Since the early fillet-brazed frames of Salsa Cycle's heyday, the brand has enjoyed success in niche markets with its cyclocross, commuter, 29-er and steel hardtail frames. But Salsa has developed two new frames—one built around 26-inch wheels and the other 29ers—that should have mainstream riders salivating. The El Kaboing and Big Mama may have colorful names, but the 4- and 5-inch travel trail bikes are engineered with many innovative features.
The frames are built from custom-drawn, size-specific Scandium-alloy tubes and all forged parts. Salsa is a proponent of Scandium, which offers better yield and tensile strength compared to traditional aluminum, and allows the company to build a lighter and stronger frame than one made from standard 6061 or 7075 aluminum.
Upon first glimpse, the El Kaboing and Big Mama appear to use a conventional single-pivot with bell-linkage design, however further inspection reveals a twist. The new bikes have no rear pivot. Instead, the seatstays are made from a flattened Scandium tube that flexes as the wheel moves through its travel.
Flex stays reduce weight, eliminate a high-stress fastening point from the frame and increase rear triangle stiffness compared to a pivot. Additionally, the flex stays provide progressive resistance that helps reduce pedal bob. Salsa claims that the stays are durable and has evidence to support that claim: The stays flex considerably less (5 millimeters on the Big Mama and 8 millimeters on the El Kaboing) than the chainstays on the company's Dos-Niner softtail, which flex 25 millimeters and have proven to be quite reliable.
Rear dropouts rarely get as much attention as those on the Big Mama and El Kaboing. Weld areas between the forged dropouts and the Scandium tubes have been maximized for strength. The dropouts on both sides are easily replaceable using basic chainring bolt hardware. The bikes also use a post-mount design to attach the rear brake caliper. The unique system accommodates 160-millimeter rotors sans adaptors.