Max Tire Pressure Label (700 x 32)
#76
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"Informed opinion? Thats rich! :-)
You and NS are the ones making unusual claims, regurgitating the HED blurb and then ask others to do the homework to back it up."
And yes you did do that, in #67 , but now YOU are shifting the goal posts. That wont win you any medals. Its too obvious.
#77
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The claims are unusual to you because you don’t know much about this topic.
There’s no homework needed here. All the understanding that is needed is to know that larger volume requires less pressure to maintain the same “hardness”. You should be able to see that by pumping your 23’s up to 120 psi and comparing them to a MTB tire pumped up to 45 psi. Feels about the same. A wider rim creates more volume, hence, less pressure.
There’s no homework needed here. All the understanding that is needed is to know that larger volume requires less pressure to maintain the same “hardness”. You should be able to see that by pumping your 23’s up to 120 psi and comparing them to a MTB tire pumped up to 45 psi. Feels about the same. A wider rim creates more volume, hence, less pressure.
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You're arguing against people who know what they're talking about. This isn't going to end well...
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#79
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Btw, Im all ears.
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Run your tires however you like. Feel free to ignore the manufacturers recommended pressures. These are not MY claims. That chart is from HED Wheels. I’ll go out on a limb and say that they know significantly more about what works on THEIR products than you do...especially since you seem to have literally no experience whatsoever with what we are talking about.
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As I’ve said before (numerous times now), a wider rim creates more volume. More volume requires less pressure. Boyle’s law.
A 23c road tire on a wide rim will have 33% more volume than on a narrow rim (if not more). I’ve done this in a calculator to remove all doubt. If this doesn’t help, I’m not sure it’s worth discussing further.
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#82
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Run your tires however you like. Feel free to ignore the manufacturers recommended pressures. These are not MY claims. That chart is from HED Wheels. I’ll go out on a limb and say that they know significantly more about what works on THEIR products than you do...especially since you seem to have literally no experience whatsoever with what we are talking about.
You were the one posting the chart as gospel in relation to a not HED rim with a not HED tyre. Therefore you are the one making the clam. There is an inherent claim in your posts, that doing so is fundamentally different because you run a rim that is a few mm wider and that doing so is "better". Better how?
You cant keep answering these questions with claims that it is all self evident and "you have no experience". Thats not answer. Its just a cop out and a distraction.
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There is nothing magic about running lower than normal pressure. I, and everyone else, can do that as well on a 17c rim and get away with it on every road around where i live.That doesnt prove anything other than its possible.
You were the one posting the chart as gospel in relation to a not HED rim with a not HED tyre. Therefore you are the one making the clam. There is an inherent claim in your posts, that doing so is fundamentally different because you run a rim that is a few mm wider and that doing so is "better". Better how?
You cant keep answering these questions with claims that it is all self evident and "you have no experience". Thats not answer. Its just a cop out and a distraction.
You were the one posting the chart as gospel in relation to a not HED rim with a not HED tyre. Therefore you are the one making the clam. There is an inherent claim in your posts, that doing so is fundamentally different because you run a rim that is a few mm wider and that doing so is "better". Better how?
You cant keep answering these questions with claims that it is all self evident and "you have no experience". Thats not answer. Its just a cop out and a distraction.
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#84
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There is nothing magic about running lower than normal pressure. I, and everyone else, can do that as well on a 17c rim and get away with it on every road around where i live.That doesnt prove anything other than its possible.
You were the one posting the chart as gospel in relation to a not HED rim with a not HED tyre. Therefore you are the one making the clam. There is an inherent claim in your posts, that doing so is fundamentally different because you run a rim that is a few mm wider and that doing so is "better". Better how?
You cant keep answering these questions with claims that it is all self evident and "you have no experience". Thats not answer. Its just a cop out and a distraction.
You were the one posting the chart as gospel in relation to a not HED rim with a not HED tyre. Therefore you are the one making the clam. There is an inherent claim in your posts, that doing so is fundamentally different because you run a rim that is a few mm wider and that doing so is "better". Better how?
You cant keep answering these questions with claims that it is all self evident and "you have no experience". Thats not answer. Its just a cop out and a distraction.
You can quote everything written about it, but without any personal experience, you have nothing to add here..
