I would say it would depend on how you are operating you bike and what model and year.
A general rule for me if I'm not riding like a bat out of hell ( which I often do ) is on my old S4Rs would be 20 miles at best.
Just the other day I was on my 1098 R and riding very aggressively and I happened to notice the low fuel light was glowing.
I immediately headed for a town for gas.
It had been 100 miles since my last fill up so I wasn't taking any chances since I was out in the " hills ."
Luckily I found a gas station in 15 miles. Whew.....
Dolph
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