Ditching the Run-Flats

[Jgc650i]

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Swapped out the stock 20s on run flats for a set 19s with non-run flat winter tires. Huge improvement in the ride quality and am planning to put non-run flats on the 20" 373M wheels before putting them back on the car in the spring. I know there have been previous posts on this topic, but looking for updated thoughts/recommendations. For those who have gone to non-run flats on the stock 20s, what tires would you recommend?

[J4193]

I got the 20 with gt maxx performance tires and I think my ride sucks should I switch to all season tires? I live in chicago

[BillCB]

Personally, I really like RFs - both 20 inch stock (Dunlop) for summer and 18 inch for winter. The winter ride is better, but the cornering (at speed) certainly isn't.

I've used nothing but run flats for the last 8 years and have no complaints. And I'm not sure that non RFs on 20 inch wheels will give any better ride - you're still going to have a very low profile tire.

As for Chicago, whose climate isn't very different from Toronto where I lived for 30 years, I wouldn't use all season tires. They're still like hockey pucks at much less than 40F, so unless you only drive very conservatively on cold days and there's no snow, I'd put on winter tires. (Note - they're not called "snow" tires any more because their best quality is adhesion at low temperatures. That extra foot or two of stopping power in traffic might be a life saver or at least a visit-to-the body-shop saver.)

Cheers,
Bill

[neversummer78]

Originally Posted by BillCB

Personally, I really like RFs - both 20 inch stock (Dunlop) for summer and 18 inch for winter. The winter ride is better, but the cornering (at speed) certainly isn't.

I've used nothing but run flats for the last 8 years and have no complaints. And I'm not sure that non RFs on 20 inch wheels will give any better ride - you're still going to have a very low profile tire.

As for Chicago, whose climate isn't very different from Toronto where I lived for 30 years, I wouldn't use all season tires. They're still like hockey pucks at much less than 40F, so unless you only drive very conservatively on cold days and there's no snow, I'd put on winter tires. (Note - they're not called "snow" tires any more because their best quality is adhesion at low temperatures. That extra foot or two of stopping power in traffic might be a life saver or at least a visit-to-the body-shop saver.)

Cheers,
Bill

I think RF on BMW is quite good but not on Mini. I had 2010 MCS convertible with sport package with 17" RF and the ride was super poor. I made the matter worse by lowering it, but then I switched to Kumho ECSTA and it was night and day. However, RF on 3, 5, and 6 series, they are not so bad.

By the way, does anyone happen to know the tread life expectancy on the stock Dunlop 20". I just detailed my 6er this past weekend and they don't look like they have many miles left on them. I currently have 7200 miles.

[BillCB]

I had 21,000 kms, about 13,000 miles on my 20 inch RFs before I put on my winter tires. I'd guess the tread had about that much again on them - probably good for a total of 25,000 miles.

But that's just a guess until next summer!

However, nearly all my driving is highway with very little stop & go, so YMMV!

[neversummer78]

Originally Posted by BillCB

I had 21,000 kms, about 13,000 miles on my 20 inch RFs before I put on my winter tires. I'd guess the tread had about that much again on them - probably good for a total of 25,000 miles.

But that's just a guess until next summer!

However, nearly all my driving is highway with very little stop & go, so YMMV!

Thanks for the info BillCB

[Bönz]

Originally Posted by BillCB

I had 21,000 kms, about 13,000 miles on my 20 inch RFs before I put on my winter tires. I'd guess the tread had about that much again on them - probably good for a total of 25,000 miles.

But that's just a guess until next summer!

However, nearly all my driving is highway with very little stop & go, so YMMV!

I changed over to my winter set up a few weeks ago and noticed the rear 20s were down to the wear bars. Hard to know exactly how many miles since I don't track when I switch back and forth, but I would estimate they have between 11k and 12k miles. They are toast. No way they would last 25k, but I do very little hwy driving.

[BillCB]

FWIW, I had a 2005 645C1 for 8 years. When I gave it to my son it had about 130,000 kms on it. In that time it had gone through one set of summer RFs and one set of winter RFs.

At the time of transfer the second set of summer tires was mostly used, likewise the second set of winter tires, though they will last this season. So one can deduce that the car went through a bit less than 4 sets in sets of tires in 130,000 kms.

130,000 kms divided by 4 = 32,500 kms or roughly 20,000 miles per set.

This a very rough and ready estimate. Probably the summer tires had more on them than the winter, though like Bonz, I don't keep records of when I change them over in spring and fall.

However, these figures are quite consistent with my 2014 GC as I mentioned above.

Bill

[neversummer78]

Thanks all, I think it is good information to have for what kind of miles I can squeeze out of OEM set, so I can start collecting coupons from those tires stores and get them ready for my next set.