Yesterday, I got rid of my stock Eagle RSA run-flats, and got a set of Yokohama s-drives. For some reason, the rear of the car seems looser than before with the run flats? On a long sweeping curve, I used to be able to pull the wheel and hug the road even more, now it feels like the back of the Mini wants to lift up?

I have a 19mm sway bar on the stiffest setting. Can the change increase the performance of the sway bar? Or did I just get used to the hard ride of the run flats? Has anyone else noticed a different feel after swapping out the run flats? Could my tire ressure have something to do with it? I have 38psi all around.

???

 

You didn't say what size tires you have. To me it seems like your pressures are high. Drop them down a bit & see if it behaves better for you.

 

204/45/17

 

I'd also agree to drop the pressure down to about 36lbs. Secondly, although you probably want to notice an instant improvement, tires take about 300 miles to wear in. They'll be more slippery until the curing compound from the molding process wears off.

 

You need to get some miles on those tires before they achieve full performance. New tires won't grip nor heat cycle properly until the surface layer has worn off. Give it 300 miles and then see how they are.

 

Try 36psi in front, and 34psi in the rear. That should change the slip angles enough to counter what you felt.

 

You just got punked!I just went thru the exact same issue!I bought the S Drives,had them for 3 days and demanded that Discount Tire promptly remove them from my wheels! It's the tire,not your car!I put the Dunlop Star Specs on,and voila the go cart handling returns.I dont know how anyone would be happy with the S Drives.Anyone remotely aggressive in driving style and having a pulse would find these Yoko's most crap!

 

This is normal when going from runflat to regular tires. It sounds like you are describing the amount of sidewall flex. Your rear swaybar is probably a little on the aggressive side in my opinion. To get runflats to rotate the car, a swaybar seems to help (at least people say it does). The softer tires provide a way different feel which I admit was scary at first, but got used to it. It will take some time to adjust. I have yoko parada spec II's, my second set, and like the tire except for its greasy tendencies under extreme track conditions. The S-drives I considered, but didn't know if they would be harsh or not because the load rating on tire rack is XL, or more suited for something the weight of an A4, so I bought parada II's again.

 

I agree with the general opinion, give the tires some miles to wear off the surface layer and reduce the rear pressure.

Anyway, I would have gone with the Bridgestone RE050A...

 

personally i go with goodyear eagle f1's
excelent grip in dry conditions
doesnt hydroplane- works about just as well in wet as in dry ( ive only had it very minorly slip for like .02 seconds when starting on a hill when it was raining)
the sidewalls are a carbon-fibre blend, and are stiff
the only difference i noticed when switching from my pirelli run-flats to the goodyears was the handeling was more nimble cause of the loss of ~50 lbs of weight.
my back end is just as solid as ever though

 

Agreed. S-Drives are soft poseur tires. The Direzza Z1s are the real shizz.

 

If we are touting tires...

Get a set of Nokian V's. Greatest tires I've ever had.

 

Would the load index be the cause of this? The stock goodyear RSA's had a load index of 84=1102lbs, and the s drives have a load index of 88=1235lbs. Load index was not something I even paid attention to when looking at tires?

 

I don't think a 130 lbs difference in load index is going to effect much.

I await a tire expert's opinion with great anticipation.

 

Not an expert either. I agree the above poster.

 

I just ordered some Bridgestone Potenza RE960AS non-runflats for my JCW. That's taking me from a load rating of 82 (1102 lbs) with the Dunlop OEM runflats to 91 (1356 lbs) with the Potenzas.

 

I have an 04 mcS and I absolutely hated my runflats. Harsh riding (& with the sport suspension...) noisy. Changed to Yokohama Parada 205/45 x 17. Softer ride than with the runflats, seem to stick like glue. A little noisy, but I'm well into my second set...

I carry a little porsche compressor in the boot with a tire-plug kit just in case.