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Kiki Lala
29-08-2009, 09:05 PM
Hi i m very new into this motoring world.
so dont laugh at my silly question.

i was wondering how do u check the tyre pressure?How much of air to pump in & what pressure to use.

Recently i bought an instrument called tyre gauze?
how much should i pump the air in when the tyre is in used?

gary yap
29-08-2009, 09:30 PM
No such thing as silly question(tho it sounded silly :D )

The tyre pressure are stated as the drivers side door along the 'sill' of the chasis. Commonly I know of are between 200-220 depending what rim and tyre size you using.

Sentinel
29-08-2009, 09:35 PM
Kiki Lala, the amount of air to be pumped into your depends on the car make you are driving. In most cases, there are 2 places you can find how much air to pump into your tyres.

Open your front door, driver's side and you will normally see a sticker on the door frame. This table shows you like :

Front tyre : 175/15R-70
Rear tyre : 175/15R-70

(The other place is in your Owner's Manual and listed under TYRE).

These shows you the size of the tyres you should use on your car. The first number 175 means the width is 175mm, the second number 15R says the diameter of the tyre is 15 inch and 70, the third number is the height or thickness from the inside circumference to the outer circumference.

So, 205/17R-55 means width 205mm, 17 inch in diameter and 55mm thickness/profile, this is a wide tyre which is thin in profile. It is sometimes known as low profile tyre.

The table will also show you the amount of air to pump. For example :

Front : 30 PSI, this means pump in 30 pounds per sq inch. Just set the gauge at the air pum to 30PSI and pump. The tyre pump will stop automatically or the tik-tik-tik sound will slow down to a stop when your tyre pressure is 30PSI.

Normally the back tyres are of the same pressure. Only performance cars have different tyre pressures for front and back eg most Porsche cars have different size tyres for front and back and thus different air pressure. Most cars on the road are same tyres for front and back and thus same tyre pressures all around.

Sometimes you need to convert his 30 PSI to another number when the pumps are not in pounds per sq inch (PSI). I will research a bit on the conversion bit and post again.

expat1609
29-08-2009, 10:22 PM
Normally the back tyres are of the same pressure. Only performance cars have different tyre pressures for front and back eg most Porsche cars have different size tyres for front and back and thus different air pressure. Most cars on the road are same tyres for front and back and thus same tyre pressures all around.



see that in proton cars, front and back same, thought front should be more, due to the weight of the engine
toyota manual says so as well, front 220, back 210...confused indeed

tsela
30-08-2009, 07:14 AM
Hi i m very new into this motoring world.
so dont laugh at my silly question.

i was wondering how do u check the tyre pressure?How much of air to pump in & what pressure to use.

Recently i bought an instrument called tyre gauze?
how much should i pump the air in when the tyre is in used?


Tyre Pressure


How much?

Information inside vehicle manufacturerís manual
Information on driverís door inside frame or pillar
Information on petrol cap
May be same or different pressure for front and back tyres

How to check? (analog or digital gauge)

Hand-held type pressure gauge
Screw-onto-tyre type cap pressure gauge
Service station air pumpís pressure gauge

When to check?

When tyres are cold (e.g in the morning, or tyres not run for two hours, or run at low speed for less than 2km)
Monthly (air pressure can leak out)
Before long journey
Spare tyre too

How to convert?

1 standard atmospheric pressure atm atm = 1.01325 bar
1 bar = 100 kPa (kiloPascals) ≈ 14.50 psi (Pound per Square Inch)

bslee
31-08-2009, 06:15 PM
Its imperative that any car enthusiast should buy a hand held pressure gauge and keep it handy in the car. Its no rocket science how to use one. A good brand is by PCL. Air pumps at petrol station were'nt accurate but roughly there. Ain't sure about newer pump stations now but have a gauge to double check to be sure.
I bought one decades ago thats 10" long and perhaps an industry standard. Its handy all the while.

