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yeders
16-04-2018, 10:18 AM
Hi guys,

I had read somewhere that someone had confirmed (with an engineer) a different tyre size would work on 19 Phoenix wheels instead of the current stock size of 235/40/19?

Has anyone read this, as I am unable to find the post/details?

Thanks

2009fsi
16-04-2018, 11:30 AM
Yes. I have 245 40/19s Continental Sports contact 6s on my 206. It is legal for the rim size, according to JAX, confirmed in RTA regs. 245s are a common size to fit hold-ons, fords & a lot of other makes in Australia. Hence they are more readily available, more choice of makers & variants at significantly cheaper price per wheel than 235s.

There is an old thread in here somewhere in which the math of the difference to 235s was agonized over by the forum professors for a week. In short, when brand new, inflated to 38psi, the tyres will indicate just on 2kms higher at 100kph. That still leaves you 3kms under the real speed limit of 100kph because ADRs mandate manufacturers must adjust speedos to read 5% higher than your real speed. IE: You will still be 3kph below the actual speed limit at 100kph. Of course, as they wear, the difference becomes nothing.

I've also got a full size spare with 245 fitted. It fits about 12mm high in the wheel well, after trimming the intrusive bit of flat plastic trim across the rear of the wheel well. Purists have kittens about this but with the boot floor in place I'm yet to find anyone, including Skoda mechanics doing services, who even notice a difference. Better than the billy cart wheel Skoda supply as a spare, if you are a regular traveler.

dArK5HaD0w
16-04-2018, 02:51 PM
thanks for that @2009fsi.
tis good to know that 245s r an option to consider. as u pointed out - they are more common here and hence much cheaper thanks to the demand, in comparison on the 235s.

yeders
17-04-2018, 12:08 AM
Arrr!! Champion. Thanks for that!

One question - the inflation values, do you increase the PSI a little more than the inflation guide for the 235s? (tyres/load/front rear psi value)
If so, how much, or not at all?

2009fsi
23-04-2018, 11:11 AM
The tyre manufacturers recommended pressure for 245.40.19 Conti 6 on the car is 36-38psi. I use 37psi, have nice even tyre wear & very good steering feel & adhesion in all conditions. Under inflating risks wall damage on our uneven goat tracks, over the reverse potholes called speed humps etc.

ope126
16-10-2018, 07:07 PM
The tyre manufacturers recommended pressure for 245.40.19 Conti 6 on the car is 36-38psi. I use 37psi, have nice even tyre wear & very good steering feel & adhesion in all conditions. Under inflating risks wall damage on our uneven goat tracks, over the reverse potholes called speed humps etc.

How are the 245's going a few months on?
Might start looking into 245's for mine also!

ope126
19-10-2018, 03:51 PM
So it appears that the VW Passat Alltrack Wolfsburg Edition runs a 19x8 (Albertville) with 245/40R19 94W tyres.

I think there would be no issue with a change from 235 up to 245 still on the 8" rim.

Maybe VCDS can code for the different tyre size to cancel out any speedo error?

jdw
20-10-2018, 10:26 AM
Is anyone running 245/40/19 on a MK 7 Golf ? I have a new set of wheels 19 x 8.5 and was thinking of 245 for comfort. cost and stance reasons.

ope126
06-04-2019, 05:35 PM
So a little further digging revels the Passat (like my previous B8 had) comes with a full size spare, so no real issues there.

I would be interested to hear from other ŠKODA Superb owners with 19" wheels what their space saver tyre is?
Mine is a Continental T125/70R18 99M CST 17.

I too am / was considering the change to a 245/40R19 tyre as replacement, however one piece of advice I received from a Tyre Retailer was to check the spare and compare the dimensions (rolling circumference), as they seem to think that they should all be the same as any difference could throw out the car (drivetrain / Haldex) if driven for any extended amount of time. For example if faced with a puncture and then rolling on the space saver for another couple of hundred kms...

As the rolling circumference of the Continental T125/70R18 99M CST 17 is 78.2inch; 125/70R18 Tires (https://tiresize.com/tiresizes/125-70R18.htm)

Which doesn't even match the OEM 235/40R19 tyres rolling circumference of 82.9inch; 235/40R19 Tires (https://tiresize.com/tiresizes/235-40R19.htm)

So my question is, are the supplied space savers all 18" or should they also be 19"?

As now the theory of the Tyre Retailer most likely has no relevance based on the OEM items as described above.

Yes the 245's are cheaper and have an increased availability / variety of patterns, but I am wondering if it is the right choice?

What I do know is that the Pirelli Cinturato P7 tyres need to go!!!

dArK5HaD0w
08-04-2019, 02:11 PM
the 162TSi Superb comes with a 205/55/16 spare tire.

43935

ope126
09-04-2019, 09:48 AM
the 162TSi Superb comes with a 205/55/16 spare tire.

43935

Thanks for sharing that!
It would seem that the theory of a different "rolling diameter" having an effect on the driveline looks to be incorrect.

As your 205/55R16 spare tyre has a rolling circumference of 78.1inch 205/55R16 Tires (https://tiresize.com/tiresizes/205-55R16.htm), near identical to the 78.2inch in my space saver T125/70R18.

So if ŠKODA is happy to provide different size spares, it mightn't be too crucial for short journeys on the spares in case of emergency...

Also, as a guess the reason why you have a 16" spare tyre and I have an 18" space saver could be due to the larger front brakes in the 206TSI.

Now to find some 245/40R19 tyres...

dArK5HaD0w
10-04-2019, 01:59 PM
Also, as a guess the reason why you have a 16" spare tyre and I have an 18" space saver could be due to the larger front brakes in the 206TSI.

Now to find some 245/40R19 tyres...

correct - the 206 has bigger 345mm brakes up front, while the 162 only has 312mm.
hence the bigger spare for the 206.

when my P7s r shot - i'm definately going 245s.
let me know wat u find in that size.

ope126
17-04-2019, 10:27 PM
correct - the 206 has bigger 345mm brakes up front, while the 162 only has 312mm.
hence the bigger spare for the 206.

when my P7s r shot - i'm definately going 245s.
let me know wat u find in that size.

So I just bought a set (x4) of Goodyear Eagle F1 Asymmetric 3 (Made In Germany) 245/40 R19 98Y XL.
Fresh stock, Week 38 2018.

I haven't put them on yet as I am waiting until Mid June before we go on a Road Trip to Canberra and the Alpine Region...

PM if you are interested to know where I got them, as I got an excellent price!!!

ope126
21-06-2019, 09:28 PM
Tires installed today!!!

Goodyear Eagle F1 Asymmetric 3 245/40R19 98Y XL (Made In Germany)

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