
Good luck.

JustinW
08-17-2011, 01:15 PM
Pinch flats, perhaps? Are you hitting a sharp-ish curb or bump in the road consistently with your rear wheel (perhaps while lifting the front off of the bump)? Easier to get these than you'd think. Given some of the road conditions around here (including transitions from path to road, sidewalk to road, etc.), I'm surprised we don't have more such flats.

Dirt
08-17-2011, 01:31 PM
Sometimes tires that appear good visually and by feel are just old and prone to flats.

SteveTheTech
08-17-2011, 07:28 PM
Good advice fellas,

What kind of a tire/tube/wheel combo do you have?
Any chance we can get some pictures?

Dirt
08-18-2011, 07:52 AM
Interestingly enough, the tire documented below never gave me any flats, which explains why I never bothered to look and see if it was worn out. Also oddly enough, I got a flat the first ride after putting new tires on. The bastards! Do as I say, not as I do

http://farm7.static.flickr.com/6182/6049900286_64feda5085_b.jpg

Another thing to note: You don't realize how much worn out tires slow you down until you put on new ones. It was kinda like someone removed the cinder block from my jersey pocket the morning after putting new tires on.

Hugs and kisses,

Pete

eminva
08-18-2011, 08:51 AM
All right, I've got to ask the opposite question . . . how do you know when your tires are worn out if you AREN'T getting flats? My tires have 3900 miles, show no bald patches like Pete's photo, although they are sort of "flattening" in the middle like in Pete's photo.

Thanks.

Liz

Dirt
08-18-2011, 09:13 AM
Great question. I'm sure there's a scientific way to know, but in general I look for a few signs that my tires are wearing out:

1) Many unexplained flats.
2) Visible flat spots, lack of tread or casing showing through. Dry rot on the tire is another sign... cracks in the rubber or casing.
3) The tires start to feel really slow. There is definitely a point where I can feel the tires holding me back. It kind-of sneaks up on you, though. It is a gradual thing. Slight inclines that usually are a breeze to power up become more labored.

Many people change the tires when they get a significant flat profile on the rear tire. I tend to ride them till they are dead, dead, dead... at least I do on the commuting bike. If it strands me, I can still make my way home one way or another. There's no way I'd head out for a 70 mile ride on the tire I photographed above. Definitely unwise. I didn't bat an eyelash at heading to work (18+ miles each way that day) with it though. I bought new tires on the way home.

Slight variation on this topic... Rotating tires.

Some people do it. I tend not to. The way you should rotate tires is this: Replace the front tire with a new tire. Replace the rear tire with the front tire. Throw the rear tire away. If you're someone who does not let their tires wear down way too much, this can be a very good way to keep fresh rubber on the bike. You always want your front tire to be the newest. Getting a rear flat is annoying. Getting a front flat is much more dangerous.

I had a front blow-out (defective tube) this week while riding quite fast on a downhill. I was riding the fixie, which makes it even more sketchy. I think I had a thread a few months back about getting 3 flats on the rear tire during a commute and I ended up riding home 9 miles on a flat rear tire... found the fridge empty, so I rode another 6.2 miles on the same flat tire to get dinner. That usually spells the end for the rim.... It was a good day for it to die. Oddly enough, the rim wasn't damaged. Bicycle wheels are amazing things.

Happy Thursday.

Pete


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I am here: http://maps.google.com/maps?ll=38.895210,-77.029702

Joe Chapline
08-18-2011, 09:58 AM
The last tire I replaced had a bulge in the sidewall, and that's happened with other tires. Something else to watch for.

americancyclo
08-18-2011, 10:27 AM
You might also want to check the inside of the rim, or near the hole for the tube stem. Sometimes you'll find a small burr that will put a hole in your tube, but they can usually be filed down without a problem.

As an aside, this morning as I was about to get on my bike I heard a strange noise, I went to pick at what I thought was a leaf stuck to my front tire, only to discover it was a huge flap of rubber. I made it home fine last night, and put her away safely. She must be stepping out on me under the cover of darkness. :rolleyes:335

Greenbelt
08-18-2011, 10:42 AM
All right, I've got to ask the opposite question . . . how do you know when your tires are worn out if you AREN'T getting flats? My tires have 3900 miles, show no bald patches like Pete's photo, although they are sort of "flattening" in the middle like in Pete's photo.

Thanks.

Liz

Impressive. That seems like a lot of miles. I seem to wear through tires in 2000 miles or less. (Course I probably weigh more...)

SteveTheTech
08-18-2011, 12:22 PM
http://farm7.static.flickr.com/6182/6049900286_64feda5085_b.jpg

Nice DoF and bokeh!

Most of the decent replacements I've had my eye on have a very small wear indicator built into the tread of the tire

https://lh4.googleusercontent.com/-DWdPA85LBCI/Tk1JR4eL2nI/AAAAAAAAh9U/Dmxwlds6uao/s912/IMAG0106.jpg

This is the closest thing I've got nearby currently. IDK why the internet doesn't have pictures of this but....

