Compression

[baker400ex]

I have an 06 400ex and for sum reason it sputters out real bad in second gear and i cant think of any reason for it being like this, it has a K&N, slip on hmf, and a stock airbox and its jetted correctly from the looks of the spark plug. is there any reason engine compression would have 2 do with this problem, also my throttle responce is horrible. Any Suggesions ? please and thanxz for your suggestions

[GPracer2500]

Your jetting is probably off.

If you think you've lost compression then get a compression tester (you'll need a 12mm thread adaptor) and check it.

[rooster300ex]

What is your carb setup. fuel screw,mainjet,needle