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Are you talking about the 22mm, or the 25mm Sprinter.....Unless you are over 100 Kilo, there is no reason to go over 100 psi on the 22mm rear tire. For the 25mm one, 90 to 95 should do it.
I haven't bought one in 10 years, because about that time, their quality went down the toilet, and they started to get "lumpy" after mounting. I guess that they would still be good enough if you were really "old school" and wanted to train on them.
 

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Discussion Starter #22
The ones I just bought are the 25c Gatorskin setups. I realize they have mixed reviews and I will report back on how they perform.

I will say that out of the box their manufacture quality seems much better than the 22c Sprinters that I raced on. They seem incredibly straight on my stretching rims and I don’t foresee a problem gluing them on. I’m also going to try 30ml of Conti Revo sealant as a preventative. I still won’t mind carrying 2 spares anyway, but let’s see how the Revo performs hoping to not have to rip off a tire.
 

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Banned Sock Puppet
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I've seen them pinch flat on the road. At 80-90psi. 25psi for cx? That's kind high, most ride in the high teens.
High teens, really? Wow. I know people who run mountain bike tires in the teens, but cx tires? What size tires are those?
 

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'brifter' is f'ing stupid
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33mm per UCI regs. I know KfC has been down around 15psi lots of times, she weighs around 140.
 

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One thing I always wonder about, what role does too high a psi play in "squaring off" the tire tread? I guess for all tires, clincher and sewup. In other words, if I have been running 120psi on a 25c clincher whereas for comfort I probably should have been running 90psi, is my mistake causing premature flat spotting the tires? For anyone who has lowered their pressures, do you notice the tires lasting longer?
Higher pressures reduce the size of the contact patch and therefore increase the force per unit area. Tires wear out (lose tread rubber) by the scrubbing action of the power transfer from the rear wheel to the road, so a smaller contact patch narrows the "wear zone" and speeds tire wear. The net result of higher pressures is faster tire wear on the rear. Note that since there is essentially no power transfer on the front (except from braking) front tires essentially don't wear out from losing tread rubber. I once weighed a front tire after 6,000 miles and it had lost no weight. In that same distance I wore out two rear tires.
 

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Higher pressures reduce the size of the contact patch and therefore increase the force per unit area. Tires wear out (lose tread rubber) by the scrubbing action of the power transfer from the rear wheel to the road, so a smaller contact patch narrows the "wear zone" and speeds tire wear. The net result of higher pressures is faster tire wear on the rear.
This makes sense. I know higher pressures feel like they speed the wear on my vertibrae.
 

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Discussion Starter #27
Higher pressures reduce the size of the contact patch and therefore increase the force per unit area. Tires wear out (lose tread rubber) by the scrubbing action of the power transfer from the rear wheel to the road, so a smaller contact patch narrows the "wear zone" and speeds tire wear. The net result of higher pressures is faster tire wear on the rear. Note that since there is essentially no power transfer on the front (except from braking) front tires essentially don't wear out from losing tread rubber. I once weighed a front tire after 6,000 miles and it had lost no weight. In that same distance I wore out two rear tires.
That explanation makes a lot of sense. Thanks.

Makes me wonder though why many move their front tire to the rear and put a new tire on the front, when it really makes more sense to just replace the rear. At least so when the front is still good for cornering and braking.
 

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Because you want the best/newest/least damaged tire on the front. It really depends on how many nicks and cuts you get in your tires I guess. I'll keep putting the new tire on the front.
 

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Because you want the best/newest/least damaged tire on the front. It really depends on how many nicks and cuts you get in your tires I guess. I'll keep putting the new tire on the front.
^^^This^^^
 

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Because you want the best/newest/least damaged tire on the front. It really depends on how many nicks and cuts you get in your tires I guess. I'll keep putting the new tire on the front.
In addition to that key point, while front tires don't wear out, they do age. They craze and crack, get cut, and the rubber eventually gets brittle and crumbly. Not a place where I want to be. There are many practices that experienced riders have adopted for good reason, and moving the front to the rear and putting new rubber on the front is a good one.
 

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Discussion Starter #32
I realize this procedure as a best acceptable practice, however, you confused me when you provided and example of 6000 miles on a front tire coupled with wearing out 2 rear tires.
 

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I realize this procedure as a best acceptable practice, however, you confused me when you provided and example of 6000 miles on a front tire coupled with wearing out 2 rear tires.
Other than cuts the the things he's talking about that make front tires go south are caused mostly by the passage of time not mileage. 6000 miles isn't a ton of time for a lot of road cyclists.
That being said if you're taking the time to replace one tire why not take an extra 5 min. and rotate. Although I say that from the perspective of someone who only uses clinchers and this thread is about tubulars so perhaps not.
 

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......
That being said if you're taking the time to replace one tire why not take an extra 5 min. and rotate. ...
Five minutes to rotate a tubular??? Maybe 1 hour, if you're lucky! Also, any time you remove a tubular, you risk separating the base tape from the carcass, adding another hour or 2 to the time. Re-set tubulars also just plain look awful. TBH, I know of NOBODY who rotates tubulars, at least not as a regular event.
 

