So I picked up this pile of a bike for a couple hundred bucks and I'm starting to get through rebuilding the engine. Looking for some help on anything I should look out for on the 02 model specifically. Goal is to do full engine rebuild and have a fun/reliable backup to my 06 crf450r. I only ride trails and dunes, no track. Some quick questions, I've heard many people are scared of the auto cam tensioner (especially the early crf tensioners). I do NOT want a manual one, are there any options for a better auto tensioner? (as in a newer crf tensioner that would fit) Piston options, would prefer oem. Can I fit/should I fit a piston from a newer crf? What years work and with it fit properly with an oem 02 head with stainless kibble white valves? Planning on having the head done by fast heads with stainless valves and already have a brand new oem crank and a clean oem cylinder. Also have an 03 or 04 airbox already and a full yoshi exhaust. Any other hints or issues that I should fix that are specific to an 02 I'd appreciate! I'm plenty mechanically inclined just lacking in knowledge of this particular bike.