Bill Ryan drew the first Supercross frame in 1989 after watching gate starts from behind the gate — rear triangles flexing so badly that chains drooped a quarter inch every time a rider loaded up. The fix became the six-bar.

The Story

The frames of the day couldn't take a hard gate start. Steel-mill tube sizing limited how stiff a conventional rear triangle could be, so Bill lowered the first set of seat stays and welded in a second set for extra triangulation. The result was stiffer, faster accelerating, and better handling than anything else on the market. That six-bar rear end ran on Supercross cro-mo and aluminum frames for more than a decade.

The geometry started from what riders complained about on the Free Agent Limo — a rear triangle a touch too short and a head angle a little too quick. The first frame was welded in a single day by Brent Shoup, painted black with neon green rear stays and dropouts, and validated with a 30-minute test ride by Billy Griggs. The frame was built for AA Pro Billy Harrison — who also named the company, in a 2 a.m. phone call from a national.

Production frames ran full seamless 4130 chromoly with the Star Products "Fish Head" dropout, set up for sidepull brakes with a 1" threaded head tube and an American bottom bracket. Every frame and fork was chrome plated; plating rejects were powder-coated black, red, or blue and sold that way. A frame and fork set cost $139.95 in 1989.

In 1992 the frame switched to cantilever V-brakes and a 1-1/8" threadless head tube — a few rare transition frames ran a 1" threadless fork first — and the frame and fork set moved to $189. Tange tubing experiments began the same year, and by 1997 Supercross was building around 500 frames a month across the line.

By 1994 the SX250 was also rolling out of dealers as a complete bike. BMX Plus! ran a spy photo of the '94 Supercross XLT — the factory Team model, built on the SX250 frame and fork — on page 20 of its August 1994 issue: contoured aluminum Supercross Strongarms, Peregrine Power pedals, chrome Peregrine rims on sealed hubs, a Pro Neck Pro 3 stem, and an Odyssey Pitbull, with a Tech numberplate and Rad Accessories padset stock. "All factory Supercross crazies ride the XLT," the magazine wrote — around $699 complete. The XLT shipped in both SX125 Pro and SX250 Pro XL sizes; the 20-1/2" top tube the magazine quoted was the Pro size.

“The average frame back then would flex so bad you would get a quarter inch of chain sag just by pressuring the gate.”Bill Ryan, founder

Specifications

Who Raced It

Built for 1989 AA Pro Billy Harrison. Raced through the era by James Prichard, Kevin Gentry, Ray “The Denver Destroyer” Luscombe, Todd Steen, John Gonzales, Steve Spencer, Eric Jones, Jason Donnell, Zack Roebuck, Turnell Henry, Eddie Livingston, JP Fellin, Stephanie Anderson, and Ronnie Chalk.