Tire Pressure
#52
Senior Member
Join Date: Oct 2013
Location: Mich
Posts: 7,524
Bikes: RSO E-tire dropper fixie brifter
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Liked 3,089 Times
in
1,972 Posts
I'd prefer to ride at the lower recommended PSI for TL, but with how bad the surface conditions are where I ride, it'd heavily increase the probability of needing wheel servicing.
__________________
-Oh Hey!
-Oh Hey!
#53
Senior Member
Join Date: May 2018
Location: Fargo ND
Posts: 918
Bikes: Time Scylon, Lynskey R350, Ritchey Breakaway, Ritchey Double Switchback, Lynskey Ridgeline, ICAN Fatbike
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 474 Post(s)
Liked 557 Times
in
314 Posts
Likes For DangerousDanR:
#54
Senior Member
Join Date: Aug 2019
Location: Québec, Canada
Posts: 2,154
Bikes: SL8 Pro, TCR beater
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 1019 Post(s)
Liked 593 Times
in
446 Posts
And I never liked German cars neither. I always owned Japanese cars up until my current one (Tesla). Most of my friends back when I started driving owned VW and Audis and were often stuck at the garage with hefty repairs bills. Bosch parts here, Bosch parts there, special order here, special order there... But hey, they wanted to be original
#55
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
#56
Senior Member
Join Date: May 2018
Location: Fargo ND
Posts: 918
Bikes: Time Scylon, Lynskey R350, Ritchey Breakaway, Ritchey Double Switchback, Lynskey Ridgeline, ICAN Fatbike
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 474 Post(s)
Liked 557 Times
in
314 Posts
I'm currently using an electronic pressure sensor in a couple of products. The one we use is cheap and it reports temperature and pressure. We do the correction in software.
It is a MEMS sensor and temperature dependence (beyond normal gas physics) is a function of how they work.
The car reads low, but not very much low. Not enough discrepancy to cause trouble either way. Jaguar calls for 47 PSI in the rear, so running 45 on the TPMS set at near freezing will be okay all winter.
I don't see any caveats about temperature in the JACO data. If I wanted, I could check the JACO against a calibrated sensor at work.
It is a MEMS sensor and temperature dependence (beyond normal gas physics) is a function of how they work.
The car reads low, but not very much low. Not enough discrepancy to cause trouble either way. Jaguar calls for 47 PSI in the rear, so running 45 on the TPMS set at near freezing will be okay all winter.
I don't see any caveats about temperature in the JACO data. If I wanted, I could check the JACO against a calibrated sensor at work.
Last edited by DangerousDanR; 12-01-23 at 07:32 AM.
#57
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
I'm currently using an electronic pressure sensor in a couple of products. The one we use is cheap and it reports temperature and pressure. We do the correction in software.
It is a MEMS sensor and temperature dependence (beyond normal gas physics) is a function of how they work.
The car reads low, but not very much low. Not enough discrepancy to cause trouble either way. Jaguar calls for 47 PSI in the rear, so running 45 on the TPMS set at near freezing will be okay all winter.
I don't see any caveats about temperature in the JACO data. If I wanted, I could check the JACO against a calibrated sensor at work.
It is a MEMS sensor and temperature dependence (beyond normal gas physics) is a function of how they work.
The car reads low, but not very much low. Not enough discrepancy to cause trouble either way. Jaguar calls for 47 PSI in the rear, so running 45 on the TPMS set at near freezing will be okay all winter.
I don't see any caveats about temperature in the JACO data. If I wanted, I could check the JACO against a calibrated sensor at work.
The analogue gauges on my 2 track pumps also seem consistent. I often hear about how inaccurate they can be, but mine seem pretty good.
#58
Senior Member
Join Date: Oct 2008
Location: Portland, OR
Posts: 3,881
Bikes: Trek Domane SL6 Gen 3, Soma Fog Cutter, Focus Mares AL, Detroit Bikes Sparrow FG, Volae Team, Nimbus MUni
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 913 Post(s)
Liked 2,097 Times
in
1,101 Posts
I think it's beyond the capability of virtually anyone on here to determine ideal tire pressure for speed, any more accurately than +/- 5 psi. Heck, probably 10psi. Too many variables, too many unknowns, too much subjective assessment, not enough good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
#59
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
I think it's beyond the capability of virtually anyone on here to determine ideal tire pressure for speed, any more accurately than +/- 5 psi. Heck, probably 10psi. Too many variables, too many unknowns, too much subjective assessment, not enough good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
#60
Senior Member
Join Date: Aug 2019
Location: Québec, Canada
Posts: 2,154
Bikes: SL8 Pro, TCR beater
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 1019 Post(s)
Liked 593 Times
in
446 Posts
I think it's beyond the capability of virtually anyone on here to determine ideal tire pressure for speed, any more accurately than +/- 5 psi. Heck, probably 10psi. Too many variables, too many unknowns, too much subjective assessment, not enough good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
Not a big deal anyways. Most cyclists only want to feel good on their bikes and they find a certain pressure that suits their needs.
