Yes there is. You'd want to test two things which are core to what we are discussing here: 1) Slip-out angle. It is measured as a simple angle with a given downforce. 2) Co-efficient of friction in a straight line. (It's been called grip and traction here' date=' all the same thing measured the same way. There is no unit for the coefficient of friction, it is merely a coefficient. But that's not English in your book. Forget about doing a riding test, that's just too messy. You'll have to do the tests statically. For the co-efficient of friction, I suggest you cut a piece out of your mate's directional tyre. A length of about 100mm should do the trick. Flatten it and nail it to a wooden board. Load the wooden board with a couple of bricks and attach a string to each end of the board. Now pull the board on a uniform surface with one of those fishing scales and get a reading. Pull it from the other side and get another reading. Do that several times, throw away the extreme results at either end and average the bunched results. See if it differs significantly from left to right. For the slip-out angle it'll be a bit more difficult. You'll have to get two tyres where the surface area and depth of the two sets of knobblies differ in looks but are exactly the same otherwise. Then you'll have to apply a known force to each wheel and slowly tip it (on your preferred surface) until it slips out. Measure that angle and compare the two after you've taken away the "noise" in the experiment as described above. This would be a real world test. I've never seen any tyre manufacuter perform and publish the results of this test. [/quote'] On a small point of correction. Your test does not simulate (check I have fixed the spelling) real world conditions. TYre are not flattened onto a box in real world conditions (they are round. Pies are not square). So the contact surface will be considerably different when the tyre is Flattened out. Secondly, tyre are normally rolled over obstacles and srufaces and not dragged (unless you are braking hard, but then you will be over the handle bars) SO to simulate treall conditions you should use the complete wheel connected to a improvised cart which is then rolled over various surfaces at diferent speeds and angles. Data is then collected from how far the wheel rolls or how much dirt is displaced ext. I know you ae a stickler for correctness, and this is why I propose that your expeiment won't measure what you want it to ( relevancy)