Word of Caution - Tyre Pressures

[Snoo]

Got myself a new electric tyre pump recently which I've been using and have been very happy with it on my cars. On the weekend I picked up a tyre pressure gauge. Popped my pump on and pumped my tyres to 40psi on the pump gauge as normal. Checked it with the new gauge, gauge reads 25PSi! So which is wrong? Borrowed a pump from my father and that told my my pressure was just over 30psi... 3 quite different readings. So I'm about to hunt down a decent tyre pressure gauge to use that I can trust.

tl:dr Get yourself a decent tyre pressure gauge and don't trust cheap gauges or pump readouts.

 

[P4ddy]

I have a twin cylinder foot pump on my motorbikes & mtb's. I had a handling issue at one point & needed an accurate pressure so I went to Sainsbury's to use their 'FREE' air, & my pump was spot on with the Sainsbury's one. I'm assuming public use pumped have to be regularly calibrated so that was good enough for me. So I'd try that, you'll have one that's got to be correct

 

[Snoo]

Used to use Sainsbury but it's always so busy on the air. It's probably a good shout to compare with any gauge I use and understand the difference though.

I used to have a good one for my motorcycle as a few PSi off and it was noticeable.

 

[Gran]

thanks for the tip.
the tyre pressures stated on the doorframe are a lot lower than 40psi, and if I set my tyres at the recommended pressure, every single person in every single carpark tells me I have flat tyres. Its hot over here so I set them at around 36psi - glad to hear some reinforcement!
(Also agree with the discrepancy seen between different gauges)

 

[Richard Fox]

Whenever I pump my tyres up I always check afterwards with a tyre pressure gauge just to be sure as most of the electric pumps I've used in the passed have always been very inaccurate!

 

[robert norton]

All gauges drift out of calibration. Calibration is needed to correct any wear & tear on pivots, springs etc. Any knock, temperature change, humidity change, and internal friction can cause reading errors.
Probably the most robust and reliable measuring gauge is the old fashioned sliding quill. Just keep it clean and dry.
Robertn

 

[Kenzie (Mary Poppins)]

I'm lucky run mineral 28psi check 1stvthing in a morning both minevread the same

 

[Gedouardo]

I've just had some 17'2 put on and apparently the Autodata info said 40/45 psi

 

[Highway Dave]

Commercial by any chance, also is the 40/45 max

 

[Gedouardo]

Commercial by any chance, also is the 40/45 max

SUV designation 51psi max

 

[Highway Dave]

SUV designation 51psi max

Depends on profile as well I suppose, the lower the profile the higher the psi ( usually)
I run 19x245x45 and they love 38/40psi

 

[Gedouardo]

Depends on profile as well I suppose, the lower the profile the higher the psi ( usually)
I run 19x245x45 and they love 38/40psi

215/60 R17
My 19's got a crack on my journey to work (175 miles) on Sunday night. I got a cheap pair of OEM 17's from a local.

 

[Cato Fong]

Got myself a new electric tyre pump recently which I've been using and have been very happy with it on my cars. On the weekend I picked up a tyre pressure gauge. Popped my pump on and pumped my tyres to 40psi on the pump gauge as normal. Checked it with the new gauge, gauge reads 25PSi! So which is wrong? Borrowed a pump from my father and that told my my pressure was just over 30psi... 3 quite different readings. So I'm about to hunt down a decent tyre pressure gauge to use that I can trust.

tl:dr Get yourself a decent tyre pressure gauge and don't trust cheap gauges or pump readouts.

FWIW some time ago Auto Express tested tyre pressure gauges and recommended the Draper 69923 TPG101 which is a small mechanical dial type. I find the traditional pencil type can stick and battery ones are no good if they go flat/corrode. FWIW I've got a 20 year old Hilka tyre pump/torch whose gauge is bang on but other small 12 volt tyre pumps I have bought since then are useless. If you want a 12 volt pump/gauge it might be worth getting one of the OE Honda, Vauxhall, etc, ones that are provided with a can of sealant from a scrapyard since they should be decent quality. Don't forget to check the skinny temporary spare tyre which requires a high pressure to work properly.

 

[Mark76e]

Depends on profile as well I suppose, the lower the profile the higher the psi ( usually)
I run 19x245x45 and they love 38/40psi

I'm on the same sizes but at 42psi.

 

[Highway Dave]

215/60 R17
My 19's got a crack on my journey to work (175 miles) on Sunday night. I got a cheap pair of OEM 17's from a local.

If suv rated then 49 sounds ok, car tyres of same size may need less——-

Edited , meant to say 40/45. Not 49 ( fat fingers small phone)

 

[Lize]

Probably the most robust and reliable measuring gauge is the old fashioned sliding quill. Just keep it clean and dry.

I agree, the pencil type ones are good and stay accurate as opposed to dial ones which are often wrong from day 1.

 

[Carolina]

Just tested mine and all were at 32psi ish.

Felt like I was drifting every time I went round a bend! Mind you, it doesn't take much for me to feel like that anyway!

Now at 40psi, much better.

 

[Snoo]

Lidl have their digital tyre pressure gauges in store this week for under £9.
Well worth it

 

[Londonglide]

I managed to get a SteelMate TP70 TPMS kit from FB for a knock down price.. Sensors are a bit bulky, but the controller just plugs into the lighter socket. Will see how long it lasts. have a set on my motorcycle, which have been very reliable, but I'm more likely to loose the sensor on the Elgrand, so a cheap plaything, and the pressure measurement accuracy is pretty good