Wheel Sizes (quite technical)

[skod_up_north]

Hi,  

 

I'm new here so please be gentle, I did search first but cant find the answer I need...

 

Just taken delivery of a Octavia 1.4TSi SE 6sp Manual  - happy to answer question in it!

 

I'm currently trying to get a set of wheels/tyres for the winter.

 

On my old car (Vauxhall Astra) I used to have a set of 15" steel wheels with winter tyres that I simply swapped over with the 17" alloys each October.  These came as a complete set from  mytyres   I used the mytyres online guide to select them and had confidence it would work as the Astra was also available from vauxhall with 15" steel wheels.  Told all this to my insurer who did not seem to care as the car was available with the 15" steels and  the wheel had not got bigger!  They have worked fine and mytyres seem to be reputable company.

 

 

Now to the Octavia

 

It's got 16" Ilias wheels - with 205/55 R16

 

mytyres will sell me 16" steel wheel packages - e.g. with a wheel:

 

6 x 16  5 x 112.00 x 57.00 ET: 48.00 5 hole whee

 

What do all the numbers mean - my guess below:

 

6 - ???

16 - wheel diamater in inches

112 -  bolts circle diamater in mm???

57 - ????

ET - Einfac Teif ("pressed in distance") i.e. the offset?

48 - the actual value of the offset in mm???

 

Issue here is the Skoda dealer tells me you can't get the car with steel wheels - thus insurer says its a modification - pain of telling them each year etc etc.

 

Mytyres also sell alloy packages there are many types of wheels - e.g. two types are

 

Enzo G 6.5J x 16 OS 45 (cheap)

AEZ Valencia 7.0J x 16 OS 48 (expensive) 

 

Whats the difference - if the actual offset of the Octavia is 48 (can anyone confirm this?) how come a offset with 45 is recomended by mytyres?

 

the looks don't bother me so I would be tempted to go for the cheaper option.   I'm no car person and I have never bought aftermarket alloys in my life, but I clearly want to know what I am doing!  Can anyone help?

 

Ali.

 

PS as others on here have said - you get what you pay for with winter tyres - I had a set of continental ones that lasted twice as long as some of the cheaper brands you have never heard of.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[philhoward]

The 57 is the centre bore of the wheel.  6 is the rim width in inches (inner edge where the bead sits).

 

I see from the brochure that you can get a "Temporary Steel spare wheel" as an option - doesn't say if thats a skinny space saver or a "full size" steel though?  If you (or another owner) has one, then the size and offset might give a clue to what steels you might need?  Is it in the handbook?

 

Spec of the original wheels looks to be 6.5J, ET46 - so a 6J would probably be ET48

Edited 23 September, 2013 by philhoward

[KenONeill]

What tyre size are Mytyres mounting on the 6x16s?

[skod_up_north]

Thanks all - Got to admire the speed of response   My tyres are offering 205/55 R16 (in various speed ratings) on all the 6.0 steel and 6.5J alloy wheels and on the "7.0J.

 

http://www.mytyres.co.uk/cgi-bin/komplettrad.pl?cart_id=83496343.110.30976&Cookie=&CGISESSID=61a3344ea2647c3803493d5f57771474&Change=Rim&language=EN&dsco=110&typ=winter&Zoll=16&RadHerstellerFilter=.&Hersteller=AEZ&Typ=Valencia%20dark&Farbe=Black/polished&BestellNr=AVAP8BP48#mainnav

 

(if this does not work go to http://www.mytyres.co.uk/cgi-bin/rshop.pl?dsco=110&cart_id=83496343.110.30976&s_p=Complete_wheels

and select Skoda Octavia)  

 

I have the temporary spare wheel - its full size (cost me £100 as option including jack and a piddly little socket set) will go look for markings on the wheel it.  cant see anything  useful in the Owners manual on this and the dealer seems not too knowledgeable either other than telling me you can have 4 temporary spare wheels on it!

 

@philhoward  - how do you know the spec of the original wheels?

