S&M Mad Dog 990 BMX Frame

S&M Mad Dog 990 BMX Frame

The Mad Dog 990 is Chris "Mad Dog" Moeller's signature frame with chainstay-mounted 990 brake compatibility, reissued 36 years after the original. Features sub-5 lb weight, 10" standover height, and traditional 990 brake mounts for riders preferring U-brakes over disc systems. 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 six 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 brake functionality
• Chainstay-mounted 990 brake mounts – Traditional U-brake bosses welded to chainstays for riders who prefer 990-style brakes over disc or V-brake systems
• 10" standover height – Tall standover provides increased clearance for manual-heavy riding and aggressive body positioning on trails and jumps
• Six top tube options – Available in 20.5", 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 works with conventional wheelsets without specialized hardware
• 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", 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: Chainstay-mounted 990
• 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, 28.6mm seat clamp, and 990-style U-brakes if running brakes. Maximum 39T sprocket maintains proper chain alignment without interference. Best suited for trail, dirt, and track riders who prefer traditional 990 brake feel and modulation over disc brake systems, or riders building period-correct setups with modern geometry. 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.