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Once you determined the cold pressure needed for the speed and load on tyres, with maximum reserve at wich comfort and gripp is still acceptable, you can let the cold pressure flow with ambiënt temperature. At least that is the conclusion of this pigheaded Dutch selfdeclared tyrepressure...

When filled 42 psi at 82 degr F, it drops to 37 psi at 38 degr F. If filled with normal air with maximum humidity. If you fill at 68 degr F. the needed pressure you can let it flow with temperature change, is my conclusion in time, and will be proven right in about 20 years Main goal of pressure...

2 systems for tmps sensors. 1. Waking up by a signal sent from receving unit, then even when not driving, mayby after a minute or so, the pressures of that morning. 2. Waking up by movement of the sensor, then you can try to tap the valves to suggests movement to the sensors. So you have to...

Made a tyrepressure/temperature calculator for dry gascompound in tyre (fi Nitrogen filling) and Wet (normal air), in that last I am first, I think. In this RV map So play with it, also part 5, and see that the influence of water in tire is often exagerated by the Nitrogen-lobby. So if you go...

This shows that tirepressure has minimal effect on energy use. At lower speed lesser windforce, so energyloss by tires is relatively more then at higher speed. At 75mph the tire produces a little less heat ( so energyloss) per rotation. per 100miles/kilometers then a little lower energyloss...

You could try out first, to lower the pressure with use of my list. Mayby that is already enaugh for better comfort. And mind that wider tyre needs wider rimm. I made rimmwidth calculator, after contact with Vredestein, and uses ratio's from desighners guide of ETRTO. Also aspect ratio is...

Some feedback after a while would be nice. About energy-use, comfort and tyre-wear. I suspect for people with a heavy foot, to give lesser tyrewear, because better gripp, so lesser slipping. And if you have other size, first look in the other topic if already given, and if not, give loadindex...

First googled the size, and only found XL in 102 loadindex. So your tires are LI 102 / maxload 850kg/ 1874 lbs AT 42 psi ( 2.9 Bar) upto 99mph/160kmph. Official system is Y upto 220kmph/??mph but this " pigheaded Dutch selfdeclared tyrepressure specialist" dont believe that, so keep using...

That list in former post is calculated with a safe formula, but no reserve build in, and is for max 160kmph/99mph. In the lists I make and given in the topic I linked to in my first post here, I use an even safer formula that leads to lower loadcapacity for the pressure, and give 90% of that...

I dont believe Tesla spent a lot of effort in tire pressure recommendation, yust high for high actiradius, and that comfort and gripp sucs then, they dont care about. Did you have mayby indirect low pressure message in your former cars? They can be reset even if you give all tires much to low...

Look at this topic, in wich I give lists and explanation. Change of tyre pressure if using 255/50/19 107Y due to higher load rating But tmps alarm is a secundary problem. Porche uses lower alarmsettings if comfort setting used. Mayby Tesla too. Once the signal of sensor is receved in the...

XL LI 104 / maxload 900kg/1984lbs AT 42 psi upto 160kmph/99mph Kg axleload/cold psi/ Lbs axleload 835 kg/ 20 psi / 1842 lbs 872 kg/ 21 psi / 1922 lbs 908 kg/ 22 psi / 2002 lbs 944 kg/ 23 psi / 2082 lbs 980 kg/ 24...

Now for 101 loadindex /maxload 825kg/1819 lbs. AT 42psi so XL KG axleload/cold psi/LBS axleload 766 kg/ 20 psi / 1689 lbs 799 kg/ 21 psi / 1762 lbs 832 kg/ 22 psi / 1835 lbs 865 kg/ 23 psi / 1908 lbs 898 kg/ 24 psi...

Joined in an other topic on this forum, and pointed to this topic. Was in the UK and Ireland part, so will give the lists for KG and LBS. 1 or 2 years ago Continental introduced the HL for High Load especially for the heavyer electric cars. Is a tire with about 3 loadindex steps higher then...

Dontblowervthevpressure in the blind, you risk using to low pressure for the axleloads and speed used. Then the most important is that you determine the axleloads in your use acurately, the most tricky part in it all, and your responcibility. Most accurate is by weighing per axle in the...

The 21 inch front 98 ( loadindex) assuming they are all XL, already given in second list. Can make for 2 in one list, if you give if in KG or LBS. Or do you want both. About reserve for unequall weight. I once determined by reactions about bumping, that if less then 85% of weight calculated...