 

@KenONeill - thanks  I'm still confused...  As I understand it from your post the differences between the two wheels are the width of the rim 6 and 6.5 inches.  

 

(6.5 - 6.0) = 0.5 inch. 

0.5 * 25.4 = 12.7mm  

 

Looking at the three wheel widths on offer: 

 

Steel 6.0inch  ET = 48

Alloy 6.5inch ET = 45

Alloy 7.0inch ET = 48

 

So both the 6 and 7 inch wheels have the same ET but the 6.5 has 45 - can this be correct it seems strange???

 

bit of a stupid question is the ET / OS set by Skoda i.e. "wheels must have an OS of 48" - or is there some other dimension specified by skoda that has to be met using a wheel of a specified width  and ET/ OS value?

 

PS Anyone know what a "J" is after the diameter?

 

Thanks!

[TeflonTom]

bit of a stupid question is the ET / OS set by Skoda i.e. "wheels must have an OS of 48" - or is there some other dimension specified by skoda that has to be met using a wheel of a specified width and ET/ OS value?

PS Anyone know what a "J" is after the diameter?

Thanks!

the wheel offset/ inset requirement is a product of the actual mechanical design of the car, this takes account of the suspension geometry and angles etc and also allows for clearance space for the brake caliper, changing the offset or width of a wheel can have an adverse affect on the handling....

and the "J" thing on a wheel diameter is in relation to the profile of the tyre bead, ie the shape of the rim edge where the tyre meets it. There's all sort of types, j, jj, k, jk, b, d etc etc, there are also about 10 different hump profiles on wheels too which relates to the contour of the inner face of the wheel overhang for hub/caliper clearance but you can disregard these measurements.

[philhoward]

I just googled - and found a website selling the standard alloys (in CZ) where it told me...

[spacenase]

I just googled - and found a website selling the standard alloys (in CZ) where it told me...

 

Come on, we're all on tenterhooks!

[philhoward]

http://eshop.skoda-auto.com/cz/en/b2c/wheel

 

They show wheel trims for sale, so at least one market gets steel wheels as an option...

[RNPhoto]

If you're feeling brave (or you're good with languages) go to the Danish site http://www.skoda.dk

Only Elegance trim and the RS models gets alloys as standard! I'm not quite sure on the rim dimensions but the tyre is 205/55 R16!

 

 

As for the different measurements, most have been mentioned but just a few clarifications:

Just because my inner kid I wants to show off my math skillz  :strong:  ....

16 - wheel diamater in inches

ehm .. RIM diameter in inches, yes!

 

205/55R16:

205: Width of the tyre in mm

55: Profile, meaning height of the tyre side in percentage of the width.

16: Rim size, or to be precise size of the hole designed for the rim (obviously ... )

 

Total wheel diameter calculation:

Width*profile*2 + Rim size = 205*0.55*2 + 16*25.4 = 631,9mm.

[skod_up_north]

If you're feeling brave (or you're good with languages) go to the Danish site http://www.skoda.dk

Only Elegance trim and the RS models gets alloys as standard! I'm not quite sure on the rim dimensions but the tyre is 205/55 R16!

 

Tak RNphoto jeg bor i Norge for et år     I can just about read the Danish (yes I know its not exactly the same and you are very different countries etc etc).

 

Seems the steels are  called  16inch "Tekton" wheels  - but  googling does not show them elsewhere, a further look at the UK Octavia manual under "snow chains" says can only be fitted to  

 

6J x 16b Depth = 48 mm Tyre = 205/55 R16

I assume  "depth" is ET?

 

As its listed in the manual it means the wheel is available for the car, I am guessing this is the spec of a "Tekton"?

[The Plumber]

The correct size for the Octy III are;

 

6.5Jx16 ET46 for use with 205/55 R16 tyres (snow chains not permitted)

 

Part number for 6.5Jx16 ET46 steel rim is 5Q0601027A  or 5Q0601027F

 

 

 

6Jx16 ET48 for use with 205/55 R16 tyres and snow chains

 

Part number for 6Jx16 ET48 steel rim is 5Q0601027H

 

 

 

TP

[RNPhoto]

Tekton is the plastic cap to make the steel rim look "alloyish" 

I saw another design for a cap, I think it was in the e-store, but not sure.

