Hey, today I cleaned two twin-air filters that had the bio oil applied. I was using 100ml of the twin-air bio soap and three liters of hot water. The first one wasn't very dirty and came out almost spotless, except there was still alot of oil left in the filter. I kept cleaning it but couldn't get all the oil out. Finally had to use the Maxima filter oil cleaner to get the rest of the oil out. The second filter was used at a dusty track for a couple of hours and was quite a bit dirtier. Same result only this one didn't get as clean. Still had to use the Maxima. Is there a trick to using this stuff? The oil worked awesome, nice and sticky, but I'm not that impressed with the soap. The reason I went this way was that I was having difficulties cleaning the Maxima oil out of my filters. Also, the Maxima oil cleaner is real stinky and ends up pissing the old lady off every time I use it. No matter how careful I am, she says she can smell it all over the house...my bike lives in the basement. Please advise... Jay.