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Re: Tyre pressure

PostPosted: Mon, 13 Feb 2017 5:25 +0000
by Toeknee2
I have the Michelin latitude (tour hp) @ 30PSI
Built for 90% road 10% off road.
Super quiet, extra grippy and will last close to 100K (apparently)

Re: Tyre pressure

PostPosted: Mon, 13 Feb 2017 5:44 +0000
by NZMarkb
Lower pressures ride nice but you will pay for it at the pump
I know it will only be minimal but it does make a difference

Re: Tyre pressure

PostPosted: Mon, 13 Feb 2017 5:25 +0000
by hylux
Been running 40psi for years, great handling, great tyre wear and great watching the wifes boobs bouncing

Re: Tyre pressure

PostPosted: Mon, 13 Feb 2017 6:43 +0000
by ktm300
hylux wrote:Been running 40psi for years, great handling, great tyre wear and great watching the wifes boobs bouncing


Agree with the boobs comment but that's about it .

Re: Tyre pressure

PostPosted: Tue, 14 Feb 2017 2:03 +0000
by adamkberger
I also used to run 38-40psi in my Landcruiser, but that vehicle had 16" wheels with 32" tyres not 18" wheels with 30.5" tyres. They were a lot more forgiving due to the larger sidewall. The price you pay for modern aesthetics.

Re: Tyre pressure

PostPosted: Tue, 14 Feb 2017 2:37 +0000
by hylux
I think the OP by Tone raises a good point about dealers delivery but also check them after a service. I have had them drop them to 30 psi. Probably by an apprentice told so for cars.
Everyone will run different pressure depending on tyres, suspension, weight, roads you drive on etc. But you need to regularly check and find your sweet spot. In the last 4 utes I've had they were all different

Re: Tyre pressure

PostPosted: Tue, 14 Feb 2017 4:25 +0000
by Scottbags
hylux wrote:I think the OP by Tone raises a good point about dealers delivery but also check them after a service. I have had them drop them to 30 psi. Probably by an apprentice told so for cars.
Everyone will run different pressure depending on tyres, suspension, weight, roads you drive on etc. But you need to regularly check and find your sweet spot. In the last 4 utes I've had they were all different


I agree with finding the sweet spot.

Now I don't want to get into the nitrogen filling debate, but please remember if you have your tyres filled with regular air, they are loosing pressure right now through permeation - that is, O2 escaping through the rubber. I have had to do too many studies on this....

Just make sure to check your pressures at regular intervals.

Re: Tyre pressure

PostPosted: Tue, 14 Feb 2017 5:56 +0000
by creaky
Scott,

At what rate does air (22%O2) permeate relative to N2 ? Is it a significant increase in pressure loss from, say, a 32in tyre on 18in rim would he loss of 1 psi occur over 4 months with N2 rather than 3 months with air ? All else being equal of course.

Re: Tyre pressure

PostPosted: Wed, 15 Feb 2017 11:10 +0000
by Gulfstream8
creaky wrote:Scott,

At what rate does air (22%O2) permeate relative to N2 ? Is it a significant increase in pressure loss from, say, a 32in tyre on 18in rim would he loss of 1 psi occur over 4 months with N2 rather than 3 months with air ? All else being equal of course.


Unfortunately Creaky Nitrogen in Vehicle Tyres is a Scam and just another money making exercise - bit like a Hylcone ! We use it in Aviation Tyres for a number of reasons but none are applicable to the rest of us at sea level . Yes admittedly they do use it in "Race Car Tyres" but the advantages are so minimal and we are taking about 300klm "Race Cars" looking for any possible advantage with tyres that have massive forces applied to them in racing conditions.

Edit
As for Nirtrogen Vs Comperssor Air for tyre permeation or "loss of tyre pressure" through the tyre itself it's not mathematically or scientifically possible to show any significant difference! Nitrogen already makes up 78% of the air we breath and what goes into the tyre via a compressor. A nitrogen molecule is 300 picometers and oxygen is 292 picometers - a difference of 2.7%! Even if one still does not believe the science this has been proven in a controlled test where over a 15 week period no difference in pressure was found and it actually took a year before they found a difference of only 1.5 psi. At only 8 picometers bigger the Nitrogen molecule will not make any significant difference to "Permeation" through the Tyre. Other false statements are "Nitorengen does not expand" - this is rubbish too as all gases expand with heat. Please feel free to watch the video below where John runs through some basic science facts busting Nitrogen in tyres Myths.