[bouff34]

Like the OP I'm confused!

 

Mytyres suggests Enzo G 6.50Jx16 OS45 with 205/55R16 91H  (this is to run winter tyres on - I won't need the use of snowchains).

 

 

Will these wheels fit? Posts above seem to suggest the offset has to be 48??? And the original spec wheels on my Elegance, Ilias, would have been OS46 (although I'm upgrading to the Golus alloys)?

 

Confused!!

 

Bouff34

Edited 24 September, 2013 by bouff34

[philhoward]

I very much doubt 2 or 3mm difference in offset will make a big enough difference to worry in the great scheme of things on a standard car.  There should still be more than enough clearance given the wider rims offered on the vRS..

[bouff34]

I very much doubt 2 or 3mm difference in offset will make a big enough difference to worry in the great scheme of things on a standard car.  There should still be more than enough clearance given the wider rims offered on the vRS..

  OK. Thanks.

[RNPhoto]

Sorry if this is an abundant post at this point , but
I'll give it a shot at explaining ET (or offset) a little more thoroughly:

The offset is measured in mm from the center of the wheel to the actual mounting surface, ie. the surface where alloy is mounted to the brake.
If the offset is a little too small you'll have the upper outside corner of the tyre scraping against the inside of your fender at high loads. If the offset is extremely small, the tyre will stick out from the side of the body (which is illegal in most, if not all countries).

If the offset is a little too big you may have the wheel scraping against the wheel well when turning or scraping against brake/ suspension components. If the offset is extremely big you may even have troubles mounting the wheel because the rubber is touching the spring.

However, when you mount a narrower tyre you'll have more clearance on both sides of the wheel, and should in theory be able to choose a smaller offset.
In theory if a 225mm wide tyre requires an offset of 48 a 205mm tyre should be able to go to:
Extra clearance on each side at same offset: (225-205)/2 = 10mm
New smallest offset: 48-10 = 38mm / ET38
... in theory! Don't quote me on this, but I believe the type approval (err .. is that the right expression?) for a car sets some limits to the actual offset.
And as stated above, testing the limits may have an effect on handling! I would guess it has an effect on component durability as well, since you could end up with the forces going in odd directions (although I have absolutely no scientific data on this).
 
Link stolen from an Audi forum I found when googling:
http://www.rimsntires.com/specs.jsp
It's a nifty little tool where you can choose the different dimensions and see what effect it has on clearances and even the speedometer!   There are also some nice drawings to show what the different dimensions mean. I found them slightly confusing to read even though I had a fairly good grip of it to begin with, so if you're still confused you may have to look back and forth at the drawings and the descriptions above a couple of times.

 

HTH.

[skod_up_north]

Thanks RNPhoto - I also did some research and spent a happy lunch hour drawing sketches and doing arithmetic...  I can can also offer the two links below:

 

http://www.driverstechnology.co.uk/wheel-offset.htm
http://www.raceandroad.com/technical-help/alloy-wheel-offset.html

 

 

In my case I do own a set of snowchains that are occasionally used (live at the bottom of a big steep hill)  so I shall get the MyTyres steel ones 

 6 x 16  5 x 112.00 x 57.00 ET: 48.00 5 hole wheel  with 205/55 R16 91H Tyres.

 

This as a standard size (one of three) for snow chains and is also listed in the Owners handbook , pp 213 of 

http://ws.skoda-auto.com/OwnersManualService/Data/en/Octavia_5E/03-2013/Manual/Octavia/A7_Octavia_OwnersManual.pdf

(on the paper manual the same info is on pp226)

 

So I have a high confidence the wheel size it's "approved" for the use on the vehicle (and I don't think I need to trouble my insurer)

 

It's also listed by "the plumber" above - although I note he also lists  

 

6.5Jx16 ET46 for use with 205/55 R16 tyres

 

Which I don't see in the owners manual, not trying to dispute just curious as to the source.

