Like a centipede or the judicial system, a bicycle relies on the synchronicity of its many parts. Bring harmony to your riding with today’s Groupon to Santos Bike Shop. Choose between the following options:

• For $25, you get $50 worth of rentals or merchandise.
• For $39, you get a premium bicycle tune-up (an $89 value).<p>

The pedal experts at Santos Bike Shop pair shoppers with loaner two wheelers and quality gear and fix up bicycles to ensure their road- and trail-worthiness. Among the Giant bikes available for rental, the Revel 1 ($25/day, $200 deposit) sports a lightweight ALUXX aluminum frame, and the patriotic Anthem X 3 29er’s ($45/day, deposit is cost of bike) 29-inch wheels and Maestro suspension inspires bald eagles to fly in victory lap formation. Protect noggins with Giant Talos helmets ($44.99) and keep hands shielded from handlebar burn with a pair of Spenco T.2 Elite riding gloves ($49).

A complete premium tune-up trues wheels and tensions spokes, and adjusters work over the shifters and brakes. The bottom bracket and hubs are left taut and greased, and all cables glisten with a fresh coat of lube. Finally, the whole bike receives a cleaning and polishing, leaving it ready for appearances in glitzy bicycle beauty pageants.