Dirt
08-18-2011, 01:34 PM
Impressive. That seems like a lot of miles. I seem to wear through tires in 2000 miles or less. (Course I probably weigh more...)

Totally depends on the kind of tire you're using. The speedy roadie tires, like I photographed before last me 2-3000 miles. If I'm lucky, I can get 5000. Touring tires can last much, much longer than that. I got more than 10,000 miles out of my Specialized Armadillos. I've got at least 5000 miles on my Schwalbe Marathon Extreme's (26x2.0 on the cargo bike). I found the 700x35c Marathon Extremes were less durable. They started showing wear after about 2000 miles.


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I am here: http://maps.google.com/maps?ll=38.895210,-77.029702

CCrew
08-18-2011, 08:17 PM
The last tire I replaced had a bulge in the sidewall, and that's happened with other tires. Something else to watch for.

Yeah, cracking in the sidewalls, and also I've noticed some of mine seem to get bigger in profile also.

I'm with Dirt though. My Cross bike needs new tires now. They look ok, but it feels like I'm riding with the brakes dragging these days.

nicegirl
08-22-2011, 10:32 AM
I'm glad I'm not alone on the OP's problem! Found the fourth flat in as many months on my back tire this morning, UGH! I've had the bike 3 years and the first flat in the series was the first flat period, so this is a weird, new, and annoying problem. I had the bike shop put in an extra rubber strip thingy (I just like to ride bikes, I don't actually know anything about them) between the tube and the wheel but alas. The bike shop said it had to do with how I was pumping the tire (I have the pump with the flip up lever, which they said was the wrong kind of pump). I was super careful when filling it up not to joggle the valve stem but no dice. I am ready to just buy a new wheel and hope that it's better.

acorn
08-22-2011, 10:47 AM
Mystery still unsolved. Bike mechanic says- no problem with tires, alignment, rim tape, etc.
My new theory is- my husband is secretly under-inflating my tires in the hope that I will think something is wrong with my bike and let him go bike shopping for me.

jrenaut
08-24-2011, 08:52 AM
I blame the earthquake for my flat yesterday. I found out about it when I was going to bed and went to hang the bike on the ceiling. Awesome to change my first tube when I thought I was going to be asleep in five minutes. But I was successful - made it in to work this morning uneventfully. Next up - trying to patch the tube I took off the wheel.

invisiblehand
08-24-2011, 11:57 AM
I keep getting flats in my bike's rear tire. The tire itself seems fine, but the tubes keep getting holes. I even replaced the rim tape. What could be going on? I don't think I'm over-inflating. What should I check?

(1) ** Read what Sheldon has to say. **
http://www.sheldonbrown.com/flats.html

If that doesn't help, here is my quick list ...

(1) Are the holes on the outside (facing tire) or inside (facing rim) of the tube?
(2) Are they "snakebite" flats? http://www.sheldonbrown.com/brandt/snakebites.html
(3) If outside, note the place on the tire where the hole occurs. If it occurs in roughly the same place, look very carefully for some sharp object on the inside of the tire. Sometimes this can be a piece of the tire -- wire or other material.
(4) If inside, note the place on the rim where the hole occurs. If the rim tape is cheap, I've noticed that the tape can sometimes slide when people use a lubricant to seat a tire.
(5) If you're desperate, I would check the outside of the tire looking for anything embedded in the tire. I'd remove the debris with a pin or something similar.

invisiblehand
08-24-2011, 12:06 PM
All right, I've got to ask the opposite question . . . how do you know when your tires are worn out if you AREN'T getting flats? My tires have 3900 miles, show no bald patches like Pete's photo, although they are sort of "flattening" in the middle like in Pete's photo.

The number of flats, as Dirt writes below, is probably the first signal. I generally look for tread, bumps, or other irregularities in the tire.

http://www.sheldonbrown.com/tires.html#replacement


1) Many unexplained flats.
2) Visible flat spots, lack of tread or casing showing through. Dry rot on the tire is another sign... cracks in the rubber or casing.
3) The tires start to feel really slow. There is definitely a point where I can feel the tires holding me back. It kind-of sneaks up on you, though. It is a gradual thing. Slight inclines that usually are a breeze to power up become more labored.


I've always found worn tires roll better since the tread is smoothed and the casing becomes more flexible such that rolling resistance decreases. In fact, there are people that shave their tires to "wear them out" faster.

http://janheine.wordpress.com/2011/06/21/summer-2011-bicycle-quarterly/

Greenbelt
08-25-2011, 10:54 AM
342

On the way home on Tuesday, my rear tire literally bubbled up. This picture shows a flat spot or bulge developing after the first few miles (hot pavement, mid-afternoon sun on the MBT).