Kiki Lala
06-09-2009, 11:52 AM
So i just go to gas station & pump the air in till the click click sound stop?
At what air pressure should i put?
400?

CCY
06-09-2009, 12:33 PM
Hi i m very new into this motoring world.
so dont laugh at my silly question. No....not laughing but winking can o not...?


i was wondering how do u check the tyre pressure? Of course you have to have the right tool and poke at some right places where you can use to release extra gases.....


How much of air to pump in & what pressure to use.As much as you like since these different round thing can take from 28psi to 120psi.....


Recently i bought an instrument called tyre gauze

Wow....this new invention, tyre gauze , would be best use to patch some wounded tyre.....but tyre gauges are those round little thing again that is use to show how full is your round thing ...best doing it when it just wake up n cold....


how much should i pump the air in when the tyre is in used?Ah....it depends on how full , how empty , how small, how big ,how heavy your round thing is and it should not have any when not in use....

Ooooh ...Today is Sunday.....

tupai
06-09-2009, 12:40 PM
So i just go to gas station & pump the air in till the click click sound stop?
At what air pressure should i put?
400?


Ayam twying not to laugh..but u leally pum 400? :eek: u dwiving wat ah? petronas tanki truck ah? :p

Yang Belum pum 400psi latotupai :p

mick123
10-09-2009, 08:04 AM
So i just go to gas station & pump the air in till the click click sound stop?
At what air pressure should i put?
400?

not sure if i missed anything but what type of car are you driving?

for a standard sedan car, it would be ok to pump 30psi (pounds per square inch) and this is equivalent to about 210kPa, the 2 units you will most commonly see on the gauge. once the pressure on the gauge is set, you got that right, pump until the click-click or ding-ding sound stops.

SUVs, MPVs, 4WD and those on low profile tyres may require higher pressures than normal cars and factory fitted tyre sizes.

i would assume your 400 is in kPa. i think this is for smaller trucks. for those big trucks, they put in about 600kPa.

like others have said, the best place for the recommended tyre pressure should be stated on the car's manual or a sticker at the side of the door.



........all that said, remember to check your tyres and the pressure regularly. this would help safe a little bit of fuel and your tyres would last longer. I do mine once a month.

kwchang
10-09-2009, 09:07 AM
It is amazing that after 10+ days nobody (except Mick) gave Kiki a simple layman guide to pump her tyres! And also Kiki never came back to say something as well ... I wonder if her tyres blew up on the highway, running at 400K pressure?!!

To make things simple, any car (even an Innova like mine) would just need 220K pressure all round as a simple guide. For more refined needs, you need to refer to your user manual.

Now, remember, this is the pressure when the tyres are cold - ie before you run for hours on the highway. You see, after running for hours on the highway, the tyre pressure goes up (naturally) to even 300K due to friction on the road. Why I am saying this is that you should not check the tyre pressure immediately after driving to Singapore for example because if you then set the gauge (note - not "gauze") to 220K, you will end up with underinflated tyres after it cooled down.

One important note - when you take delivery of a NEW car, you may be surprised to find that the tyres are actually inflated to beyond 300K. I believe the assembly plants do this knowing that the cars may need to stand unused in the storage and showroom, so the new customer isn't going to get home with uninflated tyres. I know this for a fact when I went to pump up the tyres when I first took delivery of my new Innova - it was 315K on the digital pump reading! Maybe a fluke shot? No, I found the same thing when i checked the tyres of my sis-in-law's new Honda as well.

Actually, all car tyres are rated for pressures beyond 300K (but certainly NOT 400 la). By the way, cheap tyre guages are not reliable - it isbetter to depend on the pump at the petrol stations - provided you know how to set the right pressure before you pump. The digital pumps are the best - if yr tyre is over-inflated, it will reduce the pressure for you.

Final note on the ding-ding feedback from the air-pump at the petrol station - that applies to the old analog (dial) types. If you use the digital pumps, there is no sound and the pump will only make a sound (high pitch peep) when the pressure is correct - signal to stop pumping.