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Discussion Starter · #1 ·
I just had two pinch flats in two weeks, one while riding on the trails and one on the road. (I actually don't know how I got one on the road.) I run on 30-something psi cause I run on tubes and I don't really know how to prevent getting pinch flats, even though I'm doing my best preventing them. I can't be my spokes cause my rim tape's still in good condition. The rims? Well I'm running a 23mm rim on a 2.2 Ardent Race (rear) and a 2.25 Ardent on the front. But both of those pinch flats were on the rear. I heard talcum powder works but they didn't told me how it works?? I don't know. Any suggestions?
 

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In a pinch flat event, talcum powder helps the tube slide out of the way of the rim rather than grip it and get cut. Not a huge help, but better than running the tube clean and grippy.

In the old days before tubeless was invented, pinch flatting was a huge concern in DH racing. We used to take an old tube, cut out the valve, and split the tube all the way around along the outside diameter, and use it to "sleeve" the good tube on its inner diameter, where the pinch flat/snakebite cuts occur. You could cut away more of the sleeve tube if you wanted, to reduce weight, but I usually just left the whole thing intact, and used a little bit of electrical tape to secure it to the good tube before installing it in the wheel. It added weight, of course, but definitely helped reduce pinch flats because the dummy layer could take some of the abuse before the inflated layer.

Ultimately, though, tubeless is the way to go. I haven't had a flat for three years, and I ride A LOT.
 

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Elitest thrill junkie
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More pressure.

Contrary to hype, if you are pinching the tube, you are probably close to pinching the tire, something that does happen with tubeless too, and that becomes a very hard puncture to seal with tubeless. It's happened to me more than once. Wider rims allow for lower pressure (a bit) with more sidewall support. Higher volume tires allow for lower pressure. Stiffer sidewalls allow for less pressure. On vacation last week with maxxis DD casing tires, I was able to use a lot less pressure than my normal with EXO (thinner casing). Tubeless inserts (cushcore) allow for less pressure. Tubeless itself IME doesn't really allow for less pressure, it stops a tube pinch, because the tube isn't there, but if you are pinching the tube you are just a hair away from pinching the tire, so the problem is still there.
 

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The easy answer is higher pressure.
It may be related to technique, I suppose. If you tend to sit on your saddle through the rough stuff, rather than standing up and absorbing with your legs, you'd be more likely to pinch flat.
 

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Discussion Starter · #12 ·
In a pinch flat event, talcum powder helps the tube slide out of the way of the rim rather than grip it and get cut. Not a huge help, but better than running the tube clean and grippy.

In the old days before tubeless was invented, pinch flatting was a huge concern in DH racing. We used to take an old tube, cut out the valve, and split the tube all the way around along the outside diameter, and use it to "sleeve" the good tube on its inner diameter, where the pinch flat/snakebite cuts occur. You could cut away more of the sleeve tube if you wanted, to reduce weight, but I usually just left the whole thing intact, and used a little bit of electrical tape to secure it to the good tube before installing it in the wheel. It added weight, of course, but definitely helped reduce pinch flats because the dummy layer could take some of the abuse before the inflated layer.

Ultimately, though, tubeless is the way to go. I haven't had a flat for three years, and I ride A LOT.
Cheers for the suggestion. Well I am looking forward on buying tubeless ready rims when I get the money. But while I still have tubes I'm looking for a solution on trying to regret flats while shredding on the trail. Yeah I usually like it fast but that's also the reason for my flats. I only got two flats on the trail, others could be on the road. I might as well clean my tube and rims before I get my tube vulcanized and ready to go.
 

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Cycologist
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If you're getting flats on the road at 30psi, I really doubt they are pinch flats, unless you're really ramming into curbs or something. Are you feeling the rim itself hit? If you are, you need to run a higher pressure.
 

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Before you put a new tube in, besure there are no thorns, cactus needles, nails or whatever protruding through the casing inside the tire. I've seen people get a flat... change the tube... and it's flat right away because of what causes the original puncture. There are a lot of cacti here where I ride and my tires probably look like a pin cushion inside.

More pressure is your solution for now though until you go tubeless.
 

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Discussion Starter · #15 ·
If you're getting flats on the road at 30psi, I really doubt they are pinch flats, unless you're really ramming into curbs or something. Are you feeling the rim itself hit? If you are, you need to run a higher pressure.
Yeah sometimes, usually when I get hit on traffic I find a detour, roads here are always bumpy. So it's always a hard time especially for road bike users. Maybe my rims are I guess a little too narrow? I'll try using that talcum powder method for now on.
 

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At almost $100 it's cheaper for him to go tubeless. BTW, sometimes you can go tubeless with just a good tape job and sealant.
But the cheapest at the moment is more air pressure. 30 psi on the road is not very high, and depends on your weight. I'm a lightweight and in my tube days I used to run around 32 on trail, although with skinnier than 2.2 tires. With a 2.35 i could usually get away with 28.
Talc wont hurt, but it only helps marginally. It does help on installtion, helps it to slide and not get caught under the bead.
COnfirm that its pinch flats, they are called snake bites because typically you'll find two punctures right next to each other.
 

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Try a different tire. I run WTB Trail Boss and Vigilante tires with tubes at 22-24 LBS and never experience pinch flats on the rowdiest rockiest trails, including jumps.
 
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