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Okay, at age 49.75 (approximate) I realize I'm probably "the kid" here. So here goes:

I keep seeing references to pie in this forum. I am confused. What are you gents referring to? is it:

Store bought pie, like Mrs. Smiths?

The kind of pie your better half makes for you, while you're out and about riding?

The Mathematical Pi? 3.14159265358979?

Or, the kind of pie that, uh, doesn't cause tooth decay or unwanted weight gain?

I am very, very confused. Thank you.