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no bottom or top after engine mods 250X

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I have an '06 CRF250X that I just put an '07 CRF250R head on it with Ron Hamps coated intake valves. I also put in a JE 13.5:1 piston in it as well as a Crower Victory Cam. Now the bike has virtually no bottom end and no top end (acts like it is starving for fuel at times as well)....but pulls HARD at midrange. A friend gave me an '08 CRF250R cam to stick in it just to make sure there is nothing wrong with the Crower...the reason we suspect the Crower may be part of the problem is because the timing marks are off by a full tooth, and may be off by quite a few degrees as well. I'm hoping it's actually just a jetting problem though. Any thoughts as to what I may need to do jetting wise? I'm guessing putting in a larger main jet and raising the needle? Bike starts right up at the touch of the magic button and idles just fine....and seems to rev pretty well when bike is in nuetral, sometimes it will bog for a split second if I which the throttle quickly...it's just when the bikes is under load that it seems to have issues. Any suggestions would be greatly appreciated:thumbsup: :)

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