S&M BMX Mad Dog Frame

The Mad Dog is Chris "Mad Dog" Moeller's signature frame, reissued 36 years after the original for riders who prioritize lightweight construction with disc brake compatibility. Features sub-5 lb weight, 10" standover height, and disc mount designed for 120mm rotors. Built with engraved Shield on headtube, engraved '87' on bottom bracket shell, and Mad Dog tag on seat tube. Made in the USA and available in seven top tube lengths from 20.5" to 22".

Key Features

• Sub-5 lb frame weight – At 4.9 lbs, provides competitive weight for trail and track riding without sacrificing strength or disc brake functionality
• Disc brake mount with adapter system – IS-mount disc tab designed for 120mm rotors with 0mm IS-to-post adapter, or 140mm rotors with 20mm adapter; narrow-flange hubs (Profile or similar) recommended for spoke/caliper clearance
• 10" standover height – Tall standover provides increased clearance for manual-heavy riding and aggressive body positioning on trails and jumps
• Seven top tube options – Available in 20.5", 20.75", 21", 21.25", 21.5", 21.75", and 22" lengths to accommodate wide range of rider heights and preferences
• Traditional 110mm rear spacing with 3/8" dropouts – Standard BMX hub compatibility eliminates need for specialized disc-specific wheels
• Slotted seat tube for traditional or quick-release clamps – Accepts standard 28.6mm seat clamps or QR designs without integrated clamp hardware
• 74.25° head tube angle and 13.9" rear end – Geometry balances stability for high-speed trail riding with responsive handling for technical lines
• Engraved graphics – Permanent Shield logo on headtube, '87' on bottom bracket shell, and Mad Dog tag on seat tube won't wear off like decals

Technical Specifications

• Top tube lengths: 20.5", 20.75", 21", 21.25", 21.5", 21.75", 22"
• Rear end (chainstay) length: 13.9"
• Head tube angle: 74.25°
• Seat tube angle: 71°
• Bottom bracket height: 11.6"
• Standover height: 10"
• Head tube: 5" tall integrated campy-style
• Bottom bracket: Mid
• Dropouts: 3/8" with 110mm spacing
• Brake mounts: IS-mount disc (120mm rotor with 0mm adapter, 140mm with 20mm adapter)
• Seatpost size: 1" (25.4mm)
• Seat clamp: Slotted for 28.6mm clamp (not integrated)
• Maximum sprocket: 39T (with proper chain alignment)
• Frame weight: 4.9 lbs
• Made in: USA

Compatibility and Ideal Use Cases

Requires integrated campy-style headset, mid bottom bracket, 110mm rear hub spacing with 3/8" axle, 25.4mm (1") seatpost, and 28.6mm seat clamp. The disc brake mount works with hydraulic or mechanical disc systems using IS-to-post adapters and 120-140mm rotors; narrow-flange rear hubs (such as Profile Racing) recommended for adequate spoke-to-caliper clearance. Maximum 39T sprocket maintains proper chain alignment without interference. Best suited for trail, dirt, and track riders who want disc brake stopping power, lightweight construction, and tall standover for aggressive riding. The 74.25° head angle and 13.9" rear end provide stable handling for high-speed sections while remaining maneuverable for technical lines. The 20.5"-22" top tube range accommodates riders approximately 5'6" to 6'2" tall, though individual fit preference varies based on riding style.