New Bike Discovery: Spot Brand’s Rocker SS 27.5+

Rocker SS 27.5+

Whether you call it 27.5+, B-Plus, or mid-fat, it all means the same thing: a super-fun four-season ride with more rubber on the dirt. Our new Rocker 27.5+ occupies that sweet spot halfway between fat bikes and cross-country bikes. It’s a do-it all size that makes you wonder, why did mountain bikers spend so many years on skinny tires? With plus you get the advantages of more volume minus the inertia and sluggishness of fat bike tires. We mount voluminous Rekon+ tires on wide Race Face rims, allowing you to run lower pressure for more grip and damping on chattery trails. The 30.9 seat tube fits the standard dropper post, and the Boost 148 rear axle gives you ample clearance plus a tight rear end. We added a red-hot Gates CenterTrack belt (with ISCG tabs for extra protection) to the Laguna Seca Blue steel frame for extra punch. Whatever the season or trail, the Rocker SS 27.5+ is mountain biking rock-n-roll boiled down to its purest essence. The Rocker SS 27.5+ retails for $2,500.

Reynolds 853 DZB Tubing

Seamless Air-Hardening Heat-Treated Steel with Double Butted Zones. The benefits of air-hardening steels are particularly noticeable in the weld area where, unlike conventional steel alloys, strength can actually increase after cooling in air immediately after welding. 853 is heat-treated to give high strength and damage resistance, and the steel properties allow thin walls to be used, so that lower weight but fatigue-resistant structures can be made. The chemistry includes carbon, manganese, chrome, molybdenum, silicon, copper. The interaction between the alloys result in a fine grain structure that forms with air-cooling without the traditional “quenching” (fast cooling in water or oil) process. High strength from bainitic phase steel after a series of cold-working operations. Heat-treatment to the 853 specification raises the yield strength for the entire tube, increasing dent and impact resistance.

Gates CenterTrack

Next-gen Carbon Drive System. Unique, super-strong, carbon-reinforced polyurethane system that requires no lube and provides a nearly silent ride. CenterTrack is stronger, lighter, more compact, and better at shedding debris than the prior Gates systems.

Dropout Modularity

Patented Kobe 2 Slider Dropouts allow belt-driven or chain-driven or geared configurations.

Boost 148 Rear Spacing

New standard to allow better clearance for short seatstays and big tires, plus a better spoke bracing angle for stiffer wheels.

110 mm Front Spacing

Better spoke bracing angle for a stiffer front wheel.

30.9 mm Seattube

Larger diameter seattube than most steel frames allowing compatibility with more dropper posts available in the market.

Tapered Steerer and Headtube

Stiff steering handling upfront.


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