#61
Senior Member
If your tubeless wheels are hookless, you do indeed have to reduce your pressure by a lot to be safe per ETRTO. Make sure you also abide by the tire and rim manufacturers specifications -- ie. go with the lowest of the sources. See Silca disclaimer I pasted below
96R/85F -- that seems like a much larger difference than Silca's calculator usually returns between rear and front. Are you running different width tires in Front vs Rear?
96R/85F -- that seems like a much larger difference than Silca's calculator usually returns between rear and front. Are you running different width tires in Front vs Rear?
That must be a new concept.
#62
Senior Member
I think it's beyond the capability of virtually anyone on here to determine ideal tire pressure for speed, any more accurately than +/- 5 psi. Heck, probably 10psi. Too many variables, too many unknowns, too much subjective assessment, not enough good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
I'd go further and speculate that even with all possible simulation capability, computing power, and eliminating rider weight and road smoothness variables, it's still too hard. Not that a number couldn't be calculated, but there are still variables and lack of good data.
#63
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
The Zipp pressure calculator is what I've been using for the last 3 years, since going tubeless on hooked rims for a year, then on to wider hookless rims. It's simple to put in all necessary information, except for tire casing. I have to decide whether thin or standard is most appropriate for the top level hookless compatible tires like the Pirelli P-Zero tires that I use. Thinner casing, requires more pressure. I've been using something in between thin and standard. It's only a suggestion and up to the rider to decide what they prefer.
#64
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,670
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4763 Post(s)
Liked 1,542 Times
in
1,011 Posts
..and road condition and tire's inflated width. And it lets you choose rim type, but not tire type but I guess we'll assume nobody uses tubed tires on a tubeless rim :-)
Likes For Sy Reene:
#65
Senior Member
Join Date: Mar 2022
Location: Missoula MT
Posts: 1,792
Bikes: Handsome xoxo, Serotta atx, Canyon Endurace CF8
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 908 Post(s)
Liked 1,950 Times
in
863 Posts
I like the silca one but how does one know what speed to put in? what is a fast group ride or moderate group ride? ultimately I end up going with the firm setting from the Rene Herse calculator which is quite a bit higher than either of the other two...
#66
Senior Member
It would be strange to buy expensive tubeless tires and use tubes in them. The recommended pressure for tubeless might result in pinch flats with tubes. I carry a spare tube, since it might be needed with a damaged tire, but I wouldn't use tubes in them.
#67
Senior Member
Join Date: Jul 2009
Posts: 6,051
Bikes: Colnago, Van Dessel, Factor, Cervelo, Ritchey
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 4008 Post(s)
Liked 7,504 Times
in
3,023 Posts
#68
I like bike
Join Date: Feb 2021
Location: Merry Land USA
Posts: 662
Bikes: Roubaix Comp 2020
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked 283 Times
in
191 Posts
Like many I have been on this slow increase in tire width and slow decrease in pressure. Currently I am running 30mm (31mm actual) GP5000 S TR tubeless at around 50-55psi for my 170lb me+bike weight. In the summer I will bump that up ~5psi. The Silca calculator says 65psi for me.
When I first got the 30mm tires I was running 70psi which probably gives optimal speed on reasonably smooth pavement, but the handling is so much better at lower pressures, both for smoothness of the ride and for grip when you need it. Especially in winter I really appreciate the lower pressure as the roads are wet much more often and the grip can be minimal at times.
When I first got the 30mm tires I was running 70psi which probably gives optimal speed on reasonably smooth pavement, but the handling is so much better at lower pressures, both for smoothness of the ride and for grip when you need it. Especially in winter I really appreciate the lower pressure as the roads are wet much more often and the grip can be minimal at times.
Likes For scottfsmith:
#69
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
Like many I have been on this slow increase in tire width and slow decrease in pressure. Currently I am running 30mm (31mm actual) GP5000 S TR tubeless at around 50-55psi for my 170lb me+bike weight. In the summer I will bump that up ~5psi. The Silca calculator says 65psi for me.
