Wheel size change and useless Skoda helpdesk

[Brockysuperb]

Just changed back from winter tyres (on 16 inch wheels) to the supplied alloys (18 inch) for the spring and summer. Immediately I've noticed the speedometer become more accurate...judged against my GPS.

 

I remembered that with my Mk 2 Combi under the winter tyres setting on Maxidot, I could change the wheel size plus and minus (up to 15 per cent from memory). So went a-hunting...

 

The only winter tyre setting I could find was to set a speed limit warning. So I checked the manual...it (page 221) says the same.

 

So I rang Skoda customer services...and their genius suggestion is to...'read the manual'. I pointed out that I had done that already, so was put again on hold while the technician was contacted again. They came back and said the technician had also read the manual and 'suspects' there is no longer a size setting on the Mk3.

 

1) Can anyone confirm that the wheel size setting which used to be on the Mk2 Maxidot has now gone. That seems totally daft given the car comes with different size wheels, or in my case swaps wheel size depending on season (the winter wheels having been supplied by Skoda also...)? Is there a way round it to ensure the speedo remains correct (and the mileage is also correct - I now realise I'm showing about 5k mileage now, but have probably only done about 4.5k due to the 16 inch wheels revolving quicker!)

 

2) Has anyone else use Skoda customer services...and been told to 'read the manual'. Then when pressing been told 'the technical expert has also now read the manual'. Is there any 'expert' available at Skoda who actually knows about the technical aspects of these cars beyond the manual...which surely is the whole point? I have still not got beyond 'We suspect it's been deleted from this model', which is not clear cut at all. For what it's worth I 'suspect' it also! What I'd like is a definitive answer from the suppliers, and hopefully an explanation of both why and how to remit the issue.

 

Hrrumphhh. 

[philsmith]

Just because the wheel diameter is different should not mean that the overall diameter is different, it would depend on the profile of the tyres.

There are calculators online where you can put in your wheel and tyre size to get the overall diameter; you should really fit tyres to the 16" rims that will give you more or less the same size as the 18" then there would be no problem with the speedo.

[RickTT]

 

Just because the wheel diameter is different should not mean that the overall diameter is different, it would depend on the profile of the tyres.

 

There are calculators online where you can put in your wheel and tyre size to get the overall diameter; you should really fit tyres to the 16" rims that will give you more or less the same size as the 18" then there would be no problem with the speedo.

 

 

 

^^ This. The rolling radius should match within a % or so.

 

What size 16 inch tyres were you running ?

 

The OEM size is 215/60/16

[LeeBB]

That's odd - the spare supplied in mine is a 205/55R16. When I asked at the Skoda garage they said it is a genuine Skoda part (it is) and that is the correct size for the spare (seems to be according to the manual)....

 

So why the 205 in the spare and 215 for road wheels in 16"?

[GaSelle]

Because it's for a S2. There is no setting to change the wheel diameter. Not in the S2 either.

[RickTT]

That's odd - the spare supplied in mine is a 205/55R16. When I asked at the Skoda garage they said it is a genuine Skoda part (it is) and that is the correct size for the spare (seems to be according to the manual)....

 

So why the 205 in the spare and 215 for road wheels in 16"?

 

Because thats the biggest 16 inch wheel and tyre combo the boot will take -

 

(This was my concern regarding the spare, which i expect is limited to 50mph.) Does your spare have a 50mph max speed limit sticker on it ?

 

See this thread..

 

http://www.briskoda.net/forums/topic/393637-spare-wheel-options-oem-sizes/?hl=%2Bspare+%2Bwheel#entry4574236

Edited 7 April, 2016 by RickTT

[Brockysuperb]

Wanted to measure my tyres the old fashioned way - as philsmith said. He's right. On the 16 inch wheels, the tyre diameter is 25 inches (measured the hard way) so the circumference is 78.5 inches. 

