Tyre sizes for 9" 20s?
 

I'm considering putting my (spare...) set of 20 rims - which are 9" rather than the "proper" 8.5" ones - on my S8 as winter wheels this year.

Am I right in thinking that these 9" rims would take the same size tyres as the 8.5" ones, which this page suggests, I think?:

http://www.audipages.com/upgrades/tiresizeoptions.html

0.5" yeah same size should be fine

Yeah 255/35-20 will be fine on 9s - that's what I'm running

Grand, thanks +++

Additional winter wheels/centre caps question...
 

I have a set of centre caps - suitably darkened to match the winter rims - from a "spare" set I had lying around - but they seem to be a very tight fit, and I'm concerned about them not fitting, or the lugs breaking if forced :(

Is this a sign that they're cheap Chinese ones (quite possibly why they were lying around :ROFL: ), and is there a knack to persuading them to fit snugly?

Yes

In this weather I'd put them on a radiator for a couple of hours to warm them up, then WD40 on the tabs and some percussive maintenance! Make sure the locating lug on the wheel is lined up with the slot on the outer edge of the cap. Hold that in place and then a solid whack on the centre of it should get it to drop in place.

Good luck getting the buggers out again though :rolleyes:

Cheers! Good practical advice, as ever. I'm less worried (for now...) about getting them out again - I might leave that to my friendly KwikFit manager as a springtime challenge for him ;)

Yes and not really. I'm sure I posted somewhere (here ages ago) about how to tell the difference and one way to make them fit better, but there's no "knack", just brute force unless you "customise" them.... :rolleyes:

IIRC the lugs are a different, more rigid, shape and the spring rings are stronger too vs OEM. I think I got some of my cheap Chinese ones to fit by using much weaker rings from a completely different set (non-Audi) of spare/redundant wheel caps.
You might also want to look at the lugs and consider carefully paring some material off to make them more like OEM.

Edit: See this from 2017: http://forum.a8parts.co.uk/showthread.php?t=13223

Details on how to tell OEM from fake here: http://forum.a8parts.co.uk/showpost....0&postcount=64

And looking at other comments the spring ring is usually a major part of the problem and needs about 5mm cutting out of it so it will close further, or a weaker replacement. +++

All done now...
 

Well, maybe I was lucky - or maybe my luck will run out when taking them off in springtime :( - but these dodgy centres went on with little fuss.

They're certainly not as slick or an instant snug fit as the real thing, but no heating, trimming or real forcing was required - although for 2 of the 4 rims I did have to "reposition" one of the set of 6 sprung pins to inside (rather than outside..) the retaining ring. That seemed to make them slot in more easily, but it may also mean that they're slightly more likely to fall off, though they all seem pretty secure.

Time will tell, and it's not like I'll be using Herman as my daily driver/for long trips during the winter, so hopefully they'll be jus' fine :)