There is a 2nd & New Bike hire on St Mary's is bookable by calling : 01720 422786 or by emailing: enquiries@bookabikeonscilly.co.uk.
The bikes are dropped off & picked up from your accommodation for convenience. Check out their website: www.bookabikeonscilly.com
I've also placed a link to their website in the link list on the right side of the page.