No kidding. I was averaging 10 miles/tube this summer until I replaced the tire with the hidden glass fragments. It had been quite a while since I had a flat before that too, and I guess I was too confident in my ability to replace the tube at the trailside.

I know, you are just trying to help. That is an honorable thing. Its all good...

Do you know what caused it?

Yeah, those can be a bear to find. My toughest one was a little tiny wire the size of a hair. I could ride on it a couple of miles, but couldn't make it to work. I had to keep the tire/tube aligned, find the hole in the tube, and then find the matching part of the tire. Took me about a month to find it. Even when I knew where it was it was hard to find. It always found the tube though!

I'm in my 3rd year of full time commuting. I think that I've had five flats...so, math says >1. Now that I have Schwalbe Marathon Plus on my main commuter, the # of flats = zero. But on my other road bikes with thinner, more supple tires, flats do happen occasionally. Meh. The last one might have been back in the early Spring or so. It's now a distant memory.

Not saying that you don't repair tubes but this alone is a good reason to repair flats. How are your going to find that offending piece of glass if you just replace the tube? We recently got a donation of about a dozen tubes from one person at my local co-op. All of them had a puncture in the same spot...on the inside of the tube:foo: If the guy had repaired the tube, he might have found the problem before blowing roughly $70.

I usually replace the tube since they usually last me so long, this was a longer and more frustrating than usual experience for me with the glass being hidden in the tire. I now know about using a poking tool to look for those pieces, as well as have a newer tire with flat protection.

My worst flats were from a broken wire in the sidewall of a tire that hid back inside the rubber when I was looking for it. I didn't know some tires had wires in the sidewall! Went through all three of my spare tubes that day and had to patch one tube on the side of the road when I finally found that sucker. Luckily I had a spare tire, and somebody had an almost full garbage can within 25 yards to dump the old tire in.


Second worse was a transverse cut in the tire, about 1/4" long. After a couple of flats in the same place (with nothing in the tire like glass shard or wire) I finally figured it out. The tire was flexing enough while rolling that the cut was basically chewing the tube until it chewed a hole in it. IIRC I put one patch on the tube, and another on the inside of the tire, and rode the tire until it was worn out (the rest of the way).

Bike 1: (700x35c) a flat caused by rim tape tear. Bike was 3+ years old.

Bike 2: (700x38c) a flat caused by tiny glass embedded in the tire. Also 3+ years old.

Bike 3: (700x30) Flat caused by a 5mm cut in the outer tire just last week, new and better bike only 9 months old. :(

That's all I have to report. :)

I don't get any in Japan because people don't throw trash on the ground, much less break bottles anywhere and every where. Also, the street crew sweeps the bike lanes regularly.

With that said, on a trip to the US I did see a pickup truck driving slowly with a guy hanging off the side using a leaf blower to clear the lane.

"Do you ever get flats?" Hahahahaha! Hahaha! Hahahahhahahahhahahahaha! Hahahahahhahaaha!

Dude, I commute through the Broken Glass Capital Of The World (Oakland, CA). Flats are a fact of life. Getting a flat in the wrong place at the wrong time could alter the course of your LIFE. No joke.

I do about 5-6k mi/year and have managed to get it down to about one flat per year, which if you ask around is pretty damned incredible. But, now that you've asked I'm sure I'll be dealing with one on the ride home today.

My secret(s)... Armadillos. Specialized Armadillo Infinity tires. 38's on the rear, 35's on the front, running low PSI for comfort and flat prevention. Specialized AirLock tubes inside. Imported B&M dynamo powered headlight to see - and avoid - running over as much debris as possible. And a great big dose of LUCK.

I'm always open to suggestions, but this setup has proven to be the best combo of cost/weight/performance/wear that I can find. IMO, pinchflats are inexcusable. I'll give a free pass to anyone on their first, but after that the shame is on you. Pinchflats = lazy/dumb rider.


-Kedosto

did a 9 month bike tour with out a flat tire.. :thumb:

Kedosto – interesting info. What PSI do you use? Sounds like you have a good solution that works for ya. I’ve never had a problem with flats, so it is interesting to see your perspective.

As for pinch flats, I don’t think anyone here gets them commuting. No forgiveness required. Commuters are not a lazy bunch.

What is an airlock tube?

I run 45fr/75rr. I run a larger size on the rear specifically for the lower psi I can run.

AirLock tubes are Specialized brand pre-filled with their sealant. The sealant they use is very long lasting and effective.


-Kedosto

Since 2014, I've had 7 flats.
2014 and 2015 were flat-free years.
2016, I had one due to operator error (hit railroad tracks, hard, with road tires.) I also blew 2 due to old tires.
2017: One due to giant nail (obscured by roadside sand in late winter), 3 on the same stretch of highway, on two different group rides, due to tire wires. It was fun pretending to run a "fix a flat" clinic :rolleyes:

That's still quite a pressure differential. Do you carry a big load on the rear? Just curious. :)

Maybe one flat per 2000 mi ridden? Estimate 2/3 due to wire (from steel belted car/truck tires?), 1/3 due to glass. Glass is usually easier to see, those wires are invisible.

