I have a softail with split tanks and a fuel petcock that has "on" and "reserve" I've been running it in the "on" position but it seems to have been draining from both tanks. I try to stop at least every 110-120mi and check both. My question is. Should the "reserve" be my secondary tank? I'm thinking my petcock might not be switching correctly. I fotgot to add.. It seems to drain more out of the right side tank in the "on" position than the left side, but not much. Shouldn't the reserve be the one sucking out of both tanks?