Breakfast at the Red Eye, pedaled some thirteen+ miles, and lunch at the Brew Pub, (honey-smoked turkey, applewood bacon, and brie on sourdough, washed down with a pint of the house IPA...)
The weather is positively gorgeous: Low 70s, low humidity, severe clear, not a cloud in the sky. The kind of day that just makes you grin like an idiot and wave at complete strangers.
There are two bicycle shops right on the Monon. Only one is open on Sunday. Does this make sense to anyone?
Look, the people who can afford to buy stuff in your shop probably work for a living. When do most people work? That's right, Monday through Friday. This means that they are out riding their bikes on the busiest bike trail in the city on what days? That's right, Saturday and Sunday.
So for half of the heaviest traffic days on the Monon Trail, (which runs within 100' of your door, remember,) you are closed.
Are you attempting to cater to the unemployed? Because that doesn't strike me as the soundest of business models.