Marin Alcatraz 2 Frame Kit ( Red Purple)

The frame is made from Series 3 6061 aluminum and built around 26-inch wheels. According to the manufacturer, it combines low weight with the toughness needed for aggressive riding, and its geometry was fine-tuned with Matt Jones. Short chainstays are intended to make manuals and pop easier, while the low, compact frame shape supports a freer and more responsive ride feel.

From a technical standpoint, the frame kit uses 135×10 mm horizontal dropouts, a 73 mm threaded BSA bottom bracket, and ISCG 05 tabs for chain retention devices. Internal cable routing helps keep the build clean and reduces rattle. Marin also includes useful finishing parts in the kit: an FSA No 57E headset, a Marin Chain Tension Device, and a Marin MTB bolt-type seat clamp.

Marin Alcatraz 2 Frameset suits riders who want to choose their own fork, wheels, cockpit, and drivetrain around a proven dirt jump platform. It works well for riders building a first serious custom DJ bike, as well as for experienced users looking for a light, stiff, and durable frame for pump track and street riding.

Key features and benefits

• frame kit for dirt jump, street, pump track, and slopestyle
• Series 3 6061 aluminum construction
• built for 26″ wheels
• geometry fine-tuned with Matt Jones
• short chainstay concept for a more responsive ride
• 135×10 mm horizontal dropouts
• 73 mm threaded BSA bottom bracket
• ISCG 05 tabs
• internal cable routing
• includes FSA headset, Marin Chain Tension Device, and Marin seat clamp
• available in short and long sizes

Who is this product for
Marin Alcatraz 2 Frameset is for riders who want to build a dedicated custom bike for jumps, tricks, and technical riding. It is a good fit for dirt jump, street, pump track, and skatepark riders who prefer choosing their own parts instead of buying a complete bike. The short size is intended to feel more BMX-inspired, while the long size offers a calmer ride feel; Marin states that the long frame fits riders 5’11” and taller.

Specification

• Frame: Series 3 6061 Aluminum, 26” Wheels, 135x10mm Horizontal Dropouts, 73mm Threaded BB, ISCG 05 Tabs
• Headset: FSA No 57E, Semi-Sealed Cartridge Bearings, 1 1/8″ x 1 1/2”
• Extras: Marin Chain Tension Device, Marin MTB Seat Clamp, Bolt Type
• Sizes: short, long
• Color shown on the manufacturer page: purple / red

Size guide

• Short – more compact, more BMX-inspired ride feel
• Long – calmer ride feel; Marin states this size fits riders 5’11” and taller