This has pretty much happened since I've owned my car at 17k miles, it only has 21 now, but it's been a year. When the car is cold, and I'm cruising at low speeds, like 30-40, there's a little bit of a shake. It feels like it's coming from the rear.

Is this likely to be a tire balancing issue, or is it something that the S2000 suffers from? Anyone else have this?

 

does it happen all the time when the car is cold, or just after it has set for a couple of weeks?


It is possible that your tire cord is creeping and creating flat spots. As the tires warm up the phenom goes away.

 

damn i think this happens to me also! im thinking its just tire balancing...because after driving for about a minute it goes away...hrmmmm bump for an answer lol

 

A lot of various tires will do this when cold. It feels like a balancing issue, but you keep driving and then it goes away eventually. The tires are heating up - normal.

 

Some tires flat spot (on the bottom of course) due to sitting for several hours. This is quite normal and may be more evident when cold weather hits. They quickly round up when driving. The S2000 stiff suspension makes this effect more noticable.
I can't say my Bridgestone's have suffered with this problem but I usually wait until the engine warms up before I stomp on it.
Plus it could be aggravated by a tire pressure issue. I check my pressure often especially when cold weather hits. And I always err on the high side. Traction, especially in snow is worse with low tire pressure.

 

I set my tire pressure to 35psi all around. You are NOT going to get flat spots on tires unless you let the car sit for quite a long long time.

If the vibration goes away, then it can't be a tire balancing issue. Because if it was a balancing issue, it would still continue to vibrate the whole time.