Convert to a woods bike or ???

I should preface this post by saying I've checked many previous posts to learn about converting a YZ450F into a trail bike. I do most of my riding in the Cascade Mountains in Washington. Lots of elevation gain and some pretty steep trails... My XR400 is perfect out here. My unique situation is that I took in a 2004 YZ450F as part of a business deal. The bike is flawless with less than 10hrs on it. It was just sitting in storage all these years... I could sink $$ into it by changing the sprockets, changing the exhaust, putting weight on the flywheel, changing the gears... The list could grow. I'd rather be sitting here with a WR in the same condition, but that will probably be impossible to find. Is it worth it to sell or can I get a good bike through trade? Any suggestions?

why not ride it and see if you like it first?

I ride a yz426 as a trail bike and love it. I am going to gear it down and add a auto clutch.

I ride trails but prefer track, I have the 2003, so it's a little meaner than the 2004 powerwise, that said, add the Yamaha Off Road Flywheel and you will have a tractor that just pulls like you wouldn't believe. Very strong down low and it doesn't stall easy, It is absouloutly awesome from the bottom up. I also did a revalve thourgh factory connection and a Scott's dampner. The bike is phenomanal. I love it, and I love it on the single track and trees that I have had it in. My sporcket is stock, which with as much torque as you have, works great. Ample power, but the heavier flywheel makes it manageable. The suspension was a great investment. I can't begin to tell you how much it helps to have it done to your riding type and ability. Also, I will never own another bike without having this scotts on it. It's like cheating. After my mods, the bike has superb manners and fantastic tractable power. I would go flywheel, re-valve, and scotts, in that order. You'll go $150, $400, $400, for those modifications, and have a bike that is tough to give up. Make sure you get your jetting dialed too, and then have fun. An congradulations on getting a fantastic bike for a killer deal.

Last weekend I finally got out and cleaned the carb, changed the fluids, etc. Started it and man did it rev! This was my first time sitting on anything other than my XR and I was blown away. It really was scary fast. That said, it was easy to stall, 1st gear felt too tall and 4th gear felt too low. It's really surprising to imagine it could ever have much grunt down low, but I guess if you can channel all that power, anything is possible. Something else that was on my mind was the jetting. I know these bikes can be finicky, and in an average ride I'll be up and down between 2,000ft-6,000ft above sea level. I had to outfit my XR with a Mikuni pumper carb just to get a wider range of power. Can I get good performance out of the YZ under these conditions? Also thinking about lights and noisy pipe... I just got to thinking, man I bet this bike would tear up the dunes in Florence, OR. I was down there on my XR a couple times and I could have used the extra power. Decisions, decisions...

It'll never chug like a xr400 IMO, but a heavy flywheel and lower gearing and a little time on it you'll like it. A G2 slow throttle is also a good option. The 4spd box might be a hindrance though. Another might be fuel range.

...and in an average ride I'll be up and down between 2,000ft-6,000ft above sea level. I had to outfit my XR with a Mikuni pumper carb just to get a wider range of power....

I've ridden my WR from sea level to 6000 ft without changing the jets. Believe it or not the big bores with the keihien FCR aren't as sensitive to jetting. Then again I'm jetted for about 2500-3000 ft so the engine's "lean-ness" at sea level and "rich-ness" at altitude is probably not as bad as it would be if I were jetted for one extreme or the other.

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