 

On the alloy wheels the circumference of the tyres is 83.25 inches (diameter 26.5 inches).

 

The difference is around eight per cent. Bear in mind both wheels and tyres come from Skoda themselves - one alloy original with the car, the other steel supplied for winter use. 

 

Reference GaSelle; I'm sorry, may have just been the L&K combi or even a UK mod, but you definitely used to be able to adjust for this change in size on the Maxidot under the winter tyres setting.

 

But not it appears on the Mk 3. (Or rather, I can't find it in the manual or on the in-car menu..and Skoda UK technical brains 'suspect' that's the case...).

 

Any ideas anyone? Either how to compensate for different rolling wheel sizes...or about the remarkable ability of Skoda UK to RFM (as I can also do...).  

[RickTT]

Wanted to measure my tyres the old fashioned way - as philsmith said. He's right. On the 16 inch wheels, the tyre diameter is 25 inches (measured the hard way) so the circumference is 78.5 inches. 

 

On the alloy wheels the circumference of the tyres is 83.25 inches (diameter 26.5 inches).

 

The difference is around eight per cent. Bear in mind both wheels and tyres come from Skoda themselves - one alloy original with the car, the other steel supplied for winter use. 

 

Reference GaSelle; I'm sorry, may have just been the L&K combi or even a UK mod, but you definitely used to be able to adjust for this change in size on the Maxidot under the winter tyres setting.

 

But not it appears on the Mk 3. (Or rather, I can't find it in the manual or on the in-car menu..and Skoda UK technical brains 'suspect' that's the case...).

 

Any ideas anyone? Either how to compensate for different rolling wheel sizes...or about the remarkable ability of Skoda UK to RFM (as I can also do...).  

 

 

What size tyres are fitted to your 16 inch wheels ?

 

Below are the correct sizes which should be fitted.

 

215/60 R16 95V on 6 ½”x 16” ET41

215/55 R17 94W on 7”x17” ET40 or 6 ½”x17” ET41

235/45 R18 94W on 8”x18” ET44

235/40 R19 96W on 8”x19” ET44

 

The "full size" spare is a 205/55/16 due to the size of the wheel well in the boot.

(I still need confirmation if this spare is labelled as a MAX speed 50mph due to the difference in rolling radius.  The 18inch saver saver is used due to the brake clearance on the bigger engines. )

 

So. some examples compares using the sizes above to comapre the rolling radius which is as you would expect.

 

OEM 16 inch v 17 inch.

 

 

17 v 18

 

 

18 v 19

 

 

16 v 19

 

 

 

But then.. if you / dealer had fit the winters with the 205/55/16's, you will see the difference in rolling radius to the OEM 16's.

 

 

AND finally..

 

As the wheel well on the BOOT of the car is too small to take the correct rolling radius tire... The Full size spare of 205/55/16 and space saver 125/70/18 are a near match, but again smaller than OEM tyre fitments. 

 

 

 

Thanks

Edited 8 April, 2016 by RickTT

[Kungfugerbil]

The "full size" spare is a 205/55/16 due to the size of the wheel well in the boot.(I still need confirmation if this spare is labelled as a MAX speed 50mph due to the difference in rolling radius.  The 18inch saver saver is used due to the brake clearance on the bigger engines. )

Just checked the spare on mine, and it is a 205/55/16 Michelin on a steel wheel as expected. It *is* marked 50mph only. It can only be due to the difference in rolling radius as you suggested, as it's certainly more than enough wheel/tyre for normal use.

[RickTT]

Thanks for confirming.

The skoda website for the hatch only lists one wheelm ..

The estate list 2.

Before it used to say full size and the other as a space saver.

With one having the yellow sticker and the full size not.

Looks like their documentation was not correct on launch !!!!

So even now.. They are offering 2 options which limit you to 50mph.

Surely the best option is to just offer the one wheel depending on the engine choice for brake clearance.

Edited 8 April, 2016 by RickTT