Barking-Mad Bonnie
Barking-Mad Bonnie
QUIET RIOT SPECIAL SECTION
Big cylinders, big carbs, big surprise
MARK HOYER
IT SEEMS LIKE A DELUSION, SOME SICK SLEIGHT OF hand, the way this neo-retro built-up Bonneville accelerates. You find yourself asking, “Hey, can I smoke this Mille off the line?” Unthinkable as alchemy aboard the stock bike, but damned if the unnatural powers crammed into the engine cases by South Bay Triumph don’t make it happen! Loudly, too!
Okay, this Bonnie is a bit too barky to be considered a “sleeper,” but the vintage visage-complete with factory Union Jack paint scheme-is more than enough to make up for it. Just ask the poor sap in the Mustang 5.0 who just had his eardrums blown out and his musclecar blown off by this pumped-up Bonneville. “That’s much quicker than Grampa’s Tl20,” I think he said, sucking fumes.
It rips. The way the bike revs and the crack and roar from the reverse-megga shorty exhausts makes it sound as though it’s ready for the 1969 Daytona Short Track. But this 944cckitted parallel-Twin is meant for terrorizing more mellow miscreants on Main Street. Hey, it’s why we modify things.
You understand now that it is loud. Also understand that this Bonnie has got a meaty, super-torquey lunge that feels a lot more like big-block Harley than some bigblock Harleys. There’s plenty of mass inside the motor, plenty of motor to spin up the mass, and bike-builder/ South Bay boss Matt Capri (www.southbaytriumph.com) even added a tooth to the countershaft sprocket to mellow things out at high-speed cruise. But droning along suchlike is a complete waste. Romping through the bottom three gears is so much fun, you really dig red lights-at least the ones over intersections.
So, moving is this bike's forte. Idling is a necessary evil brought about by unthinking traffic engineers and overpopulation. But idle we must, and this 94 x 68mm motor with its great-lump cams and giant 42mm Mikuni flatslides spits back defiantly at a standstill. My friend Ray, who fixes Jaguars for a living and collects cranky old Britbikes for fun, said, “Anybody who’s ever had a throttle cable attached to Amals will understand that you need to blip the throttle on a British bike.” It is pleasing to the earplug-wearing pilot to do so at stops.
“We need to go up in size on the pilot jet to stop that popping,” Capri says, “but it kills the mileage.”
Mileage?
Capri has been power-mad most of his life, and he likes building big bhp using unexpected motorcycles.
“I love being the underdog,” he says.
Capri’s been to the Bonneville Salt Flats on a BMW K100 and Triumph Daytona 1200, for instance, and broke the double-ton on them, setting records in the process. He just turned 60, and speaks enthusiastically about how good he’s getting at wheelies.
And yet he can immediately roll into technical discussion about rod angles, lobe centers and flame speeds, which is when my eyes glaze over and I ask him about wheelies again.
Capri nonetheless relates that this Bonneville’s compression is nudged to 10:1 with flat-top pistons. Cams get the fabled #2 grind (Huh? “It’s our second attempt,” Capri offers happily), and the flowed cylinder head and CNCmilled intake manifolds are port-matched. It must be a pretty magical combination, because you’re looking at about a 30horspower jump over stock. Our last Bonnie testbike made 56 bhp, this one here bangs out 85. That’s a more than 50 percent increase. To plagiarize a fellow staffer’s comparison, that’s like a modified Hayabusa making 240 bhp. Awesome. Torque picks up about 20 foot-pounds to twist out a healthy 64 ft.-lbs., or only a few lubs shy of the Aprilia Mille to which you just showed your (custom circa 1969) taillight across the intersection. Except the Bonnie delivers its best torque about 2000 rpm sooner.
“There’s more left, too,” Capri says. “We haven’t been able to defeat the stock rev-limiter. I know with the Daytona valve springs and stuff we’ve got in there we can rev this thing to 11,000 rpm, no problem. And I’m working on a 1080cc version now.”
Oooh, Blimey! Almost seems like a bargain with bike and mods at $14,500, “including tax, license, freight and setup,” he says with a smile. For that price you also get the wide rear wheel with a 180mm meat, Works Performance shocks and a re-sprung fork.
Sure, just like with a stock Bonneville the front brake lever feels like you’re squeezing the “creme” out of a Twinkie, the clutch more and more behaves as though the plates are made from banana peels (despite stiffer springs) and the engine idles like it’s got whooping cough. On the pipe, though, this thing sings like Pavarotti, or some English tenor who smokes a lot and whose name we don’t know.
But sing it does, and as long as the clutch hangs on (no more wheelies, I swear!) and I don’t splat into the rear end of a trash truck, I’ll keep filling its lungs with fresh air and my bloodstream with adrenaline.
Rumors abound about Triumph’s giant three-cylinder 2.2liter power-cruiser. Hey, Hinckley, here’s your power-cruiser! This thing’s a scream. Well, more of a throaty growl.
