Hey guys, i'm looking at getting a used 5-speed 450 for trails, free riding, and off-road racing. I've been looking at the yz450 and the crf450. I've spent a bit of time in the crf forum trying to get info on that bike. seems like the two main issues are valve problems (may or may not be a problem for me because i lug a gear high, but very $$$) and overheating issues on slow trails (could be a big pain for me!). How is the YZ in these two issues? From what I understand the only issue i might have with an 06 YZ would be the leak jet. how much are the zip ty units that are so popular? Is the 2003 yz450 a 5-speed? just curious, i thought they were all 4-speed until 06 but someone told me the 03 was a 5-speed.