There are a few things you can do to somewhat reduce the risk of a flat: keep an eye out for glass (looking down the road far enough so you can plan evasive maneuvers), avoid riding through the "debris triangles" in intersections; avoid riding through piled up sand/dirt (glass and those little pieces of wire get washed off the road and trapped there, waiting to pounce), absorb bumps with your legs/hands (though I've only had one pinch flat), once you've located the hole in the tube, look carefully for the cause in the tire and don't believe that it fell out - keep looking, be gentle with your tube valves, etc.

I get somewhat fewer flats now than I did as a newbie, but they still happen.

---------

I've been using a spreadsheet to keep track of my flats for about 8 years now. Before I started tracking my working theories were:

1) Most flats happen on the rear tire
2) Most flats happen when the roads are wet
3) Most flats happen on tires that I've used for over 2000 miles
4) Most flats happen when I've been riding on roads with bike lanes

The rear tire theory has proven true (36 of 42 flats have been in the rear, and three of the others were tube or tire failures, not puctures).

The bike lane theory also seems to be correct. About a third of my flats have been slow leaks that I found either in the morning or at the end of the day without having had any idea when the puncture occurred. Commuting typically accounts for about two-thirds of my mileage and there is no way to avoid bike lanes entirely on my commute. The vast of my flats that weren't slow leaks have happened on a road with a bike lane. I've only had a couple of flats on recreational rides, even though I use less puncture resistant tires for that purpose.

The wet road theory has me kind of puzzled. It's demonstrably true that objects will penetrate wet rubber easier than dry rubber, but only about a third of my flats have occurred on wet roads. Looking at the details of my log, I'm tempted to form theories to explain this away, but the data seems to be telling me that I'm just as likely to get a flat when the roads are dry.

The mileage theory is harder to evaluate. I've gotten 18 flats on tires with fewer than 1000 miles, 14 flats on tires between 1000 and 2000 miles, and 11 flats on tires with over 2000 miles. On the other hand, the flats clearly start to group together when the mileage gets high. I have more total accumulated mileage at the lower numbers (I have a lot of bikes, so a lot of tires that haven't hit 1000 miles). Once flats start to seem frequent (about three flats within 500 miles) I tend to give up on a tire.

I had three flats in one day in 2014. That was when I stopped using GP4000 tires and stopped riding my road bike until I got some Gatorskins. It has not had a single flat since. That frame will only fit 23s or narrower.

I had one flat on a rear tire on my touring bike in 2015. The tire is a Marathon Supreme 26x1.6. I believe a piece of glass cut the rear tire and punctured the tube. Tire was repaired with Shoe Goo and has gone another 1000+ miles.

I don't ride as much as many here, perhaps 2,000 miles since 2015 but I might be underestimating.

Exactomundo :-)

2 flats in less than a week this year (made me change to SCHWALBE Marathon Plus).

Well actually my front is usually closer to 50psi and I do roll quite heavy. I typically start my week with a pressure check and inflation on Sunday night or Monday morning. I over inflate and leak down to hit my sweet spot about Wed/Thurs then run under inflated Thurs/Fri.

Actual rolling psi is probably more like 48-ish front and 70-ish rear on 35fr/38rr tires. I'm about 235lbs (ride ready) and can easily reach 290-300lbs total rolling weight (me, bike, panniers, cargo) with most of the weight on the rear. I've never checked, but I wouldn't be surprised of it was a 35/65% weight split.


-Kedosto

For those who get flats from goathead thorns, glass shards, and other small, sharp objects, I wonder how effective it is to check for "intrusions" on the inside of of the the tire, by running one's fingers around.

Even if you don't see a protrusion on the outside, a piece of glass that has worked its way into a sipe, or a thorn that has been worn smooth on the outside, may still cause a puncture from constant rubbing on the innertube. Since I started using tire liners a few years ago I still feel around the inside of the tire out of habit.

And since I've been using Mr. Tuffy's Tire Liners I went from one or two flats a month to one or two a year, mostly nails and metal shards.

Always check the inside of the tire before replacing the tube! Be careful about it, as running your fingers around in an effort to detect sharp objects might prove to be successful in a painful way.

AirLock tubes won't save you if you don't remove the foreign object from the tire.


-Kedosto

Last year, no flats with Marathon Plus on my 1991 mountain bike in about 4 000 km. This year got two flats in less than a month (including a side cut that killed that tire) in the Spring with Grand Prix 4000S II tires on my 2012 Giant TCX bike. I then added Mr. Tuffy liners and no flat in the following 3 000 km. Now that we're in the Fall season, I replaced the GP with Marathon Plus on my TCX hoping to reduce my chances of having a flat in cold weather.

No flats on my commuting bike(s) for two years. Now on a run of four in three weeks. :(

EDIT: Now 5! Realised that the tyres are full of tiny (2-3mm) chunks of glass, and the tyre tread is sufficiently worn that the small chunks are getting worked through the inside of the carcass. Ordered up some Continental puncture resistant tyres - hopefully that will put an end to it.