By the time I limped in to my LBS after about 12 or 13 miles, the bulge was 3 inches long, and a half inch of extra tire depth. It felt like riding on a tire with a square spot -- made a lot of noise every rotation and bounced. Shop mechanics said they'd never seen anything like it, but suspected it was a design or manufacturing flaw triggered by heat.

These were there new tires I just put on a couple weeks ago. I wish I had taken a picture of the inside bubbles when we took the tire off, because now a couple days later the tire looks normal.

So anyways, I went back to a standard cx tire on the rear. There's no evidence of the front tire doing anything similar, so I left that one on for now. But I want my $50 back from specialized! Those were expensive tires to mess up after a couple weeks just because the pavement was too hot? Gimme a break. Anyone heard of anything like this?

Dirt
08-25-2011, 01:11 PM
The shop where you bought them should stand behind them. Specialized and their dealers have pretty good support. There are some manufacturers that do not, but Specialized has had a good rep from what I've heard. If you bought them mail order, you're probably SOL.


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I am here: http://maps.google.com/maps?ll=38.895386,-77.029838

Greenbelt
08-25-2011, 05:45 PM
Bought them online -- will send them a note with the picture and see what they say. If they don't respond, I'll chew out their reps at Interbike!

Greenbelt
08-31-2011, 04:24 PM
Update: Specialized replaced the tire that separated. It arrived today. Excellent customer service, and much appreciated!

356

Hi,

Sorry you have had this problem with one of our tires.

I have just placed an order to have a replacement tire sent out to you. Once you receive the new tire please cut the bead of the bad tire and dispose of it to prevent the tire from being used by someone that may not know the tire is damaged.

Thanks for using our products and have a great weekend.

Bob
Specialized Online Store Customer Service
Specialized Bicycle Components
1475 S. 5070 W. Ste. A
Salt Lake City, UT 84104
877-808-8154


________________________________________
From:
Sent: Thursday, August 25, 2011 5:03 PM
To: Store CustomerService
Subject: FW: Your Specialized Order 899075

Hi,

One of my new tires (see order info below) literally bubbled up on the road earlier this week. I have attached a picture from when it started, when it was a pretty small bulge out on the sides. The inner and outer sections of the tire separated and a bubble formed in between. The main bulge was about 3 inches long, with smaller bubbles going half way around the tire. My bike shop had never seen anything like it, and speculated that is was due to hot pavement. The other tire I bought has not had this problem, so I presume it was a manufacturing defect, not a design flaw.

Could you replace the tire or credit my credit card account for the $50?

eminva
09-07-2011, 09:24 PM
Okay, the bell finally tolls for me. I got my first flat this evening. I mentioned above that I had about 3900 miles on these tires; this is my first day back after vacation so the mileage is not much higher now.

The flat occurred about two blocks from home and I was rapidly losing daylight, so I walked the bike home to change the flat at home (although I had everything I needed on the bike). This is my first real flat change outside of practice at the Bike Shop flat classes.

For you neophytes out there, it went well! It only took me about 10 times as long as a normal person.:rolleyes:

Because I was at home, there was plenty of time to troubleshoot the cause of the flat. There was a little piece of glass embedded in the tire right at the valve stem.

Some observations:

1. The Old Man Mountain rack made the process quite a bit more difficult (it was the rear tire that was flat). The whole skewer had to be removed.
2. In the great outdoors during non-daylight hours, a helmet light would be really handy for this operation. Yet another reason to consider that upgrade.
3. In an abundance of caution, next time I'm in a bike shop I'm going to ask if they think it's time to replace the tires. It sounds like my mileage is pretty high comparatively; they don't owe me anything.
4. It's really unfortunate I can't find the grease removing hand soap at the moment.

Liz

5555624
09-08-2011, 07:44 AM
4. It's really unfortunate I can't find the grease removing hand soap at the moment.

I keep a pair of latex gloves with my spare tube and patch kit. They keep my hands clean when I change a flat away from home.

CCrew
09-08-2011, 08:17 AM
Must be the time of year for it. Took a flat this morning on the way in on M street.. Just after it started raining hard of course :p

20 miles on the tire.. gotta love it.

Greenbelt
09-08-2011, 09:17 AM
My wife got her first commuting flat this week (construction staple). I haven't put my new (replaced) kevlar tire back on. I did try an experiment with a regular tire, however. Instead of using a normal tube, I got a heavy "thornless" tube when I replaced my last tire. I can say two things: first, the thornless tube doesn't lose air hardly at all, and second, that thing weighs a ton on the bike! Really makes the bike feel heavy and sluggish. Don't know if I'd recommend except for very strong riders who don't mind the extra workout.

I'm hoping someone will manufacture the perfect tire for me, but I haven't found it yet: at 35mm CX-style tread tire with the kevlar flat resistance of the Armadillo (but that doesn't separate on hot pavement).