By that I mean the liners that are inserted between the tube and thread of the tire.. Seems flats come in spurts.. maybe 6 months with none and then 6 in one month.. Last string of flats , I inserted the brand " Stop Flats 2," for 28 mm road tires. I've seen no difference.. I've had two flats within in the 2 weeks.. Each flat is a small pin hole leak facing outwards towards the tire liner..
My question. .Maybe where the ends of the liner meet, maybe that is a cause of friction. ?
Who votes they help or hurt.. Thanks.

I knew a guy from Arizona who swore by his Mr. Tuffys, but I've never used them. Not too many cacti around here.

I run Mr. Tuffies and rarely get flats. Did you cut yours to size? If so try sanding down the cut edge.

I thought about that Puppets. But , the instructions say don't cut to size.. Since their advertisement claims the surface facing the tube is a soft pliable material, I'd not thought sanding down the edges to be necessary.. Stop Flats 2 says if you get a flat they owe you a tube. As of today, they owe me two tubes . .. Both small pinhole leaks facing outward.

Used properly tire liners should prevent flats caused by simple punctures or (out west) thorns. OTOH they won't prevent all flats, and if improperly installed can cause flats because of chaffing on the tube against the edge of the liner.

Overall most folks say they help, but if you don't feel they're helping you, take the out.

Yes, they help. I use a second inner tube to line the tire before the prime inner tube, but I play in the mud and bushes, not the pavement.

Well, tyre-liners do nothing to reduce the amount of flat-causing objects out there; glass, thorns, nails, etc. So installing liners will not change the odds of you running over one of these things. However, it does buy you time in penetration resistance. It's very, very rare that you get punctured right away. But it takes numerous revolutions after picking up the object in your tyre for it to work its way through.

Tyre-liners will increase the penetration distance needed to reach the tube and buy you more time. IF you're the type that hears the tell-tale >click< or >clip< noise of running over glass or thorns. Then you can reach down and rub your tyre to scrape off the debris. The tyre-liner will give you more time and distance to perform this task, say up from 100ft to 500ft or 5 to 30 seconds.

However, IF you're the type that never scrapes debris off your tyre, then having liners will not help by much as the stuff will eventually penetrate anyway.

^^Most of the stuff that I get flats from an my road bike is really small stuff. Small enough in fact that when I have run tire liners the extra thickness has stopped almost everything. I stopped running them because I don't get flats too often anyways and because I didn't like the way the bike felt when I was running them.

If the object doesn't cause a flat at first penetration it won't cause one. Try driving a wedge into a steel gap. It goes in so far and then bounces. Same thing with a rubber tire. https://draco.acs.uci.edu/rbfaq/FAQ/8b.15.html

When I was still working at a local bike shop I stopped counting how many cyclists came in to have a flat repaired -- and surprise, surprise -- there was a tire liner inside the tire.

Tire liners work great. They are very very difficult to penetrate.

I use a first line-of-defense approach. If I have a Vectran, or Kevlar, belt on my tire - and the object penetrates that - I believe it will make mince-meat out of a Mr. Tuffy or such. I very rarely get flats. And my tires/tubes don't weigh a country-ton.

How does a rubber tyre compare to a steel gap?

How many goathead thorns have you pulled out of a tyre? They are pretty much always the thorn only with the head part worn away. It takes many, many revolutions of the tyre to repeatedly press the thorn deeper and deeper into the tyre. Many times, this results in a slow leak later that's not easily detected. Often times, the rider will replace the tube and end up with another slow leak. That's because the thorn has worked it's through the casing and the outsid end is shaved down to the level of the tyre surface, making it hard to detect.

Jobst isn't the end-all of bike-knowledge as his abstract academic background is often at odds with in-the-field experience of Sheldon Brown and others with tonnes of shop time. Over 10 years ago, right after that post, I devised a test verify his assertion on wiping tyres. Even when presented with all the experimental data, he refused to accept it. My test went roughly like this.

1. toss 100 goatheads onto the ground (about 2 handfuls). They land in roughly a 5-ft diameter circle
2. ride a bike at 20mph through the goatheads
3. continue riding for another 12miles (I chose this distance because it was the distance from the shop to my house).
4. repeat 10x (number of same rides in a week to work and back)
5. count number of goathead spines left in tyres
6. count number of flats.
7. change a variable and repeat.

The results were as follows:

1. the tyres pick up 3-5 goatheads when running through the thorn-field, regardless of liner
2. Without liners = 2 flats immediately, 5 flats within 5-miles, 3 flats in 6-12 miles, 100% flat rate
3. with liners = 1 flat immediately, 3 flats within 5-miles, 4 in 6-12 miles, 80% flat rate
4. with liners + scraping = 1 flat within 5-miles, 2 flats in 6-12 miles, 30% flat rate

This test is easily repeatable by anyone with similar results. Most goatheads never puncture right away. Most of the time, you'll never even notice when you ran one over and by the time you get a flat or slow-leak, only the spiny thorn is left in the tyre. Liners do reduce rates of flats given the same odds of running over debris. Liners along with scraping reduces flats even further.

I have another experiment on scraping alone somewhere... Although now with advent of digital video, I should revisit this with video-analysis of the scraping action.


I agree with Panther007, tyres with built-in kevlar liners are even better. Although for the ultimate commuter wheels, I like to install Tuffy liners inside kevlar-belted tyres along with thorn-resistant tubes and Slime. I rode all the way across the US in '96 and got 2 flats. But boy, those tyres were way slower than my racing tubies.

I'm sure they help. Looking at a liner that has been in a tire for a while will show quite a few little bumps, that are the ground up remains of goathead thorns that never made it to the tube.

I love it: so, if the liner doesn't get it, then the kevlar will, and if the kevlar doesn't get it then the thorn-resistant tube will, and even if the damn thorn gets through that, the Slime will stop the leak!!! LOL

He didn't say so, but DannoXYZ wears both a belt and suspenders to hold up his elastic-waist cycling shorts.

I've got 5000 miles on Schwalbe Marathons with Mr. Tuffy's and thorn resistant tubes. No flats. Nearly all commuting miles (think lots of road debris: broken glass, wood, metal slivers from tire casings, etc.). Of note: no goatheads around the Pacific Northwest.