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Five minutes to rotate a tubular??? Maybe 1 hour, if you're lucky! Also, any time you remove a tubular, you risk separating the base tape from the carcass, adding another hour or 2 to the time. Re-set tubulars also just plain look awful. TBH, I know of NOBODY who rotates tubulars, at least not as a regular event.
WTF. Did you stop reading or just ignore my last sentence? Or just decided to argue with a point no one made anyway.
 

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Discussion Starter #36 (Edited)
I think everyone means well and the input is appreciated. Sometimes it is just difficult to remember what type of tire we are speaking of and when we start comparing pressures for tubulars and clinchers it is easy to forget where we are.
 

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I realize this procedure as a best acceptable practice, however, you confused me when you provided and example of 6000 miles on a front tire coupled with wearing out 2 rear tires.
At the time I was doing a bunch of research on tire wear and was having folks send me their "worn out" rear tires so I could take measurements. I soon realized that what people thought were worn out tires still had lots of miles in them, so I put them on the back wheel, one after another to see how many additional miles I could get out of them. As a result, the front tire stayed there for 2/3 of my season, thus the 6,000 miles.
 

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I'm late to the party, but good questions on tubs!
Here's my experience/comments on them (on the road):

1. at "equal size" (see point #2 below) and psi, the tubs always ride smoother than clinchers. Always. Even a crappy tub will ride almost as smooth as the best clinchers out there. I'm guessing the reason is with tubs, the contact area between rim and tire is much greater than the contact area between rim and tire in a clincher. With tubs, the rim is riding on top of a self-sealed rubber cyclinder, whereas in clinchers the rim is not riding on top of the tire instead the rim is riding only on the tire bead (which has smaller surface area for shock distribution). Hope I made sense.
2. tub sizing always run a tad smaller than clinchers, i.e, a 25mm tub is actually 25mm wide when pumped up regardless of rim wide, but a 25mm clincher will have varying degrees of widths depends on rim width and even bead-hook profile (ie, hook vs hookless). So in practice, a 25mm tub is not as wide as a 25mm clincher when pumped up. And because of this, you'd need to run the 25mm tub at a slighter higher pressure than a 25mm clincher if you want to keep "everything equaled".
3. Tubs indeed can "pinch flat", but method of "pinch flat" is not the same between tubs vs clinchers. With clinchers, an inner tube can be pinched at the interface between rim-hook and tire-bead if you hit an object hard enough, especially at lower psi. This is the mechanism of pinch flatting in tradition clincher. With tub, there is no such rim-tire interface, so technically there is no pinch flat. So then how does tub "pinch flat"? This I'm not sure, but I've "pinch flatted" a tub once in my life when I ran over a metal object with a sharp edge on the road at high speed. It was an instant flat with a loud pop. I thought the tire was completely ripped. Yet when I examined the tire, there was no rip or any hole in the tire! Then when I got home and unravel the tub (by cutting the thread) to check the inner tube (latex) and there was indeed a hole there, but no hole at the same section of tire! So, I could only conclude that the "pinch flat" is due to the metal object poking deep enough AND fast enough into the carcass of the tire to cause the inner tube to blow up while NOT poking a hole into the carcass. Anyway, I was able to patch the latex inner tube and sew back the tire using nylon polyester thread! My sewing was not perfect because afterward, there was a slight wobble on the tire but that did not affect how the tire ride on the road so I kept using the tire until it was time to replace it due to wear.
4. at extremely low psi, a tub can peel off if you take a corner while bumping into an object, so glueing is important with tubs if you're a bigger rider. So if you run low psi with tubs, gotta make sure you glue them well. With clinchers this is not an issue, that's because you'll pinch flat before the tire will ever have a chance to "roll off".
5. when it comes to sprinting for the line, nothing beats a tub pumped to high psi. The sprint just feels snappy. With clinchers, especially like a 28mm at <70 psi, sprinting is like running in mud because the tire gives too much. Climbing out of the saddle also feels like mud. I've ridden 28mm clinchers at 70 psi ONCE in my life, and i'm light at 125 lbs, and I do not ever want to do that again. It's just toooo smushy for "spirited riding", because multiple out-of-saddle accelerations out of almost every corner will take a toll on your legs as you hang on for dear life trying to keep up with the peloton. Over rough pavement, it's a different story. But anyone who says wider and lower psi gives you less rolling resistance (in a STEADY STATE test) probalby hasn't done much hard accelerations out of corner trying to hang on to dear life, because if they did, they would understand that rolling resistance will mean sh8t if you get dropped due to having to keep burning matches because your tires are smushy. Different horses for different courses, I guess.
6. about tire wear, especially the rear. I have always found that with both clinchers and tubs, the lower the psi, the faster the tire will square off. This is especially true if you're the type of rider that do a lot of out of the saddle efforts where the rear tire is experiencing a lot of tire deformation. And i'm that type of rider. Because of this, I tend to square off the rear tire pretty quickly even for a light weight person. You know, it's a little annoying when you see an expensive tire being squared off in the middle while the rest of the tire seem almost new!
 
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