First of all, hi to everyone. I've never been to this forum before, but it looks like the right place to be for a guy who has a couple of questions. If these questions have been asked a billion times, please direct me to the appropriate thread. First a little history: I bought a 2000 YZ426F recently and it is totally stock as far as I know. It's been in storage for a couple of years actually, and before that an older motocross racer/mechanic owned it and he wasn't a hard racer by any measure. I think the bike saw one season. He was apparently very meticulous about maintenance. Needless to say, the bike appears to be in great shape, and rides nicely. Anyhoo, I've ridden it for a couple of days now and immediately have a couple questions. My style of riding is mostly just Sunday-afternoon-with-the-buddies type of stuff. We go hill climbing, rip up the local sand pits, cruise along through fields and do some trail riding. One thing I've noticed is this: There's plenty of power when you crack the throttle wide open in all gears, no hesitation or wavering performance. But as I get close to the top end of each gear, the power seems to waver and won't return until I either shift to the next gear or slow down and then crack the throttle open again. Admittedly, I like to get the most out of each gear on straight runs, and I would have to say that I must be getting close to what I would consider the redline threshold(but I only have my ears and the sound of the engine to tell me that). I know it's not over revving. Is this the so called "rev limiter" cutting in, or could it be something else? The other thing is this: I know this bike was meant to be on a track as a motocross machine, and I knew it would have limitations as far as low speed trail riding was concerned, but I never knew how limited it really was. My friends and I do a mix of hill climbing, sand pit goofing around sessions, and straight open cruising. However, we also ride through some really winding, rutty trails in wooded areas and I have stalled this bike more in the last two days than I've stalled any other bike I've ridden in my entire riding history! You can not putter along switchback trails in first gear without stalling or riding the clutch all the time. At very low speeds I get a "clacking" noise from the chain when it's on the verge of stalling. I've heard of several solutions from friends and other people on this board. Stuff like putting on a one tooth smaller front sprocket, or a 12 oz. weight addition to the flywheel, or even the addition of some kind of clutch modification. What's the most effective modification to allow me to ride slow over bumpy, twisted and cramped backwoods trails without sacrificing too much power/acceleration/speed in other situations What do these mods cost?