Just bought an 06 yz450f. I can already tell this is quite an upgrade from the old 2001 yz426f that I had. Is there anything that I should look out for on this bike? It seems to have been maintained extremely well and has a lot of aftermarket upgrades such as full exhaust, Rekluse clutch, steering dampener, fork bleeder valves, axle blocks. Also, the head was just rebuilt by a local shop with the paperwork to prove it.