how do people pinch flat on road bikes?

[mtechnica]

I've been struggling to understand how this is such an issue as I hear people talk about it online all the time. I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

[Likes2ridefar]

hit a pothole descending at 40mph

[thegunner]

underinflate, hit some sort of debris in road, pinch flat?

[chiasticon]

ride in a group, have someone not call out a pothole, hit it dead on, boom. i'm around the same weight as you (sometimes less) and i've gotten pinch flats with 100+ psi using this method.

[seanile]

easy, weigh 200+ and find yourself riding on <90psi

[BumbleBeeDave]

hit a pothole descending at 40mph

. . . and I've had it happen to me and stopped to help a buddy after it happened to him.

BBD

[BobO]

Unseated manhole cover will pinch flat you in a hurry. Also, those 3D reflectors on some roads look like a good way to do it, though I haven't hit one yet.

[oliver1850]

I weigh under 150, generally run 100+ PSI on anything under a 28. I can usually manage to hit the lone rock on a piece of smooth pavement and pinch flat.

[sitzmark]

I've been struggling to understand how this is such an issue as I hear people talk about it online all the time. I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

Shhhhsh - don't jinx yourself. :)

[JStonebarger]

Usually it requires a butyl tube. Much harder with latex. (This, btw, is probably the real reason tubulars flat less than clinchers.)

[FlashUNC]

http://geoawesomeness.com/wp-content/uploads/2013/10/lidar1.jpg

[martinez]

I've pinch flatted a bunch of times. On continental gp4s and panaracer paselas 25cc at 90-100 psi.
And I usually ride specialized or bontrager tubes.
Streets around me aren't extremely terrible, but I assume if you're riding fast enough at a certain point in the street and at the right angle than you are susceptible to pinch flats.
You must have nice roads

[zap]

…now that you posted……..

[wallymann]

ride in a group, have someone not call out a pothole, hit it dead on, boom. i'm around the same weight as you (sometimes less) and i've gotten pinch flats with 100+ psi using this method.

this. have dented rims this way too, and i top my stuff off at 8-bar before every ride!

I've been struggling to understand how this is such an issue as I hear people talk about it online all the time. I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

you must ride very carefully. try riding with a really fast group full of cat-2s AKA the wednesday-night-worlds on those same rough roads.

and fwiw...155# *is* pretty dang light in these parts!

[Vientomas]

I've been struggling to understand how this is such an issue as I hear people talk about it online all the time. I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

You have been lucky.

[rwerkudara]

similar to previous postings. under inflated tires, hit a pothole or debris on the road (especially wet roads), pinchflat...

[mtechnica]

Hmm a pot hole at 40 would do it, I guess I've avoided that so far on a road bike. The last time I hit a pot hole at that speed I blew a spoke on my touring bike.

[Dead Man]

In all the potholes and expansion gaps and crap I've hit, sometimes pretty damn hard, I've somehow never pinch-flatted, all on it's own. I have pinch flatted on these things after getting a minor puncture/slow leak that had my pressure drop to pinch-flat danger level, though.

I did, however, experience my first ever pinch-flat only flat last Septemberish. I never even saw what it was I hit, but I was mashing along the highway solo, face between my legs, force-breathing, and BAM clatter clatter clank! I turned back to see what it was, but couldn't see anything, so I guess I must have sent it off the road. Really glad it didn't end up in my front fork. That's what you get for riding blind I guess..

I made it about .5km and felt my ride smooth out in that tell-tale way.... wah, waaaaah.

I've since gone to to tubulars 100%.. Have only flatted once, and it must have been a doosey, because it left a 1cm gash in my tire.

[Seramount]

I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

sheer luck.

hit enough stuff and your day will come.

[JStonebarger]

I ride some pretty crappy roads, including gravel. And I race 'cross on clinchers. While it's possible to flat latex tubes (pros do all the time, even in tubulars), it's not nearly as easy. With 23mm road tires I ride at 105-110psi, with 32mm 'cross tires I ride at 40-45psi for gravel, 18-26psi for 'cross. I'm 180lbs, and I don't use sealant.

Years ago at the Fitchburg/Longsjo road race I was coasting down a slight hill in a big masters pack, momentarily sat up to grab something out of my jersey, and squarely hit the one small pothole on the whole 11 mile loop. This resulted in two broken rims (Velocity DeepV), but oddly enough only one flat latex tube...

Latex.

[Fatty]

Just curious , what do you consider bad roads?
Springtime in Chicago, cars and trucks tear up sidewalls and break rims. Poor little bike tires don't stand a chance.

[Mark McM]

I've been struggling to understand how this is such an issue as I hear people talk about it online all the time. I've never pinch flatted, and I ride a lot of miles on bad roads. I even run 23c tires as low as 80psi and sometimes it drops under that. No pinch flats. I'm not extraordinarily light either at 155. What gives?

Well, road condition is relative - one person's "bad roads" may be another person's "normal roads". Also, some people ride "lighter" than others (they aren't actually lighter of course, but their positions and/or riding styles help them absorb road irregularities with less shock force). Some riders find themselves in situations where it is more difficult to avoid running over potholes or other pinch-flatting obstructions (say, in tight packs where they can't see the road ahead, or at times of poor visibility like night-time or in the rain). In any case, pinch flatting is very real issue for some people in some situations.

[macaroon]

So far this winter, I've managed to write off four tyres, a rim and god knows how many innertubes. I tend to do it hitting potholes or stones at night.

[F150]

I'm 210#, ride Panaracer Paselas (27x1 1/4 or 700c x 28) as low as 65 psi rear/60 psi front, normally 80/75, never once a pinch flat (knock on wood). If any of those pictured in Flash's photo have a sharp edge, and you just squared one up and failed to flex your knees or elbows at all, I can see a flat. Can also see a clean line on the right shoulder.

Also don't run 18c-23c tubes in 28c or 32c tires.

[saab2000]

Riders who pinch flat a lot ride 'heavy' and don't unload their mass over rough surfaces. Learn how to let the bike dance beneath you and it will happen much less.

[aramis]

Usually it requires a butyl tube. Much harder with latex. (This, btw, is probably the real reason tubulars flat less than clinchers.)

Man I used to pinch flat a lot with butyl tubes. Since I can get latex tubes from the uk for not much more I've been so happy, and pinch flat freed.