Space Saver Tyre Pressure?

[rbz5416]

Washing the car the day before it's MOT I found a bulge in the sidewall of one of the tyres. Annoying as it's only done a few thousand miles since fitted. Stuck the spare on which I thought was supposed to be full size but it's not. Tyres are 215/45/16 & the spare is a 185/60/15! So can't get it MOT'd with a mismatched tyre. Now got to order in a replacement as no one carries this size in stock.

Pressure in the spare is low but I can't find any reference to what it should be, other than vague "Refer to label" statement on the yellow label! While I hunt for the manual does anyone know what the pressure should be?

Also anyone else with an SEL with the 16" wheels able to confirm that they're spare is also 15"?

[iichel]

about 2-2.5 bars should be fine for this size

[rbz5416]

Thanks, I guessed at 2.2 but I suppose not that critical in the short term.

But I was surprised at the difference in diameter. There should be theoretically little difference between the two but the 15" measures 25mm/1" more.

[iichel]

that's interesting since these are both factory tire sizes.

[SRGTD]

Washing the car the day before it's MOT I found a bulge in the sidewall of one of the tyres. Annoying as it's only done a few thousand miles since fitted. Stuck the spare on which I thought was supposed to be full size but it's not. Tyres are 215/45/16 & the spare is a 185/60/15! So can't get it MOT'd with a mismatched tyre. Now got to order in a replacement as no one carries this size in stock.

Pressure in the spare is low but I can't find any reference to what it should be, other than vague "Refer to label" statement on the yellow label! While I hunt for the manual does anyone know what the pressure should be?

Also anyone else with an SEL with the 16" wheels able to confirm that they're spare is also 15"?

Tyre pressure for the spare tyre should be shown on the tyre pressure label on the inside of your car’s fuel filler flap.

This is the tyre pressure sticker that was on my previous Polo - a GTI. Pressure is likely to be different for your car as the wheels / tyres are a different size. The space saver spare tyre pressure is at the bottom of the sticker;

IMG_1278.jpeg (79.94 KiB) Viewed 2109 times

[rbz5416]

Not on mine, checked there first.

[SRGTD]

Not on mine, checked there first.

Also check the lower section of the driver’s side B pillar; that’s the location of the sticker in the AW / BZ Polo.

Try an internet search on ‘VW Tyre Pressure Sticker’ and you’ll see from the images that the tyre pressure for a VW space saver spare irrespective of car or space saver size seems to be 4.2 bar / 60-61 psi.

60-61 psi sounds very high but it’s probably that high as I dare say few owners regularly check the tyre pressure of the space saver spare, and over time there’s a good chance it’ll lose some pressure. If it’s inflated to 60/61 psi then it reduces the risk of it having lost too much air over time to render it unusable when it’s needed. If it has, then if you carry a 12v portable mini tyre inflator / compressor in the boot of your car and a tyre pressure gauge, you’ll always have the means to re-inflate it if necessary.

[RUM4MO]

I'd stay away from using 61psi on "smaller than fitted spare tyre", I have noted down 40 > 42psi for the spare on my wife's 2015 VW Polo 1.2TSI 110PS SEL, the 61psi is only used on the proper space saver type tyres, ie the really slip ones with very little thread depth.

That size of spare is correct for that car.

Edited:- changed the incorrect "I'm" to the correct "I'd".

Ans yes, VW didn't seem to bother to include the pressure for the spare tyre on the pressures label on the inside of the filler cover.

[rbz5416]

B pillar label only references the TPMS, no pressures there.

I guess VW were just too cheap to provide the correct size spare for the SEL (16") & probably the GTI (17") too. The 185/60/15 being standard for the rest of the range, there was no need for additional pressures as it would be a like-for-like replacement using default pressure.

I agree that 60 PSI would be way excessive.

[amer6R]

What does the tire say, what is the maximum inflation pressure?

[RUM4MO]

Maybe I should have been a bit clearer when I said what pressure to use with that "smaller than fitted" spare wheel, the pressure I gave would be a safe storage pressure, ie to get checked every year at service time, and when actually needing to use that spare wheel, ideally only on the rear of the car, adjust the pressure down to what you normally use at that point on the car.

I'd guess, just guess, that where the front discs are 288mm then the supplied spare wheel must be a 15" as a minimum, if the smaller front discs are fitted, then a 14" spare wheel with the appropriate tyre would be okay. Going back to when my daughter had a 1.4 86PS Ibiza SC, it came with 17" alloys and a 14" steel spare wheel - as that was adequate for that car with its 256mm front discs.

Edit:- I use 15" alloys on my wife's 2015 VW Polo 1.2TSI 110PS SEL in Winter time, and the pressures that I use are the same or slightly higher, by maybe 1.5psi or 2.5psi - measured at 15C, as the best plan is to raise the checking tyre pressure slightly so that they are closer to being correct at times of lower temperatures - I think.

[rbz5416]

Edit:- I use 15" alloys on my wife's 2015 VW Polo 1.2TSI 110PS SEL in Winter time

Just out of curiosity, do you notice any appreciable difference in ride quality on 15" rims? I'd really like to soften the ride on mine & had thought about dropping down to the 60 profile on 15", hoping that more sidewall would equal a less harsh ride. But it's an expensive experiment!

[RUM4MO]

Just out of curiosity, do you notice any appreciable difference in ride quality on 15" rims? I'd really like to soften the ride on mine & had thought about dropping down to the 60 profile on 15", hoping that more sidewall would equal a less harsh ride. But it's an expensive experiment!

To be honest, not really, I don't find the combination of that size and brand (Conti) of wheel and tyre must harsher than the 15" wheel and Michelin Alpin tyres, but, I did notice a huge difference on my wife's previous car, a 2002 VW Polo 1.4 75PS when changing from 15" "low profile" Summer tyres in the original brand and Michelin Exaltos to 14" Winter tyres, again Michelin Alpins. I've forgotten what the 15" and 14" tyres used on that car were, but the Summer tyres were standard fit size but the Winter tyres were a size wider than the normal 14" standard fit - which means that the winter tyres would have had a smaller than standard fit side wall - and I should not have really noticed that improvement between Summer and Winter tyres, but I did!

Edit:- when I chose the 14" Winter tyres/wheels for the 2002 VW Polo, I'll admit that I was aiming to retain a slightly wider tyre for Winter use, I suppose vanity over function, but these Winter tyres in that width worked very well in nasty Winter weather up here in Scotland. When picking a Winter tyre/wheel size for this 2015 VW Polo 1.2TSI 110PS SEL, as we are now both retired, I just went for the narrower width which is same as standard fit on some Polos, so that we would get the supposedly best grip in Winter.

[rbz5416]

To be honest, not really

OK, thanks.