Had an email asking about renting a bike on Kodiak. Didn't think it was possible but found out it is - for a price. 58 Degree North, an upscale sporting goods store on Mill Bay Road, rents nice mountain bikes for a daily rate. $35/day sounds like a lot but includes helmet and a lock.
If you've ever tried to find a parking spot downtown during Crab Fest, you'd understand that a bike might be a better alternative. And with so many miles of paved road (with a decent shoulder) there is a lot of places you can bike to and get away from it all.
The road from the Airport to town (take a right when leaving airport) is a tranquil drive in. It's the only place on the island with a speed limit of 55, so enjoy it while it lasts!