Last edited by noodle soup; 12-31-19 at 12:30 AM.
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I summarized.. they actually break the 80-95 down (eg. 3-6 psi increments) more than HED based on weight.. eg. 140-150lbs, 150-160, etc.. HED only has 140-180 as a single category.
Enve states these as starting pressures based on Tubeless. Even so, though we know that eg. 70psi TL will be better than 70psi tubed, but do we know that recommended 72psi TL is better than 80 or 85psi TL? If so, in what way is it better (comfort only, speed only, comfort and speed)?
Enve states these as starting pressures based on Tubeless. Even so, though we know that eg. 70psi TL will be better than 70psi tubed, but do we know that recommended 72psi TL is better than 80 or 85psi TL? If so, in what way is it better (comfort only, speed only, comfort and speed)?
#86
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I did. I have a hard time believing in your 33% claim. Where did that come from?
"So, how to increase the air volume? Here are few measurements:
Width Width change Air volume difference (mL) Difference 17mm rim Tyre 23–>25 144,25 15,0% 25mm tyre Rim 17 –> 19 24,04 2,2% A 2mm increase of the tyre width alone has a much higher impact (+15%) than a 2mm increase of the rim width alone (+2.2%).
And of course, the combination leads to both air volume increases, which is even better."
THE RIGHT TYRE WIDTH ON THE RIGHT RIM WIDTH - Engineerstalk : Engineerstalk
I cant see what Boyles law is supposed to prove. It only says if you inflate the bigger tyre/rim combination, with the same amount of gas, the pressure will be lower, if temperature is kept the same. Doh!
However that is not proof 72psi is adequate for a 23mm tyre. At best its an indication that IF 72psi is right for a 23mm then 62psi is also right for a 28mm.
Btw, no one disputed a bigger volume tyre "requires" less pressure, only the numbers in the chart are unusually low. Stop acting like we are all imbeciles.
"So, how to increase the air volume? Here are few measurements:
Width Width change Air volume difference (mL) Difference 17mm rim Tyre 23–>25 144,25 15,0% 25mm tyre Rim 17 –> 19 24,04 2,2% A 2mm increase of the tyre width alone has a much higher impact (+15%) than a 2mm increase of the rim width alone (+2.2%).
And of course, the combination leads to both air volume increases, which is even better."
THE RIGHT TYRE WIDTH ON THE RIGHT RIM WIDTH - Engineerstalk : Engineerstalk
I cant see what Boyles law is supposed to prove. It only says if you inflate the bigger tyre/rim combination, with the same amount of gas, the pressure will be lower, if temperature is kept the same. Doh!
However that is not proof 72psi is adequate for a 23mm tyre. At best its an indication that IF 72psi is right for a 23mm then 62psi is also right for a 28mm.
Btw, no one disputed a bigger volume tyre "requires" less pressure, only the numbers in the chart are unusually low. Stop acting like we are all imbeciles.
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Run your tires however you like. Feel free to ignore the manufacturers recommended pressures. These are not MY claims. That chart is from HED Wheels. I’ll go out on a limb and say that they know significantly more about what works on THEIR products than you do...especially since you seem to have literally no experience whatsoever with what we are talking about.
- Maximum tire pressure for this rim is 120psi when used with an inner tube and 100psi when running the wheel set-up tubeless. Please do not exceed the maximum pressure stated on your tire.
- Maximum tire pressures for other tire sizes 30mm do not exceed 70psi, 33mm do not exceed 50psi, 35-45mm do not exceed 40psi, 46mm+ do not exceed 35psi.
- Please do not exceed the maximum pressure stated on your tire.
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23mm tire in a perfect cylinder: (2097mm ((pi)((11.5)^2))) 871,252 ml
26mm now because of the wide rim: (2110mm ((pi)((13)^2))) = 1,120,261 ml
Oh, so now you agree that a tire with a bigger volume due to having a wider rim needs less pressure. Great. Moving on.
You remind me of my ex. She would always put words and feelings in my mouth as well. Are you my ex?
...or are you just an elaborate troll, and I keep taking the bait?
Methinks your name is a misnomer.