When I first got the 30mm tires I was running 70psi which probably gives optimal speed on reasonably smooth pavement, but the handling is so much better at lower pressures, both for smoothness of the ride and for grip when you need it. Especially in winter I really appreciate the lower pressure as the roads are wet much more often and the grip can be minimal at times.
When I first got the 30mm tires I was running 70psi which probably gives optimal speed on reasonably smooth pavement, but the handling is so much better at lower pressures, both for smoothness of the ride and for grip when you need it. Especially in winter I really appreciate the lower pressure as the roads are wet much more often and the grip can be minimal at times.
#70
Perceptual Dullard
Join Date: Sep 2009
Posts: 2,475
Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 950 Post(s)
Liked 1,213 Times
in
523 Posts
Hmmm. I think it's within the capability of several, possibly many, riders here -- but doing so is kinda tedious and boring. They *could* do it, but they don't want to, and as long as there are reasonably easily accessible online calculators available, there's not much need.
Likes For RChung:
#71
Senior Member
But don’t worry, I fully understand bastardization of language. 😉
#72
Senior Member
Do I really have to explain? OK. Let me try...
In the Beatles movie "Help" there is a scene where the "baddie" points a pistol at Mr. Starkey. He in turn sticks his finger in the barrel and says, "It's British you know...won't work." Like the old joke about warm beer and Lucas refrigerators.
I have owned three British motor vehicles: a Norton Commando (with a Boyer-Bransden ignition that would stop working when the temperature was above 90F), a Series II land Rover, and my current Jaguar XE. All three of them have been absolute hoots to drive in their preferred environment. Not a one of them was what you might call reliable. I have also tried to buy two Lotus automobiles, but the deals fell through.
In the Beatles movie "Help" there is a scene where the "baddie" points a pistol at Mr. Starkey. He in turn sticks his finger in the barrel and says, "It's British you know...won't work." Like the old joke about warm beer and Lucas refrigerators.
I have owned three British motor vehicles: a Norton Commando (with a Boyer-Bransden ignition that would stop working when the temperature was above 90F), a Series II land Rover, and my current Jaguar XE. All three of them have been absolute hoots to drive in their preferred environment. Not a one of them was what you might call reliable. I have also tried to buy two Lotus automobiles, but the deals fell through.
He should have realized when Ford ownership actually improved the quality of Jaguar. Now it’s ownered by Tata (an Indian company known for its unsafe and unreliable crap vehicles) but the guy keeps going back to it. 🤪
#73
Senior Member
A couple of days ago I topped up tyre pressures on our 2 cars using a cheap portable compressor with a built-in digital gauge. I set all 8 tyres to 40 psi on the gauge and all 8 TPMS sensors reported 40 psi. I was actually quite surprised none of them read slightly different! But now when I think back to other cars I’ve owned, I can’t actually remember a TPMS sensor reading low/high relative to my Topeak digital gauge.
The analogue gauges on my 2 track pumps also seem consistent. I often hear about how inaccurate they can be, but mine seem pretty good.
The analogue gauges on my 2 track pumps also seem consistent. I often hear about how inaccurate they can be, but mine seem pretty good.
I added air to four tires of my car (excluding the spare), each of the four tires were off by 1-3 PSI. An external high quality digital meter was used fill exactly 36PSI. The gauge in the reported inconsistently lower numbers. I’m not sure if individual pressure sensors can be recalibrated,
As for bicycles tire pressure, I have always liked to use a few PSI lower pressure than the maximum. On 25mm I usually use around 70-75 PSI.
#74
Senior Member
Join Date: May 2021
Posts: 8,732
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 4554 Post(s)
Liked 5,074 Times
in
3,129 Posts
40 PSI? A lucky coinkidink!
I added air to four tires of my car (excluding the spare), each of the four tires were off by 1-3 PSI. An external high quality digital meter was used fill exactly 36PSI. The gauge in the reported inconsistently lower numbers. I’m not sure if individual pressure sensors can be recalibrated,
I added air to four tires of my car (excluding the spare), each of the four tires were off by 1-3 PSI. An external high quality digital meter was used fill exactly 36PSI. The gauge in the reported inconsistently lower numbers. I’m not sure if individual pressure sensors can be recalibrated,
It also helps my “luck” in that my compressor actually targets 0.5 psi higher than the nominal setting. So it sets my tyres pressures to an indicated 40.5 psi. Which means that the TPMS sensors are less likely to read 39 or 41 psi because they don’t round their readings up or down. So 40.1 and 40.9 both display as 40.
#75
Newbie
Thread Starter