If that is the 107 loadindex AT 42 psi, from the first list I gave, 37 psi is even above as needed for GAWR rear, so wil give still verry acceptable actiradius of one battery filling, but better comfort. Front then can even be lower. Asuming you have the same GAWR's and weights as topicstarter (...

That is because I build in a reserve, is 90% of 1500kg. So if your axleload is 1350kg,you will search back and find 42 psi, and so use 90% of the loadcapacity calculated for 42 psi. This gives maximum reserve but still no bad comfort. You need that reserve for things like. 1. Pressure loss in...

Here the list for 98 loadindex, 750kg/ 1653lbs AT 42 psi up to 99mph. Kg axle/ cold psi/ LBS axle 696 kg/ 20 psi / 1534 lbs 726 kg/ 21 psi / 1601 lbs 756 kg/ 22 psi / 1668 lbs 787 kg/ 23 psi / 1734 lbs 817 kg/ 24...

Here the promessed list. For every tire with loadindex 107 XL so at 42 psi. If you want it for higher speed, give that speed, you wont go over for even a minute, and I make a list for that. Given in KG and LBS for the psi, Given 90% of axleloadcapacity calculated for the psi, for max speed...

All the tires mentioned are XL, and those are allowed maxload at 160kmph/99mph AT 42 psi. The 50 psi is the maximum allowed cold pressure, and difference is used to highen up the maxloadpressure of 42 psi, for higher speed, with a system depending on speedcode of tire, in the official used...

We could conversate in Dutch, when you mail me at my hotmail.com addres with username jadatis ( like this to prevent spamm, combine yourselves. But then the others wont learn from it. About the weight division: The 2 persons in front are sitting with their gravitypoint ( at belly button) a...

Achter is dan misschien zwaarder , maar daar zitten ook banden met meer draagvermogen. Voor 96Y = max load 730kg per band, dus je MTA ( GAWR) is maximaal 1460kg, en tot 160kmpu heb je voor die 730kg 2,9 bar nodig( Y snelheidscode gaat officiël van 220kmpu uit, maar houdt het maar op 160kmpu)...

That orange tire was probably 0.3 psi lower then the rest, so set the alarm. Some tmps sensors send pressure to unit in 0,5 psi steps, but unit only gives it to you in 1psi steps. But the 42 psi is extreme high for energysaving so actiradius of battery. Dont you have a comfort setting for the...

You must never lower the cold measured pressure on a hot day to given advice. In the list I gave, you need the 45 psi when outside 93 degrF to give lesser deflection so heatproduction, then the 42 psi. Cooling down is also worse then , because temperature-differences between critical temp of...

Advice pressure is cold measured, and that is simply when air in tire has same temperature as outside the tire. Advice is given for 65 degrF. So when measured on a hot day 90 degr F , you have to calculate back the pressure to 65 degr F. It then is still called cold pressure. Will give a...

In my post #43 , I already wrote that normal air is even better then pure Nitrogen filling, but here some more facts. First, they dont purge the tire vacuüm before filling with 100% Nitrogen. It would not be good for the tire. So the only way to come close to 100% N2 is to fill with 100% N2...

This is a document I made years ago, and turned it around, that filling with normal air with all the water in it, is even better then with pure Nitrogen. Try to demith this. Filling car tires with normal air is better then with Nitrogen. A. Oxygen, which makes 21% of normal outside air...

In my post #22 i roughly calculated for 75mph , rolling resistence makes 14.5% of total energy use So in your case 14.4% of 235wh/m( used wronly Kw/m) is 34wh/m, leaves 201wh/m for the rest . Now going from 48 to 42 gives 48/42= 1.142 times as much surface on the ground, so 1.142^2 is 1.306...

I claim to be able to roughly calculate the fuelsaving. For that I concluded next . Rollong-resistence makes about 25% of the fuelconsumption when driving 80km/50mph, with the calculated needed pressure for the load on tire and max speed of 160kmph/99mph. 2 times the speed gives 2 times...

On normal car tires, only max allowed cold pressure is given on sidewall, between 44 and 51psi, and XL/ reinforced/ extraload, sometimes even 60 psi( Toyo) . The cold pressure for wich maxload is calculated is called reference- pressure in official system, and for standard load is 36 psi , and...

I once got hold of the official European used formula for calculating tyrepressure for a load on tyre and system for speed used, and went running with it. Now I use my own determined formula, and system for speed, to idea of an article of an american IR J.C.Daws. I concuded in time that...

