Among the giant, twin-cylinder desert sleds that ruled the Southern California desert racing scene in the mid- to late-1960s, Triumph’s TR6 is the undisputed king, but, for a moment Norton’s P11 was more than a match for its British rival.
Built from 1967-69, the 750cc P11 was both beauty and beast. It was developed strictly for the exploding U.S. motorcycle market, but the P11 owes its roots to Norton’s Atlas streetbike model of the time.
California Norton Distributor Bob Blair built the original P11 prototype, mating the Atlas 750cc twin cylinder engine in a Matchless G85 CS (Competition Scrambles) Reynolds 531 lightweight steel frame that shared some design attributes with the aftermarket Rickman frames that were popular with the motocross and off-road twins racers of the day. Blair worked to save weight everywhere he could to give the P11 a competitive power-to-weight ratio, a goal exemplified by the P11’s tiny, Candy Apple Red alloy fuel tank. Power output from the booming twin is reported to have been in the 52-horsepower range.
The prototype P11 was given to successful AMA District 37 desert racer Mike Patrick for testing. Patrick recalls his experience with the P11 in his “My Own Words” autobiography on The Banner Is Up website, a haven for classic So Cal desert racing stories, photos, records and statistics.
“Tom ‘Tiny’ Maxwell and I took the prototype out to the desert for a week of bashing, and the bike worked perfectly,” Patrick wrote. “I was nursing a shoulder from a crash, and Tom and I took a week off and went to the desert to run the crap out of it. They were in a hurry to send it back to England. I tried to race it that Sunday, but the difference in racing and what we call cow trailing is not even in the same world. I made it to the smoke bomb and had to stop, my shoulder was killing me. We were supposed to get the bike back to ZDS Motors so they could ship it back to England and get started on the new units. I tried to race it, but my shoulder was killing me, so I put the prototype in the truck and took it back to ZDS and told Bob Blair not to change anything. Guess what? They did, but it was ok.”
Indeed, the changes made to the P11 weren’t all that drastic, as they were more to streamline production than anything else. The small alloy fuel tank remained, but the magneto ignition on the P11 prototype was replaced with a twin coil capacitor ignition, and production Amal concentric carburetors replaced the monobloc carburetors on the prototype. The P11 was also fitted with a speedometer and tachometer and an alloy sump guard.
Upon hitting U.S. shores, the P11 carried a relatively high price tag of $1339, and according to AMA Hall of Famer Tom White, curator of the Early Years of Motocross Museum, Norton’s lack of popularity compared to BSA and Triumph led to poor sales.
Even so, the bike proved to be competitive off the showroom floor if not on it, as Patrick rode a Norton P11 to the Heavyweight points championship in the desert in 1968. However, the P11 enjoyed a very short reign in the desert. The scene was already changing as the fire-breathing twins that roamed the Southern California desert were encroached upon by smaller, lighter and quicker two-stroke machines.
“The big P11 was an arse kicker, and I won lots and lots of races on it,” Patrick said. “[But] when the two-stroke thing came in on the scene, I had no choice but to change. With a tear in my eye I parked the desert killer…Nothing is, or ever will be, a match for the big Norton sailing across the desert.”
The P11 was replaced in 1968 by the P11A, which was more of a street going machine with low pipes, more weight and a lower the cost. Today, P11s are highly sought after by motorcycle collectors.
Norton’s time at the top of the American off-road scene with the P11 may have been brief, but it certainly is memorable.