Stylie, if you're worried about your a/f ratio being affected, don't be. Everytime you ride your bike for a few minutes at easy load (flat ground, 2000-4000rpm steady) the ECU is in its closed-loop mode and reevaluates the mixture. Any changes in atmospheric temperature/pressure, or something like the lack of CO2 from a crank case breather is accounted for by an adjustable 'multiplier' called the AFV - adaptive fuel value, which will try to return the mixure to stoichiometric (chemically balanced).