hey im new to this stuff so here it goes. i got a 99 400ex all stock. it leaks oil between 2 of the upper jugs sections after riding and i cant figure out why. ive done gaskets and cranked it all down but still does it after about 40 minutes of riding. i was thinking about maybe just getting a bore kit but im not sure what works best and what not so i need to opinns. not doing a 440 though so its 416 or 426. also just wanna know what other simple upgrades i can do to give it a little extra kick. any help is appreciated!! thanks!

 

well im glad that nobody out of the 85 people who viewed this could help me lol