Excessive tyre pressure from tyre shop.

Wheels, Suspension, Brakes & Tyres questions and answers

Moderators: timk, Stu, zombie, Andrew, -alex, miata

User avatar
Steampunk
Speed Racer
Posts: 4670
Joined: Wed Oct 10, 2007 9:16 am
Vehicle: NA6
Location: Southside of Breeze-bane

Excessive tyre pressure from tyre shop.

Postby Steampunk » Mon Jan 17, 2011 6:17 pm

Without going into a rant, can someone give me an explanation as to why tyre shops pump the tyres to some ridiculous 40+psi?
In short, I checked the pressures of my new tyres and they were 46psi warm, and 45psi cold.

I've gone through big names like Bob Jane & Beaurepaires, and smaller, private shops, and they have, almost all, done the same. The only exception being one small shop near my place, well-known to REALLY know what they are doing.

The only reasoning I can think of is that they do it because it enhances the difference between old and new.
Any other suggestions?
Image

manga_blue
Forum Guru
Posts: 4897
Joined: Mon Apr 24, 2006 7:27 pm
Vehicle: NA8
Location: Moruya, NSW

Re: Excessive tyre pressure from tyre shop.

Postby manga_blue » Mon Jan 17, 2011 6:24 pm

Cos they're slack. They like to pump them up to 40 to make sure the bead seats fully on the rim then they should back off the pressure to what suits the car, but they don't.

I've got a very seedy looking tyre shop at Moruya. Grant has done two sets for me there and they've all come back at exactly 30psi. I was shocked, I hadn't even asked him.
’95 NA8

User avatar
Steampunk
Speed Racer
Posts: 4670
Joined: Wed Oct 10, 2007 9:16 am
Vehicle: NA6
Location: Southside of Breeze-bane

Re: Excessive tyre pressure from tyre shop.

Postby Steampunk » Mon Jan 17, 2011 6:42 pm

Ah ok, so they pump it up high so the tyre stretches and conforms to the wheel as much as possible, and they can't be f%#ked checking the pressure after the car has been dropped?
Gotcha, makes sense. Thanks Phil.
Image

project.r.racing
Speed Racer
Posts: 3722
Joined: Sun Jan 18, 2009 10:16 pm
Vehicle: Non MX-5
Location: Glasshouse Mountains, QLD

Re: Excessive tyre pressure from tyre shop.

Postby project.r.racing » Mon Jan 17, 2011 7:43 pm

yeah they just forget sometimes.
depends on the tyre also, as prefences of the fitter will mean they put in extra psi.

User avatar
Garry
Speed Racer
Posts: 3481
Joined: Sun Apr 27, 2003 11:00 am
Vehicle: NB SP
Location: God's Country
Contact:

Re: Excessive tyre pressure from tyre shop.

Postby Garry » Tue Jan 18, 2011 11:13 am

I dont think I have ever had anywhere near the correct pressure in my tyres after I've had a new set fitted. They are always over inflated and quite often over the maximum pressure stamped on the tyre.
Shiney black one with added red bits. Member of the fart club. Now with extra doof and Sunlong. - deceased and gone to heaven

rascal
Racing Driver
Posts: 1770
Joined: Fri May 16, 2008 1:39 pm
Vehicle: NB8A
Location: FarSE Melbourne

Re: Excessive tyre pressure from tyre shop.

Postby rascal » Tue Jan 18, 2011 12:28 pm

And you'll probably find the wheel nuts are on to 900000 Nm as well, as they cant be bothered torquing them properly and just rattle them on using the shop rattle gun

User avatar
sliq
Speed Racer
Posts: 3414
Joined: Sat Jan 13, 2007 12:33 am
Vehicle: ND - 2 GT
Location: Sydney
Contact:

Re: Excessive tyre pressure from tyre shop.

Postby sliq » Tue Jan 18, 2011 12:56 pm

i'm currently in the process of having my tyre shop on. was not happy with the tyres, and with their service. got a telephone call from the tyrepower general manager of NSW yesterday, telling me he'll get to the bottom of things. so i know how you feel :evil: :evil: :evil:
i can't brain today.. i have the dumb..

User avatar
de Bounce
Racing Driver
Posts: 1091
Joined: Thu Feb 12, 2009 5:19 pm
Vehicle: NC
Location: Northern Burbs - Melbourne

Re: Excessive tyre pressure from tyre shop.

Postby de Bounce » Tue Jan 18, 2011 1:24 pm

I must be lucky
Over the years I have had a number of tyres fitted to a range of vehicles.
Most are supplied with between 32 to 34psi or the tyre fitter will ask what pressure I want and sets it accordingly.
Wheel nuts are a bit of hit and miss, some use a rattle gun, some use a brace and I have actually seen one use a torque wrench :shock:

If I notice they use a rattle gun to tighten the nuts, I'll ask the fitter to tighten mine with a brace.

The tyre dealer I currently use is happy to comply with my requests, therefore I will continue to use him whenever I can.
2011 NC2 PRHT SE in Dolphin Grey
2001 NB8B in Crystal Blue - Sold :(
Motorkhana Video

phaedo
Driver
Posts: 62
Joined: Sun Jan 28, 2007 1:40 am
Vehicle: ND - 2 GT
Location: Northern Beaches

Re: Excessive tyre pressure from tyre shop.

