I changed the front rim on my '05 and moved the brake rotors over to the new rim. After I got the wheel back on the bike I noticed the arrow on the rotors were going the wrong way. Why is there a dedicated left and right rotor? They look symmetrical-Not vented like on a car or something like that that would make a difference. I rode about 50 miles and they seem to brake better now. I cleaned and lubed the brake pad guides and straightened the rotors which may be why they brake better. Just curious if left/ right really makes a difference?