Tyre fitment options for 17x8.5" Turbines/Throwing Stars on e34

[genphreak]

Hi all,

Last time I bought new tyres for M5 rims, I got 'standard' 235/45x17 Michelin Pilots. Great tyres but my pet hate is the rims stick out enough to be easily damaged if I lend the car to mumma to go shopping. On a 17x8 ET20 rim, can I fit a slightly wider tyre to avoid the problem?

Stock tyres are 235/45x17. Theoretically these have a 106mm wall, Est. diameter 643.3mm

The options seem to be:


10mm wider; lower 245/40x17 98mm wall, Est. diameter -15.5mm; 627.8mm
10mm wider; 245/45x17 higher 110.25mm wall, Est. diameter +9.1mm; 652.3mm
The additional sidewall (for shock absorption) and width (for rim protection) would be beneficial for the car. I think it will handle the extra width just fine, but will the additional 9mm diameter cause problems apart from a low speedo reading?

20mm wider; 255/40x17 higher 102mm wall, Est. diameter -7.5mm; 635.8mm
Will they rub? Where?


Not a good set of options really, maybe I have to buy stock and just never let anyone else park it...

Any experience/comments are welcome. Hopefully someone will have some good news for me ;-)

[Tiger]

Or you can just buy the tire with rim protection built in... a lot of sport tires has that feature built in. It all depends on whaat brand you buy.

[genphreak]

Thanks for the suggestion, Tiger!

I bought Kumho Ecsta SPTs (http://www.kumho.com.au/ecsta-spt-ku31-product-reviews/) for the 16s on the daily driver a while back. They stick well in the dry but have no rim guard to speak of. But I doubt rim guards work too well when the tyres are not wide enough for the rim. (I always considered 245 the right tyre for an 8" rim)

However 225 is very good on the 16x7.5s, so maybe I should just get 235s on the 17x8.5s). Will check Michelin's range as well as a few others.

Definitely will get a set with this feature no matter what size.

[Tiger]

On my MB, I had a 16x8 with 225/50R16... it works just fine. with the curb guard... it only protects you on minor curb rash as in backing up slowly... a sharp turn into the curb... nothing can protect you.

On my BMW, I had 235-45R17 on I think 17x8" also... BMW wheels... and that one really did protect my rim... high local speed (about 35MPH) curb rash... aftermath was like a normal curb rash... This was Nitto NT555... rough riding tire, otherwise quiet on highway but noisy on local road when tire wear down. Still the same design after 13+ years on market... so it is an old old tech now... at the least for tread design... maybe tire composition has changed.

[genphreak]

On my MB, I had a 16x8 with 225/50R16... it works just fine. with the curb guard... it only protects you on minor curb rash as in backing up slowly... a sharp turn into the curb... nothing can protect you.

On my BMW, I had 235-45R17 on I think 17x8" also... BMW wheels... and that one really did protect my rim... high local speed (about 35MPH) curb rash... aftermath was like a normal curb rash... This was Nitto NT555... rough riding tire, otherwise quiet on highway but noisy on local road when tire wear down. Still the same design after 13+ years on market... so it is an old old tech now... at the least for tread design... maybe tire composition has changed.

The Yokohama Advan tyres are probably the best bet, quite cheap at $170 and are very good. they have a pretty solid looking shoulder in comparison to most- so look like they will protect the rim well. Couldn't find any Nittos here in Oz.

made the decision today, and went the safe conservative route to maintain OE feel. Chose 235/45x17 Michelin Pilot Sport 3s. Not directional, which is most practical on m-system wheels which are also have a directional design; combining both makes it harder to swap tyres around once they begin wearing.

They cost AUD$220 per tyre fitted at a decent shop. Probably cheaper in some other countries.

Needless to say they drive superbly. Low noise and super sticky in all conditions. Very happy, though improbably should have bought the Yokohamas for the sake of the rims. The new Michelins do have a protection lump, but it is quite insubstantial- interestingly the Pilot Preceda's (like Sport 2s, but made for hotter and wetter Asian conditions) which I have on the other car have a far bigger protection shoulder than the new tyres. I'm really going to have to be hyper careful with these ones :-(

If I'd seen them on the rim before buying them, I would have got the Yokohamas for sure.

That said, I'm sure enjoying the drive!

[Tiger]

That's good choice. A little protection go a long way... we are not in a habit of curbing our wheels on purpose!