Postby phaedo » Tue Jan 18, 2011 6:25 pm

Another thing is they don't tend to use a guage in the first place, just inflate until full.

User avatar
de Bounce
Racing Driver
Posts: 1091
Joined: Thu Feb 12, 2009 5:19 pm
Vehicle: NC
Location: Northern Burbs - Melbourne

Re: Excessive tyre pressure from tyre shop.

Postby de Bounce » Tue Jan 18, 2011 7:02 pm

phaedo wrote:Another thing is they don't tend to use a guage in the first place, just inflate until full.

Most tyre mounting machines have the inflation hose and gauge as an integral part of the machine.
2011 NC2 PRHT SE in Dolphin Grey
2001 NB8B in Crystal Blue - Sold :(
Motorkhana Video

User avatar
Okibi
Speed Racer
Posts: 10901
Joined: Thu Aug 21, 2003 11:00 am
Vehicle: NB SE
Location: Perth, Western Australia
Contact:

Re: Excessive tyre pressure from tyre shop.

Postby Okibi » Tue Jan 18, 2011 9:08 pm

I've never had this issue. :mrgreen:
If you had access to a car like this, would you take it back right away? Neither would I.

User avatar
ForceMajeure
Fast Driver
Posts: 218
Joined: Tue Dec 14, 2010 9:46 pm
Vehicle: NB8A

Re: Excessive tyre pressure from tyre shop.

Postby ForceMajeure » Wed Jan 19, 2011 4:20 pm

Had my new wheels put on the other day and yep, 40psi i got them back at, plus one wheel has 70 grams of weight that are about 6 inches long!

I also now have massive vibration on the highway which has me wondering if they balanced the tyres correctly or its because they rotated them, or even worse my new wheel/s are not quite round.

Im also lacking hub centric rings which ive now ordered in the hope of making things better.

Sailor
Racing Driver
Posts: 1064
Joined: Wed Jun 24, 2009 5:49 pm
Vehicle: NC
Location: Southie...NOT from " the Shire " :/.

Re: Excessive tyre pressure from tyre shop.

Postby Sailor » Wed Jan 19, 2011 6:10 pm

It´s done to ensure that the tyre fully seats on the rim.
If you check you´ll probably see that your manual recommends checking tyre every day or at least each week.
In any case it´s a no brainer, chck your tyre pressures with your own, reliable guage regularly and especially after anyone has fitted tyres or serviced your car, Most use inaccurate guages or dont give a rats arse
Rob


05 NCLE, Cosworth SC,PF01,Ohlins,Selby,GWR exh
"We're only given a tiny spark of madness.We mustn't lose it"(Robin Williams)

deviant
Racing Driver
Posts: 1717
Joined: Thu Apr 15, 2010 7:23 pm
Vehicle: NB8B
Location: Rockingham - Western Australia

Re: Excessive tyre pressure from tyre shop.

Postby deviant » Wed Jan 19, 2011 6:20 pm

de Bounce wrote:I must be lucky
Over the years I have had a number of tyres fitted to a range of vehicles.
Most are supplied with between 32 to 34psi or the tyre fitter will ask what pressure I want and sets it accordingly.
Wheel nuts are a bit of hit and miss, some use a rattle gun, some use a brace and I have actually seen one use a torque wrench :shock:

If I notice they use a rattle gun to tighten the nuts, I'll ask the fitter to tighten mine with a brace.

The tyre dealer I currently use is happy to comply with my requests, therefore I will continue to use him whenever I can.


I have seen them use torque wrenches before....after using the rattle gun to do the nuts up. So they rattle them up tight and *click* goes the torque wrench. They assume because it has gone click that the torque is correct when in fact it is way over.

My local Bob Jane and Ian Diffen have both treated me well with service and price and done things correctly.

Besides poor education or laziness there is another reason for over tightening things and over inflating tyres. How many 'normal' motorists do you know that go and check their wheel nuts and tyre pressure once a week? Once a month? Once a year? Some people are dense enough to never check these things and then go back to the last workshop they used full of complaints when their tyres look a bit flat in 6 months or they lost a wheel after not checking for 2 years.

Talking of stupid people. Last summer I was on the freeway when a Mazda 3 overtook me.......on a space saver!! :shock: Of course a short distance later the tyre failed in spectacular fashion, I should imagine it was only pure luck or the cars inbuilt electronic aids that kept the car on the road. I am amazed that someone could be stupid enough to ignore the warnings on the wheel, tyre, handbook etc and drive a distance on the freeway at a speed far higher than the tyre is rated for.

User avatar
Guran
Speed Racer
Posts: 3754
Joined: Sun Feb 15, 2009 6:42 pm
Vehicle: ND - 1.5
Location: Albion Park NSW
Contact:

Re: Excessive tyre pressure from tyre shop.

Postby Guran » Sat Feb 12, 2011 7:29 am

True to form, my new set of Adrenalins were at 46psi when I got home from the tyre shop :evil: . The ride quality was aweful. Dropped them all down to 28psi. Much better! :D
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25


Return to “MX5 Wheels, Suspension, Brakes & Tyres”

Who is online

Users browsing this forum: No registered users and 76 guests