I have designed balck & white and full color t shirts. You can order them through Zazzle one at a time for your members to wear. These could be great for bicycle shop owners. The advantage is that you don't have to keep an inventory. Zazzle does offer volume discounts on all of its products.
The text on this and all designs can be changed. It is also easy to change content, fonts, size, placement, text color and so on.