I was helping a friend change his oil on 06 FX160HO and we only manage to pull out 1 1/2 quarts of oil. After changing the filter, we only put in 2 quarts before it was just below full mark. We did everything according to the service manual which is warming up engine before etc. I have changed oil on a few Yami 4 strokes but never manage to pump out much. With the Ultra 250 I think every drip of oil comes out as I have gotten about 5 1/2 qrts out and top up with only 4 1/2. My Honda r-12x is the same thing, most of the oil comes out. It seems that a lot of the oil stays in the Yamaha's. Any tips on getting most of the oil out?