Salsa Heyday! C Frameset - Carbon Black SmallSalsa Heyday! C Frameset Carbon Black Small. The Heyday! is Salsas most versatile fat bike designed and engineered to excel in the wide variety of conditions. The frame utilizes 197mm rear spacing to accommodate up to 5" tires and the 100mm threaded bottom bracket allows a wide range of crank (Q factor) choices. Alternator 2. 0 dropouts allowing for some of the shortest chainstay lengths available easily supporting single speed or geared drivetrain