I just picked up a tirer truer and was wondering what would the recommendable size be to cut down my tires(front and rear)? Just like a starting point or average? and about have far down can tires be used? For trc fronts do you need four flanged bearings or only 2? I am seriously thinking about going trc becasue my jaco rims are just carcking so badly(i guess if i didnt hit the wall so hard i wouldnt be cracking them though )