I see a lot of posts from people who report their new tires feel squirmy. The following is a good explanation of why, copied from the Tire Rack web site.

Tires are comprised of many layers of rubber, steel and fabric. Due to these different components, your new tires require a break-in period to ensure that they deliver their normal ride quality and maximum performance. As tires are cured, a release lubricant is applied to prevent them from sticking in their mold. Some of the lubricant stays on the surface of your tires, reducing traction until it is worn away. Five hundred miles of easy acceleration, cornering and braking will allow the mold release lubricant to wear off, allowing the other tire components to begin working together. It is also important to note that your old tires probably had very little tread depth remaining when you felt it was time to replace them. As any autocrosser or racer who has tread rubber shaved off of his tires will tell you, low tread depth tires respond quicker."Don't be surprised if your new tires are a little slower to respond (even if you use the exact same tire as before). Their new, full depth brings with it a little more tread squirm until they wear down.

I don't buy that BS at all.

I had a set of Firestones Duellers at one point in the 90s that were beyond squirmy... Fortunately, they had the 30 day free replacement guarantee if I didnt like them.

I tried them for 2 weeks, then ditched them for a Bridgestone. Didn't feel squirmy at all.

There's a lot more to it than just mold release. Sidewall construction design being the biggest part of it.

Believe it or don't, makes no difference to me. But the FACT is that a deep tread will squirm more than a shallow tread will.

Believe it or don't, makes no difference to me. But the FACT is that a deep tread will squirm more than a shallow tread will.

I agree with that statement. Just not the BS that tire rack is spewing about mold release.

I believe it. My Hankooks were "squirmy" at high speeds for awhile. I think the tread compounds are very hard, and you need to wear it down. After going down dirt roads and stuff, these tires are very stable and awesome.

So, its not BS, although some tires can just be squirrelly period due to defects, but thats not what we're talking about here...

do muddin tires take longer to break n or reguler street tire's

All terrains take longer since the compound is harder, but I would think mud tires shouldn't take long because they are softer. JMO though...