First, i ride mostly in woods. I was thinking of getting the 10 or 12 oz. stealthly flywheel replacement and also thinkin of the thunder alley (slip-on) for $250. Also, the gearing, i left the back sprocket the same and went one lower on the front (i think 13). It takes too much top end away. I guess leave the stock front and go to a 50 or 51 in back,huh? Also, would i just be better sticking with the stock pipe in the woods, thunder alley too much hit. Also wonder about heavier flywheel/Thunder alley combo? Anybody tried it yet? I'm 6'7", 235 lbs. Just sold my KX-500, don't miss it a bit. Thought I would never let it go. Any help appreciated.