A twin-engine CB750 land-speed racer from the late Boris Guynes…
If our trip to the 2022 Bonneville Motorcycle Speed Trials taught us anything, it’s that the Bonneville Salt Flats are a truly special place — a unique vortex where epic scenery, ingenuity, friendship, and speed come together like no place else on earth. It’s an atmosphere that has to be experienced, heady with methanol and mind-bending creations.
One of our favorite Bonneville builders is the late Boris “Bob” Guynes. Born in 1937, he was an Army veteran, fabricator, and racer who spent more than 60 years building and racing motorcycles. Not only did he set records at Bonneville, but he even raced in the Isle of Man TT in the 1960s. Says one of his friends from the Classic Japanese Motorcycle Club (CJMC):
“Bob was one of the founding members of the club. He was an amazing fabricator and an artist. Motorcycles were his canvas. He one many awards at bike shows for the bikes he built. He built a bike that set a world record at Bonneville in 2011. He had a big heart and would help anyone.”
He was particularly well-known for his incredible salt racers. At Mecum’s motorcycle auction last month in Las Vegas, a number of custom-built machines from The Bob Guynes Collection crossed the auction block. So we’ve decided to highlight some of his builds.
The machine you see here is the “Anti-Christ,” his 1972 Honda 750 twin-engine salt flat racer powered by a pair of modified CB750 engines! Says his son, Lawrence, of the build:
“The Double 750cc was meant to make a statement at Bonneville that he’s not playing around. Only a few riders had the courage to ride a homemade frame monster like that.”
Lawrence says that his father wanted to complete a build that even Honda engineers would never dare to attempt.
“The massive machine joins the superbike engines together in a hand-fabricated, steel-tube frame. Four outboard carburetors with velocity stacks on custom intake manifolds feed fuel and air into the engine, which sounds off through an eight-into-four, side-exit, track sweeper exhaust. A dry-sump oil system with an externally vented catch can keep all eight cylinders and
32 16 [Ed.] valves turning and burning.” –Mecum
Slowing this 1000-pound home-built monster is the job of some massive four-shoe vented front drums, while an early Honda 450 twin fuel tank holds just enough gas for high-speed flat-out runs on the salt.
Unfortunately, we haven’t been able to track down any specific numbers on the bike’s speed on the salt. If anyone knows, please don’t hesitate to comment below or email us.
If you’re interested in owning this piece of Bonneville history, it’s unfortunately too late. The Anti-Christ sold for $7150 at the recent Mecum auction — about what you’d pay for a nicely restored original CB750.