(EDIT: I dunno what a "tumbs" is... if someone can edit that to "thumbs" that would be great!) I can't say that I really had a specific problem that I was trying to solve with my bike, but a couple of small things led me to try a JD kit for my bike. I was having trouble lofting front wheel off idle, it would die if I dropped it, it would die if I messed up and cut the throttle going up a steep hill... it had good power, it just seemed to have a somewhat brutal delivery. Screaming WOW would be an understatement when talking about how it changed the bike. The bike starts quicker, easier, idles better, won't stall when I drop it or cut the throttle on a hill, and pulls like a TRAIN in every gear from idle all the way up. It's buttery smooth too. The top end is insanely powerful to boot. A good example would be riding a long moderately inclined section of my fav trail. it's wide, kinda rocky. I used to go up in in 2nd gear really winding it out. I went up it yesterday in 4th right in the middle of the power. I was going faster, but felt much more in control. Following their recomended settings, I replaced the pilot with what appeared to be the same jet size (I say appeared.. it was a keihn with the same number.. I presume it was not modified by JD), the main went up a size (to 185), and the leak jet looked to be bigger... but I don't know. Used the blue needle with clip on 5th notch. I ride in Middle Tennessee... around 800-1,000 feet. Just wanted to share my excitement and results.