ok i have a cbr 600 f4 the other day it died on me but i got it running again but when i put all the ram air tubes on it ran like **** in about 4 to 8 grand then it clears up a little but i took off the tubes thinking it was getting to much air or something which i dont know but it ran better i check the plugs and they look a little dark and they got 20,000 miles on them so yea could it be may carbs or anything else when it ran like **** it sorta bogged down and back fired alittle so could it be the plugs are bador what any help would be great