Air pressure and puncture

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wheelsONfire
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by wheelsONfire

Hi guys, i understand most of you run pretty low pressures on your tubeless seat ups!?
But how does that work talking punctures?

I just talked to Clement and a guy working with tires for 50 years.
He recommended my to inflate tires so that they are optimal for tarmac.
I ride about 50-60% tarmac and 40-50% gravel/ trail.

Personally i have found some pressures too low as tires can bottom out.
Ofcourse, a higher pressure works great at tarmac, but it kind of is less ideal on gravel.

However, since i had a puncture at the most lousy place yesterday, i think i need to re-think this.
Perhaps with higher pressure, this had not happened.

Do you guys think some tires actually work better for low pressures than others?
The recommended values is one thing, but part from that it seems some tires actually handle low pressure better.
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bikerector
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by bikerector

I don't think a lot of people are using really low pressures on tubeless setups vs tubed setups for gravel or road. I would definitely not use road pressures for gravel unless it's hardpack or it's only shorts spurts of gravel.

Wider is generally better for gravel, if you have the option. If you can get width in the tires then you need to start figuring out how low you can go without worrying about pinch flatting or damaging rims in potholes or chatter bumps (the worst part of gravel riding IMO). Generally speaking, if I'm running my regular road tires and I know i'm going to hit some gravel sections during my next ride I drop about 10 psi at least out of the tires and I make sure I'm not hitting big potholes. I also grab an extra tube.

What tire size are you running BTW?

rcb78
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by rcb78

I do about 50/50 dirt/road with on WTB Nano's setup tubeless and run about 40 psi up front and 45 psi in the rear. On pure dirt, I will run as low as the high 20's depending on conditions. Have yet to flat on them.

mattr
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by mattr

TBH. On road i run the same pressure tubed or tubeless. Around 3.5 bar.
Probably drop to 3 bar or less for gravel and <2 bar for off road/racing.

Marin
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by Marin

What was the reason for the puncture? With tubeless you shouldn't have any unless you burp or tear the tire.

Generally, lower pressure will help avoid punctures, except for snakebites when running tubes.

mattr
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by mattr

Oh. Forgot to mention. Haven't had a puncture on a cross bike (either of us) in ~10 years.

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wheelsONfire
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by wheelsONfire

Hi guys,....

well, i ofcourse took my Schwalbe G-One off (rear tire).
So i cleaned it well and looked carefully at the inside.
The only thing i could detect was a lateral crack in the casing.

It is like cross-spun casing, and it's along this a crack has been developing.
So close to center of the tire, the compound has given up and here the air leaked out.
I am not sure if the tire was penetrated or not.

However, i tried to patch it but it did not work.
So i decided to just glue it and use a tube.

But then again, i did not dare to ride gravel with a tire like this.
So i collected my new Clement X'plor MSO today.

These proved to be as wide as my Hutchinson (stretched tire and measure side to side and you get 88mm)
I also checked weight and it was 480 grams. Hutchinson is 370 grams and Schwalbe, which is by far the fattest, is 430 grams.

I just mounted them, so i will test ride them tomorrow.

I had hoped the Clement tires would have been a bit fatter (wider) on the rims.

A pity they didn't go for a 38mm version instead of 36.
By spec, Clement should be the widest at 36mm. Schwalbe spec is 35mm and Hutchinson is 34mm.
But in real, Hutchinson and Clement has same width if you unfold the tires.
Perhaps they relate to the pattern of the tire when they specify width?

I don't really know. Anyway, Clement is the most heavy.

If you still wonder how Schwalbe G-One punctured, i am afraid i can't say.
I inflated front to 46 psi and rear to 53 psi.
This has proved best mix for speed and traction at my weight.
Tires had No tubes sealant.

There was no glass or spikes here where i was riding.
So i am still a bit puzzled of how this happened.
I think the tire is far too new to actually crack in the casing and again i point out, this was from the inside!!
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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wheelsONfire
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by wheelsONfire

I have talked alot to Clement about tires and especially X'plor MSO tubeless (36mm/ 480 grams weighthed).
I am amazed that Mike is really firm in his recommendations.
He says i should test 60psi front and 70psi rear.
This is based on my weight, pending 74-78Kg's and the terrain, 50-60% tarmac 50-40% gravel some degree of trail.

That is plenty more than i use and most of you guys seem to use even lower pressure!?

What do you say?
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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addict
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by addict

I've 4000 km on my G-One's tubeless 8) Without punctures or else. Mostely backcountry asphalt roads.
Detect 50% wear at central part of rear tire. Front 10% if any.. My weight 74kg 3,2bar front/2,8 rear.

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wheelsONfire
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by wheelsONfire

Do you run the 35 or 40mm version?

Do you only ride gravel?
It sounds as if that will ride plush, but hell of mushy at tarmac!?

I tried a bit higher pressure at the Clement yesterday (as suggested).
But it feels like a rattle and shake over gravel roads.

Ofcourse higher psi works fine for tarmac,... but the sweet spot where it works really nice, for both gravel and tarmac is a bit difficult.

For now, Hutchinson Black Mamba CX is unbeaten. Wish they made a 38-40mm version of this tire.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

mattr
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by mattr

wheelsONfire wrote:He says i should test 60psi front and 70psi rear.
What do you say?
Far far too high. That's in line with the sort of pressures you'd run on a complete slick road tyre of similar size when run exclusively on tarmac. It's probably why you keep falling off.
Massively overinflated tyres. I'd be starting at about 2/3rds of that.

You've got to remember that for mixed use, every pressure is a compromise, too high you lose traction and comfort and increase rolling resistance, too low and you risk pinch punctures, rolling the tyre and/or burping, and mushy handling, you just need to decide where to go.
Personally, off road i find traction and handling to be king, so low enough to get loads of grip and high enough not to be mushy.

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wheelsONfire
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by wheelsONfire

mattr wrote:
wheelsONfire wrote:He says i should test 60psi front and 70psi rear.
What do you say?
Far far too high. That's in line with the sort of pressures you'd run on a complete slick road tyre of similar size when run exclusively on tarmac. It's probably why you keep falling off.
Massively overinflated tyres. I'd be starting at about 2/3rds of that.

You've got to remember that for mixed use, every pressure is a compromise, too high you lose traction and comfort and increase rolling resistance, too low and you risk pinch punctures, rolling the tyre and/or burping, and mushy handling, you just need to decide where to go.
Personally, off road i find traction and handling to be king, so low enough to get loads of grip and high enough not to be mushy.


Hehe.... i did not say i use that high pressure.
I am with you. I try to get it as high as possible to work for gravel.
As you say, when the pressure is to high it's problem on the gravel.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
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wheelsONfire
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by wheelsONfire

Just mounted the replacement tire G-One.
I got one new tire from Schwalbe since my old was changed (warranty).
Anyone of you guys who actually have been on the 40mm version?

Or even better, been trying both 35 and 40mm version?
I am a bit disappointed in Clement X'plor MSO tubeless.
Personally i think G-One is better.

I think Challenge Gravel Grinder 38mm had been really awesome in a tubeless version.
But it seems it will just not happen.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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