I will be changing my oil in my bike this week using torco blend. My dealer supplies it free of charge. But only every 6k miles and i want to change it every 3k. So i need to buy oil every other change. But because torco isn't available around here i was thinking of using motul blend. I hear it's great oil everywhere i read about is, plus it's much cheaper than the Torco blend. But the thing is, my bike takes over 4 quarts (1.1 gallons) and the motul comes in 1 gallon jugs where i'd be getting it just up the street from me. They don't have it in the quart bottle. I suppose i could find it elsewhere and buy a separate quart, but theres probably almost another $10 and i only need about .3-.4 quart. (thats what i took last time when i drained it really good)So would it be bad to change to motul and leave about a third of a quart of the old torco in it?