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#91
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Math. A 23mm tire will "open up" to 26mm on a wide rim. Larger diameter tire plus larger rim chamber = significantly more volume than you would think. If we treat the tire like a perfect cylinder and forget the added volume of the rim chamber (which adds to the percentage), the tire alone sees a 28% increase in volume.
23mm tire in a perfect cylinder: (2097mm ((pi)((11.5)^2))) 871,252 ml
26mm now because of the wide rim: (2110mm ((pi)((13)^2))) = 1,120,261 ml
And on a wide rim with more V O L U M E that a narrow rim, it is unequivocal, indisputable, and absolute proof. But again, you seem to be missing that point completely....still.
.
23mm tire in a perfect cylinder: (2097mm ((pi)((11.5)^2))) 871,252 ml
26mm now because of the wide rim: (2110mm ((pi)((13)^2))) = 1,120,261 ml
And on a wide rim with more V O L U M E that a narrow rim, it is unequivocal, indisputable, and absolute proof. But again, you seem to be missing that point completely....still.
.
Here's Schwalbe's recommended inflation chart. Who's right and who's wrong and what supports this?
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The disconnect in this conversation is that while everyone agrees that wider tires need less PSI, some wheel makers seem to go way too far in their reduction. IOW, 72psi wouldn't be correct for a 26mm tire either.
Here's Schwalbe's recommended inflation chart. Who's right and who's wrong and what supports this?
Here's Schwalbe's recommended inflation chart. Who's right and who's wrong and what supports this?
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The disconnect in this conversation is that while everyone agrees that wider tires need less PSI, some wheel makers seem to go way too far in their reduction. IOW, 72psi wouldn't be correct for a 26mm tire either.
Here's Schwalbe's recommended inflation chart. Who's right and who's wrong and what supports this?
Here's Schwalbe's recommended inflation chart. Who's right and who's wrong and what supports this?
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Given Schwalbe's recommendation od 100 psi for a 25mm tire provided by Sy Reene , the following can be mathematically provided for a wider rim.
My 25mm GP5k's measure out to nearly 30mm on my HED Plus rims, so I used 30mm as the final diameter for simplicity.
25mm cylinder volume: 1033289 ml
30mm cylinder volume: 1516918 ml
Applying Boyle's Law, the final pressure can be given by P1V1 = P2V2, or this fun screenshot I took for conveniences sake:
If your 25mm Schwalbe opened up to 30mm on a wide rim, your final pressure would be 68.12 psi for a comparable ride quality.
My 25mm GP5k's measure out to nearly 30mm on my HED Plus rims, so I used 30mm as the final diameter for simplicity.
25mm cylinder volume: 1033289 ml
30mm cylinder volume: 1516918 ml
Applying Boyle's Law, the final pressure can be given by P1V1 = P2V2, or this fun screenshot I took for conveniences sake:
If your 25mm Schwalbe opened up to 30mm on a wide rim, your final pressure would be 68.12 psi for a comparable ride quality.
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If the tire is measured to be 25mm on a wider rim, I would personally use the values for a 25mm tire and see how it rode. Wider rims tend to change the overall shape of the tire and how they "act" (for the better, in my opinion), so it's up to the user at that point. I found a slightly higher pressure to corner better at speed, so I'm 1-3 psi higher than recommended.
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#100
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Given Schwalbe's recommendation od 100 psi for a 25mm tire provided by Sy Reene , the following can be mathematically provided for a wider rim.
My 25mm GP5k's measure out to nearly 30mm on my HED Plus rims, so I used 30mm as the final diameter for simplicity.
25mm cylinder volume: 1033289 ml
30mm cylinder volume: 1516918 ml
Applying Boyle's Law, the final pressure can be given by P1V1 = P2V2, or this fun screenshot I took for conveniences sake:
If your 25mm Schwalbe opened up to 30mm on a wide rim, your final pressure would be 68.12 psi for a comparable ride quality.
My 25mm GP5k's measure out to nearly 30mm on my HED Plus rims, so I used 30mm as the final diameter for simplicity.
25mm cylinder volume: 1033289 ml
30mm cylinder volume: 1516918 ml
Applying Boyle's Law, the final pressure can be given by P1V1 = P2V2, or this fun screenshot I took for conveniences sake:
If your 25mm Schwalbe opened up to 30mm on a wide rim, your final pressure would be 68.12 psi for a comparable ride quality.