Tyre (Tire) Pressure

[puukao]

anyone say that when it's HOT, psi goes up.  not sure in car tires how much, but maybe it's a few psi.  i would go 2 psi under, due to the heat.

 

my point is....don't over inflate in the morning.  but i've never seen a car tire explode due to expanding because of the heat.

 

carry on....

[transam]

Many rides have a different PSI "advice" for loaded or unloaded. My Volvo estate was one. My ol' Vigo had the same advised 29 PSI all round loaded or unloaded.

 

Our small runaround has high-ish advised PSI for stock tyres but ours has trendy one inch bigger and wider  rims with lower profile and wider tyres where the ride is crap with the stock PSI, so I fooled around with the PSI to make the ride more acceptable, the PSI is now a lot lower.

 

My fun ride with way bigger tyres on the rear had 22 PSI in the rear and 35 in the front for street use...

[transam]

7 minutes ago, puukao said:

anyone say that when it's HOT, psi goes up.  not sure in car tires how much, but maybe it's a few psi.  i would go 2 psi under, due to the heat.

 

my point is....don't over inflate in the morning.  but i've never seen a car tire explode due to expanding because of the heat.

 

carry on....

The advised PSI is for cold tyres, this allows for tyre PSI rise when in use/hot..

[fredob43]

2 hours ago, transam said:

The advised PSI is for cold tyres, this allows for tyre PSI rise when in use/hot..

Correct. If anyone wants to know tire pressure can go up around 5/6psi when hot from Cold. My last lump had a temp/pressure gauge. On a run it would go up by around 8 to 10c and 5/6psi. Dependent on outside temp: and speed. That started to happen after a few read 1/2 km. So using your local garage to get a correct reading would be useless as they would have already gone up in pressure.

Edited February 3, 2019 by fredob43

[Lacessit]

18 hours ago, wgdanson said:

Was it stick shift or automatic. LOL

Gear shift was on the steering column. Bench seat, very few bucket seats. A bit cramped for a six-footer like me, but I managed.

[Lacessit]

On 2/2/2019 at 11:58 AM, bluesofa said:

I don't think blood pressure tends to be measured in psi, not sure about the units for peer pressure though.

It's measured in mm of mercury. mmHg is the abbreviation. Peer pressure is not something I've ever had any truck with.

[Lacessit]

On 2/2/2019 at 12:59 PM, JAG said:

I was yesterday the witness (rather too close for comfort) of an accident which was, I suspect, at least partly caused by the local habit of greatly overinflating car tyres. As I bimbled sedately in my old pick up into Chiang Rai (Dad's Taxi, on its way to transport Little Miss JAG from School to singing lessons - she is going to be a superstar you know) a brand new Fortuna came around the corner (a gentle bend) rather fast and rather wide. He must have braked hard and turned sharply, to steer back to his side of the road. The back slid out, and he went straight off the road, at a right angle, into a wall. The front end and bonnet were smashed in by the impact. I stopped, and with a couple of Thais must have opened the driver's door within about 30 seconds of the impact. He was sitting there, in shock, uninjured and holding his mobile phone in his right hand!

 

I wouldn't mind a bet, looking at how the Fortuna had reacted to his steering and braking, that his tyres were greatly overinflated.

 

Interestingly, despite the extensive damage to the front end, his airbags didn't deploy!

Possibly driving with his left hand and texting with his right hand on the phone contributed. Scientific studies have concluded while conversation is not too risky, texting while driving is the equivalent to having a BAC of 0.06 - 0.10 in one's system in terms of slowed reactions.

[wgdanson]

38 minutes ago, Lacessit said:

Possibly driving with his left hand and texting with his right hand on the phone contributed. Scientific studies have concluded while conversation is not too risky, texting while driving is the equivalent to having a BAC of 0.06 - 0.10 in one's system in terms of slowed reactions.

And of course, finding music on your phone, putting a destination into Google Maps, all just as dangerous. Luckily I have Google Assistant so just press that one button and say what I want.

[JAG]

2 hours ago, Lacessit said:

Possibly driving with his left hand and texting with his right hand on the phone contributed. Scientific studies have concluded while conversation is not too risky, texting while driving is the equivalent to having a BAC of 0.06 - 0.10 in one's system in terms of slowed reactions.

Almost certainly. However I was interested in how the vehicle behaved - the rear end definitely slid out quite dramatically.

[CanNot]

My one said 36 psi in the door all around, but I go a bit over by 2psi. I think I read it somewhere years ago and do it like that since then, no issue so far. 

What I recommend is when other people doing it for you always double check. I had situations after a tire change the pressure where all over the place on the 4 tires. ????

 

[JAS21]

7 hours ago, CanNot said:

My one said 36 psi in the door all around, but I go a bit over by 2psi. I think I read it somewhere years ago and do it like that since then, no issue so far. 

What I recommend is when other people doing it for you always double check. I had situations after a tire change the pressure where all over the place on the 4 tires. ????

 

Not another that knows better than the car designer ... anyway 70 posts now and the answer was supplied in post#2 ... ????

[HAKAPALITA]

10 hours ago, JAS21 said:

Not another that knows better than the car designer ... anyway 70 posts now and the answer was supplied in post#2 ... ????

Nothing changes, even the Fortuna got mentioned again for the Zillioth time.

[dreytom]

To know the correct psi for your tires, you can do the "chalk test".  There are Youtube vids that explain this method.

[transam]

16 hours ago, dreytom said:

To know the correct psi for your tires, you can do the "chalk test".  There are Youtube vids that explain this method.

I was at a Suzuki dealers Tuesday, whilst they were doing there thing on my car I wondered around the workshop looking at a couple of Swifts up on hoists, both were very smart with the tyres all nicely black "painted" buy the owners. Being up in the air I noticed the treads on both were road dust covered and the nice black paint was on the outer part of the tread, even on the fronts. This told me both cars had tyres well over pressured..????