Need to know what is surging. Is the engine stalling? Is the engine running okay but the bike is slowing down erratically? As far as the substance in the air box, it may just be air filter oil, which is normal. If its a thick, sticky film it may be just that. If it looks like motor oil it's venting in from the crank case vent and may indicate worn piston rings. If it's gas it could be due to a flooding condition in the carb.
09 first run MudPro
Speedwerx 42# wet clutch springs
Secondary clocked to B-3
150 grams of Speedwerx rollers
Strobes from Pondtunes (should be worth 10hp right?)