Maybe a strange question, but here goes.......I changed the engine oil in my bike yesterday. I use Mobil 1 V-Twin. My bike takes 4 qts (actually 3 1/2). Anyway, I have 1/2 qt. of Mobil One left over, and I want to change my primary oil today. I use Formula + in the primary, which takes 38 ounces, or 1 qt., 6 ounces. My question is this...instead of buying a whole extra qt. of Formula + to get the extra 6 ounces, can I use the extra Mobil One oil I have left over, and mix it with the Formula + to top off the primary? Will it "mix" OK, or would that be a no-no?