Low Tyre pressures

Hey

I have some Rays wheels , I only use the Supra the weekend so she sits up for about 5-6 days at a time; I need to top up the pressure on each tyre weekly, on average the Tyre pressures generally drop 3-4 psi all round.

I presume this is not normal, I have just ordered some new rays valve stem's to re-valve the wheels. Anything else I can check. which may be causing it?

Are they one piece rims or split?

Are they one piece rims or split?

Volk GTC, 2 piece rim

I never took them apart or had them apart, I bought them new from Volk. Still as per factory assemble

My plan is

New Valve stems (VOLK authentic from a Volk authorised dealer)

New Tyres

If this doesnt work it is the Rim leaking is the next question? What time period should you see a pressure drop over, check pressures monthly?

Where are you checking them, have you factored in that you may be reading them incorrectly?

I.e.

You drive to the garage and put 32psi in, you drive home and park your car, and you check it the next day - and its only got 30psi.

Your tyres arent going down, they have just cooled down from the drive - also, id expect them to be less than just a 2psi loss, due to the weather being colder.

I run a TPMS on my motorbike, which is wonderful by the way.

It tells me what pressure AND temperature my tyres are at, I can go from having 30psi on a cold morning right up to 38psi if im hammering the motorway.

If i check my tyres incorrectly, can you imagine the confusion id have?

Mobletron is the TPMS I use, avaliable for cars too, comes in at £99.00inc vat for a motorbike, slightly more for a car - very accurate and updates every 5 seconds or so.

Useful for punctures too, I can be hurtling down the motorway, collect a puncture and not know until im dead. Now I can pull over, as it flashes to warn you.

http://www.mobiletron.com.tw/b_eng_products_view.asp?FkindNo=F000004&SkindNo=S000030&Pd_Id=3580

FYI

I use the same Texaco garage, 5 min drive away; it has the digital unit you set the pressure etc. I definitely can feel the tyres are Low , she normally always shows roughly 28 psi and if I leave it longer (if I was on holidays for example) she can go as low as 25/26psi mark.

Some tyres are worse than others but it is a consistent test,it is like this about 1.5 years now; just my usual routine If I want to drive her, straight to the garage first for a pressure top up; pain in the ass so I bit the bullet and got all new valve stems on route ( I hope this fixes it!)

http://www.mobiletron.com.tw/b_eng_products_view.asp?FkindNo=F000004&SkindNo=S000030&Pd_Id=3580

 

FYI

thanks!

I never looked into these before because they all where valve type units ; band type is what I need!

Colder weather makes the pressure go down too don't forget

thanks!

 

I never looked into these before because they all where valve type units ; band type is what I need!

Yes, i use band types, they are best.

Yes, i use band types, they are best.

At this stage you would think you could get something that runs via your smart phone

At this stage you would think you could get something that runs via your smart phone

I prefer a dash mount, its always there, I know when my tyres are warm, and I'll always see it, so when I get a puncture, I know ASAP.

Battery was low on my phone, Phone left at home, left it in gym bag in the boot, distraction to use, using phone whilst driving 3 points, killing other road users.

Too many downsides

If the wheels have never been split and are relatively new, and all four are losing pressure, it's probably unlikely that the rims themselves will be leaking. Easiest way to check is to take one off and squirt some soapy water around the split rim bolts (front and back), around the join in the barrel/basket and around the valve. If no bubbles, I'd squirt some around where the tyre meets the wheel (front and back again), it's possible that they just need a bit of bead seal.

Hope it's not leaking rims bud!

Volk GTC, 2 piece rim

 

I never took them apart or had them apart, I bought them new from Volk. Still as per factory assemble

 

My plan is

 

New Valve stems (VOLK authentic from a Volk authorised dealer)

New Tyres

 

If this doesnt work it is the Rim leaking is the next question? What time period should you see a pressure drop over, check pressures monthly?

They wont leak as its only the centre section that unbolts, perhaps your losing air from around the

bead or the valve.

If fitting new valves doesn't fix them get the tyres popped off and the rim wells where the tyre bead fits cleaned,

then some tyre sealer can be used on the rim to help seal them when the tyres go back on

They wont leak as its only the centre section that unbolts, perhaps your losing air from around the

bead or the valve.

If fitting new valves doesn't fix them get the tyres popped off and the rim wells where the tyre bead fits cleaned,

then some tyre sealer can be used on the rim to help seal them when the tyres go back on

I was about to say that... Ish.

U can take the entire centre and be just left with a rim and inflated tyre with 2 piece... 3 piece however

I was about to say that... Ish.

U can take the entire centre and be just left with a rim and inflated tyre with 2 piece... 3 piece however

Depends on the 2 piece ( not arguing you in this instance ) But some are wheel face and basket with a detachable lip

Depends on the 2 piece ( not arguing you in this instance ) But some are wheel face and basket with a detachable lip

Yes agreed they do vary but the Volk GTC look like the outer rim is one piece with a detachable center

Cool , thanks ; hopefully the new valves will do the trick

I have stock Toyota 5 spoke alloys . . . . but have a couple that always leak slowly, like you describe (that's despite several new sets of tyres)

I just squirt in half a can of Tyre Sealant in each, and it fixes the problem !

Where are you checking them, have you factored in that you may be reading them incorrectly?

 

I.e.

 

You drive to the garage and put 32psi in, you drive home and park your car, and you check it the next day - and its only got 30psi.

 

Your tyres arent going down, they have just cooled down from the drive - also, id expect them to be less than just a 2psi loss, due to the weather being colder.

 

 

 

I run a TPMS on my motorbike, which is wonderful by the way.

It tells me what pressure AND temperature my tyres are at, I can go from having 30psi on a cold morning right up to 38psi if im hammering the motorway.

 

If i check my tyres incorrectly, can you imagine the confusion id have?

 

 

Mobletron is the TPMS I use, avaliable for cars too, comes in at £99.00inc vat for a motorbike, slightly more for a car - very accurate and updates every 5 seconds or so.

 

Useful for punctures too, I can be hurtling down the motorway, collect a puncture and not know until im dead. Now I can pull over, as it flashes to warn you.

Hi Purity

Where did you buy the TPMS from?

Cheers

Mark.

Did we ever find out if the valves fixed this?

IMO, driving a car before checking the pressures is not ideal. I have a compressor at home and a digital gauge to get the correct pressures when cold. As Purity says, the difference when hot and cold can be massive, also dangerous and can cause premature wear.

My rims are 3 piece, with Falken tyres, the pressure has never dropped from its cold reading, been 2 years going..

I have stock Toyota 5 spoke alloys . . . . but have a couple that always leak slowly, like you describe (that's despite several new sets of tyres)

 

I just squirt in half a can of Tyre Sealant in each, and it fixes the problem !

Shouldnt you only drive around 50 miles with tyre sealant? I've got the understanding that the tyres become unpredictable while sharp cornering and high speeds.....

the problem you have is common on all cars, you need the tyres taken off the rims and both the tyre and wheel cleaned around the bead area, once cleaned a solution called bead seal should then be applied to the wheel top and bottom then a light coating of tyre soap just to fit the tyre without ripping the bead, this will solve the issue, it is also best to check your tyre pressures while the tyres are cold as driving can cause the pressure to increase anywhere from 2-8 psi depending on brand of tyre and road condition, a bead leak will cause the tyre to loose approx 15-20psi over a period of 2-3weeks in an extreme case it will only take a week or 2days,

Shouldnt you only drive around 50 miles with tyre sealant? I've got the understanding that the tyres become unpredictable while sharp cornering and high speeds.....

That's if you have a puncture and use it to seal the hole