88ss

Hit a sharp rock with the rear wheel and got a pinch flat with Pirelli TPU inner tube under my new Gp5000. Two tiny pin-prick looking punctures. I used a regular everyday tube kit made for regular everyday tubes. I did not follow the directions though, I did not rough up the area of the punctures, just cleaned it with 90+% rubbing alcohol then put the patch glue on, when the glue tacked up I put the patch on and rubbed it in with a smooth plastic tire-iron. The gp5000 had damage on it's sidewall, not good I thought. I cleaned it with rubbing alcohol, then cut a small patch big enough to cover the damage from the sidewall of a good quality road tire with scissors and cleaned it with the alcohol too. Then I made sure the damage on the sidewall was saturated with "super-glue" and stuck the patch over it. Since then I have done over forty miles over two days without having to put any air in the tire, running over sketchy paved streets, debris, a few fast downhills at over 30mph, and 25 of the miles were done on the level at 21-22mph. The patch on the sidewall is still where I put it and apparently the tube is happy too.

veganbikes

An odd username hopefully not related to anything bad. Anywho pinch flats are an easy fix, PUMP YOUR TIRES! Seriously pump your tires. You shouldn't be pinching unless you aren't running enough pressure in your tubes.

Glad it is working for you that is good luck. I haven't been totally sold on TPU except for a lightweight spare but I have very few issues with good quality butyl tubes and proper inflation.


Everybody just please pump your tires and don't come into the shop with one really low tire and one flat tire and tell me you pump your tires regularly and you ride daily I had someone come in today saying that they had just pumped their tires last week after 10 seconds of "Uhhhhhhhh" before the answer (to the question when was the last time you pumped your tires) and also saying that their 30 year old bottom end plastic shifter was working fine when it probably hadn't shifted in 10 years it was gummed up and even with plenty of degreasing and triflow it barely made a move. The front shifter started to work after a little bit but they said that was the bad one. People are crazy.

88ss

rm -rf

Correct inflation won't save you at 30 mph downhill, hitting a 3/4 inch squared off gravel chunk. As I found out. The only rock on a perfectly smooth road too.
Dropping a wheel into a slotted sewer cover at 8 or 9 mph will instantly pinch flat and additionally bend the rim. The covers went curb to curb all the way across the road. Grrr.

Superglue
I've never had any luck with superglue for tires. It's too inflexible, and pulls loose.

Fredo76

Had a flat on my first use of a TPU tube today, in a 28mm Specialized Turbo Cotton. It was a slow leak though, only noticed after my ride, and was the easiest tube I've fixed in awhile. Park Tool sticky patch, which seemed like a good match to the tube. So far, so good. The thorn was less than an eighth of an inch long, like maybe 3/32". The street that I weeded so carefully in the fall of 2020, filling several garbage bags with goathead plants, aka 'Puncture Vine', was gone over with a weed-eater by a neighbor being helpful, he thought, before I could get to them this fall, the first year they came back noticeably. Several flats lately, probably all incurred on my short little street. Orange Seal, eh?

chaadster

One of the things I most like about TPU generally is that it’s highly resistant to sudden, catastrophic deflation. In addition to being puncture resistant, it’s hard to tear, so punctures and cuts don’t rip open, and so stay small and leak slowly.

I don’t know how that happens, but I guess the tube elongates under pressure but without tension in the tube wall, so it doesn’t act to pull the edges away from the puncture site. Dunno.

88ss

A rider's weight has a lot to do with it too I think. I ride big frames as I am a big person and weigh over 200 pounds. Some of the guys I ride with look like they may weigh half of what I do. I am sure because of this it is harder on my bike and tires, I suspect it is an exponential thing, where with weight and speed the chance of some failure increases at a square or cube etc.. I have hit square-edged potholes and other obstacles which others in the same group or paceline have hit and yes have broken tires/rims where they have not. I am very conscious about tire inflation and it's effect on reliability and rolling resistance too, as I am an older rider I need all the speed I can get to keep up with the group or just make it easier on myself.

Rick_D

Alternately, if you strike something significant at speed with butt well-planted on the saddle, you can snake-bite most any road tire/tyre pumped to spec, especially narrow ones.

88ss

Yea, mine are the 25mm wide jobs. I know wider tires are more in style now, but that is the width that was on the bike so I just ordered the same size. Continental does say that a 28mm on the rear and 25mm on the front is the fastest combination, so maybe when the rear dies someday I will replace it with a fatter one.