Here is a great video by an "Actual Engineer" on the Top 10 reasons why
"Nitrogen in Car Tyres is absolute rubbish"
https://www.youtube.com/watch?v=bCnWvMleVD0

Re: Tyre pressure

PostPosted: Wed, 15 Feb 2017 12:04 +0000
by creaky
That's my understanding too Gulfstream but I am interested in what Scott's studies have shown.

Re: Tyre pressure

PostPosted: Wed, 15 Feb 2017 5:01 +0000
by Scottbags
Creaky, I mostly agree with Gulfstream that Nitrogen in road going tyres is a massive toss.

A 13.7kPa drop per month (sedan tyres, wheel material is not a contributing factor) is accepted in our industry.
However, if we all drove around in temperature controlled environments we could consider 'all else being equal', but we don't, and our studies show that ambient temps have a far greater impact on tyre pressure than what you choose to fill them with.

Re: Tyre pressure

PostPosted: Fri, 03 Mar 2017 7:51 +0000
by dazza609
What would you recommend running If my Hilux is currently weighing 1500kg over the rear axle and 1250kg over the front?

At the moment I am running 44psi in the rear which is the max the the tyres that are on the Toyota alloys I got second hand.

Re: Tyre pressure

PostPosted: Fri, 03 Mar 2017 9:25 +0000
by fracturedranga
Look up the 4psi rule. Its a pretty reliable way to work out your pressures

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 7:01 +0000
by martynvella
fracturedranga wrote:Look up the 4psi rule. Its a pretty reliable way to work out your pressures


Excellent statement, but it wont work with nitrogen in the tyres lol.
Nitrogen's biggest advantage is it does not expand with heat, so on haul trucks makes a difference but even then no site I have worked on actually uses it.
Also, how do you get all the air out of your tyre? even deflated it still has one bar in it and another two bar is added as nitrogen, leaving 33% air in there.
If it is only the oxy that is escaping then topping up with air will eventually leave almost no oxy in the tyre as it has all escaped over time trapping the other gasses in the tyre. In my opinion, not worth the expense.

Anyway lets get back on topic,
When I got my hilux new in 2012 it had 40 psi and I reduced it to the 29 psi in the book.
Every time I got it back from a service it was back to 40, I gave up letting it down as it did mainly town driving.
Those original tyres did 109k before I got sick of waiting for them to wear out so I could get a set of KO2s which were getting hard to get in those days. The old tyres just passed an inspection for an ATM upgrade on my trailer.

Don't know how long they would have lasted with 29 psi, but I have never had a set of tyres last more than 80k before on anything.

AND that was with air in them.

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 8:24 +0000
by Gipsy
Martin, I use 40psi because lower pressure causes my tyres to wear on the sides, also towing most of the time so need the extra psi. Wow! Hope I can get that mileage from mine oem bridgestone on my 2013 sr5

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 8:32 +0000
by martynvella
Gipsy wrote:Martin, I use 40psi because lower pressure causes my tyres to wear on the sides, also towing most of the time so need the extra psi. Wow! Hope I can get that mileage from mine oem bridgestone on my 2013 sr5


I think the milage I got out of them is a fair indication that I didn't have enough fun in the car as I was hoping to, trying to rectify that with this set.

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 8:56 +0000
by Gipsy
:lol: yep fun is in the eye of the beholder :lol: different strokes for different folks! I didn't buy my truck to destroy it in the bush but I understand those who do! I bought mine because it tows great, and far better than the old 80 series 1hdt. Couldn't afford the 200 series but the lux does all I want and more, never used 4x4 but glad l have it if I need it. Especially when sent to a van site and sank to the axles, shoved it in fourby and kept on going with 2.5tonne on the back!

Oops! Ventured off topic for a spell there, hope I didn't upset the thought police!

Back on topic! The 40 psi didn't hurt my truck in axle deep slush when I needed fourby!

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 10:01 +0000
by Rocket55
Oops, no need to be smart....

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 10:06 +0000
by Gipsy
Yup! General discussion again... Damn!

Re: Tyre pressure

PostPosted: Sat, 04 Mar 2017 3:59 +0000
by gjn
hylux wrote:Been running 40psi for years, great handling, great tyre wear and great watching the wifes boobs bouncing


Dash Cam???