 

the Mytyres results for Alloys are not logical 

 

 

Steel 6.0J ET 48

Enzo G 6.5J ET 45 (width increases, offset decreases c.g. 6.0J)

Enzo B 7.0J ET 48 (width increase, offset same c.f .6.0J)

 

 

What we don't have on here yet is what alloys are "approved" for the use on the vehicle as they are not listed in the owners guide,  I can see three ways to get it:

 

1 - someone @  Skoda  posts it!

2 - Ask a dealer who is actually helpful (sorry I cant help)

3 - Remove existing skoda Alloy wheel and see what the marking is on the rear

 

I am game for (3) but not before the weekend.  

 

as philhoward says 2-3 mm  may not make much practical difference, particularly if you have a VRS with wider arches anyway (I'm no boy racer so cant comment), but too your insurer - should you have the misfortune to have an accident - it could be all the difference in the world 

[The Plumber]

The following link lists of all rim and matching tyre sizes as approved by Skoda, published by Skoda Germany; a little bit more clued up than our Skoda UK

 

Oh they update it usually a couple of times a year.

 

 

http://www.skoda.de/download.php?id=769

 

 

To find the original link go to this page and look for the PDF on the right of the page.

 

 

http://www.skoda.de/index.php?e=348-10-23

 

 

TP

[skod_up_north]

Many thanks TP, this is quite useful to many reading I think...  

 

The V5 turned up in the post today so I have the type approval number, this then gives the page in the table and the appropriate wheels available - for anyone reading - a few translations...

 

motorkenbuchstabe - motor code (this is on the V5 green section P.5)

typschusselnummer - typical key code (no idea what this refers to)

ReifenGrosse - Tyre Size

Felgengrosse - Rim Size

ET - offset 

Schneeketten - compatible with snow chains, based on 15mm chain  (yes or no)

 

 

More interesting is the first paragraph of the web page which says something like:

 

"Since 1 Oct 2005 the registration documents show only 1 tyre size before this all sizes approved for the vehicle were listed.  We have produced this list so owners / keepers can select other tyre sizes that are type approved"

 

So it appears the German auto driver has had this information for many years on the "V5" and when it stopped being published Skoda decided to keep publishing it.

 

Vorsprung durch technik...  

Edited 25 September, 2013 by skod_up_north

[The Plumber]

Believe the typschusselnummer is the trim level.

 

 

TP

[SorinM]

the official R15" rims for O3 is  6,0J x 15"" ET43. This size rims are more expensive than ET47 rims. The offset is only 4 mm. Do you think I'll have problems using the ET47 rims? Has anybody used these kind?

 

Thanks!

[multiskoda]

The following link lists of all rim and matching tyre sizes as approved by Skoda, published by Skoda Germany; a little bit more clued up than our Skoda UK

Oh they update it usually a couple of times a year.

http://www.skoda.de/download.php?id=769

To find the original link go to this page and look for the PDF on the right of the page.

http://www.skoda.de/index.php?e=348-10-23

TP

Exactly the info I've been looking for, except the links no longer work :(

Anyone know where the latest version can be found?

[The Plumber]

Latest links;

 

http://www.skoda-auto.de/service/serviceleistungen/serienbereifung

 

http://www.skoda-auto.de/SiteCollectionDocuments/Serienreifen_Skoda_2014_07_1.pdf

 

 

Regards,

 

TP

[multiskoda]

Thanks to The Plumber

[Geek42]

Believe the typschusselnummer is the trim level.

 

 

TP

 

I'm not sure this is right. I looked this up when I got my car about 4 months ago and memory's hazy, but I think I found a reference on the web that described Typschusselnummer as a combination of body style and some other quite major 'features' such as having 4x4, or maybe the gearbox type or something. If I can find it again I'll post it.

 

Big thanks to the Plumber though, as I think it may have been your link in another thread that I followed 4 months ago. Excellent info!