Was working on it on an asphalt paved road out in the country this evening on the way home from work. I found that between 2900 and 3200 rpms the tires bark, they dont really spin but I get one hellacious bark. 2800 and they hooked good. Then it may be higher if I heat em up a bit but I just dont know this is fairly new to me and I havent seen any other posts. So.........