With the info on plates, I calculated pressures for GAWR's +10%, so enaugh reserve for fully loaded and 99mph. And no bumping. Gave F 32 psi and R 38 psi. The 42 and 45 is yust for actiradius of battery, and normal use axleweights is probably so 32 psi all around is needed. Especially front...

Then you forget that the pressure in tire is 14,7 psi higher then the outside air, so first add that before you calculate lineair from absolute zero temp ( - 459.67) , the n afterward substact the 14.7 psi again. Doing that , might give that 1psi/10degrF. Rule of tumb. Better would be a...

I expect it to be a software thing. Some TMPS compensate for temperature. Then the little tmps- computer in car calculates the pressure back to 65 or 68 degr F. Mayby with the update, that has chanched. Did you read the 45 psi ( much to high to my opinion) on your screen or on the pressure...

To my conclusions the 42 psi is only done for the actiradius of the battery, and 35 psi is more then enaugh for the larger weight on the tires with more maxload then average, so completely save up to high speed, and even wear of treath. But have to calculate it , for that I need those weights...

But dont say its a subject of research for Tesla, in the end it might prove to be also go for machine driven vehicles. maiby not in the same amount , but still a tihing to do research about. After a few year mayby TomB985 notices not that much energy loss as would be expected. I mean to be...

A totally other vehicle , a bicycle, they discovered that at a sertain point , higher pressure did not give lesser energy to use per mile. Known in this field is Jan Heine, who did much reasearch on pressure for bicycles. There it has to do with the human body wich gives vibrations and so the...

No I state that the rolling resistence chanches with pressure. But you realised that a day later, but then could not edit your post anymore. Rolling circumference also changes with pressure, also for a radial tire. The distance the tire makes a cicle is not 3.1415 times unloaded diameter...

Made new calc, old was wrong, and it shows less loss at lower pressure. Filled in reference 50mph , 25% of total energy used by rolling resistece, 32 psi, and made actiradius so that it became 250miles at 42 psi and 65mph. In first version I did speed / speed squaire,and that is right for...

Been playing with excell for the actiradius of battery for speed and pressure Filled in as reference that at 65mph constant speed and 42 psi pressure and 250miles actiradius, and spreadsheet gives list for other speeds and pressures. Try to copy it , but can be messy. pressure》...

In other topic on this forum, I read about centerwear with 42 psi, so ,though you can go pretty high in pressure before that happens, this border is reached. And if on other cars with same weights, 32 psi gives a good ride, why would it not be for Tesla.

Here a temp/ pressure tabel. Tmps sensors in the tire measure the absolute pressure , and software of unit in the car substracts a fixed outside pressure of most likely 1013 mbar.

Even the 42 psi can be bumpy, and even centrewear, because advice is given for actiradius of battery. I have to calculate it , but probably even 30 psi is enaugh for savety of tires, up to top speed and fully loaded.

If the 45 psi was the lowest safe pressure calculated for speed and load on tires, you could not lower it for safety reasons. But on electric cars, the pressure advice is kept verry high for actiradius of battery. That high even, so often centrewear of tires so lower milage of tires. That lowest...

Pressure advice for electric cars are given extreme high for reasons of high actiradius of battery. Because of the tires being still oversised for the higher weight, safe lowest pressure is probably about 30 psi. Now you can sooner go higher without centrewear then lower without sideswear, but...

If you see the pressure go up when tires warm up by driving, then it is not a compensating TMPS. But the high pressures for electric cars ( and bycicles) is done for more actiradius. For savety, so your tires wont overheat,when driving the speed the pressure is calculated for, you probably...

Some TMPS-systems compensate for temperature. So they then give pressure as it would be for 18 or 20degr C ( 65 or 68 degr F) . I dont knoq if Tesla also uses them If you then fill to 47 psi when hot outside , the device you use gives 47 ( or % inacurate) , but TMPS in car gives lower. When...

For savety of tires it is not needed to highwn up the pressure, if calculated back to 18degrC / 65degrF you have the 42 psi, you are safe. For axiradius you can fill it to 42 at for instance freesing point ambiënt tmp. But electric cars and bicicles have high advice pressure for axitradius...

For savety of tires you dont have to worry. So no overheating expected because of the more deflection the lower pressure gives. The relatively high pressure of every vehicle with battery, is done for lesser rolingresistance. You could ask to lower the alarmsetting, and accept a lower actiradius...