I'm in need for tires for my 98 M Roadster and without doing any suspension mods (yet!), I am trying to reduce the "twitchy" feel the car has on the highway. I also want something that is good in the rain (just in case!) I currently have S03's (225 F and 255 R) and the car is not very confidence inspiring on the highway. My car has 50,000 and the shocks seem to be OK. I am thinking of getting the Kumho MX (going with 235 F and 255 R) but I'm not sure if that is the best choice. I want to have good handling but right now, I'm primarly using it is a weekend "fun" car. By they way, I just changed my rotors to Zimmerman cross drilled (Looks GREAT) and AXXIS Ultimate pads and my breaking feels soooooo much more progressive then stock.

what is your air pressure on the tires? that may solve your twitchy handling.

what is your air pressure on the tires? that may solve your twitchy handling.

I am running 35 lbs all around. Too high?

shouldn't be - how's your suspension and alignment?

I'm in need for tires for my 98 M Roadster and without doing any suspension mods (yet!), I am trying to reduce the "twitchy" feel the car has on the highway. I also want something that is good in the rain (just in case!) I currently have S03's (225 F and 255 R) and the car is not very confidence inspiring on the highway. My car has 50,000 and the shocks seem to be OK. I am thinking of getting the Kumho MX (going with 235 F and 255 R) but I'm not sure if that is the best choice. I want to have good handling but right now, I'm primarly using it is a weekend "fun" car. By they way, I just changed my rotors to Zimmerman cross drilled (Looks GREAT) and AXXIS Ultimate pads and my breaking feels soooooo much more progressive then stock.\


Without knowing exactly where front or rear the car is feeling twitchy, try using this chart to do some adjustments (@ least to air pressure):
Driveability Adjustment Grid: use the suspension tuning Link (http://www.lumenique.com/Cars/cargeneral/driving%20p1.htm).

Worse case scenario is maybe tires are just shot ;)

shouldn't be - how's your suspension and alignment?

The suspension is stock, but seems fine. Shocks seem okay. Alignment seems okay as well. Even wear on tires and it does not pull on the highway.

The only other thing it might be is an out of round tire. The car sat for a while before I bought it and maybe there is a flat spot on the tire. No amount of balancing would fix that (you can balance an egg if you wanted to) so I'm hoping a new set of tires will help things (I need them anyway, which is why I started this thread).

Well, if you want tires for highway driving specifically, I wouldn't recommend getting a ultra high performance tire.

I have 2 sets of tires for the car. I have continental ContiExtremeContacts which are all seasons and I have Kumho MX. If you want an eggressive tire the Kumho MX is great (but not in the rain!). If I want a highway tire that will have good wet traction, there is no question I put the Continentals on. The ExtremeContacts give a beeter highway ride and has less of that twichy feel you are referring to. The sidewalls on the Continentals are softer than the Kumho MX.

For what's worth, I used to have stcok 225/45 front, 245/40 back and just got bigger ones, 245/40 & 275/40 in the back now.

My tires were going pretty bald and I had to get a new set of tires right away before a long drive. I ended up going to NTB and got "fulan"(?) tires. I was very skeptical at first but didn't have many choices then.

As it turns out, highway driving noise seems to be on par with stock tires or even quieter. Handling is similar to stock ones but the car sticks to the ground a lot better. Bad weather driving...stock tires were pretty bad and Fulan ones are not much worse even with thicker width.

FWIW, I'm running 235 f & 255 r S03's @ 38lbs & 35lbs which serves me well, but what really got rid of the twitch, are the I.E. subframe bushings...a must mod @ $90.