Effect of scrub radius

[Roger the knife]

I have been involved in a discussion on the supposed benefits of scrub radius, and I'm interested to get some outside input.

I have always been of the opinion that it is a relatively minor factor in front geometry. All the books and info I can find, say it should be as small as possible, and always negative, except for a FWD car, so I am surprised to be caught in a discussion where someone tells me it is the dominant factor in generating tyre temperature. I can't see it this way myself, but I could be wrong.

I would enjoy the benefit of some outside expert comment

thanks

[Jersey Tom]

I'd say it has crap all effect on generating tire temp.

[DaveKillens]

someone tells me it is the dominant factor in generating tyre temperature

I'm afraid this statement is incorrect.

The scrub radius is the distance in front view between the Steering Axis and the center of the contact patch where both would theoretically touch the road.

So unless the driver is going around ten klicks and sawing ferociously on the wheel, scrub radius would not be a factor in generating tire heat. And even then, it would only affect the front tires.
Scrubbing in tires is a totally different thing, it's an action. I suspect that scrub radius and scrubbing are being confused with each other.
Scrub radius is more about alignment and steering sensitivity, especially under braking.

[RideRate]

He may be confusing scrub and "scrub radius". Scrub is known to put a little heat into the tires, but scrub radius isn't. If you think about how much tire scrubbing actually occurs due to scrub radius you'll realize there's no way it can be a dominate player in tire heating.