[Previous entry: "American Chopper Collectables"] [Next entry: "Charity Ride for Milward"]

07/11/2005: "Boost Brothers - Triumph Rocket Roadtest"

Turbo Connection turns a Triumph Rocket III and a Harley-Davidson V-Rod into true boulevard badasses
Written by Roland Brown , Brian J. Nelson, article taken from motorcyclistonline.com

Triumph’s Rocket III mega-cruiser is supposed to be electronically limited to 140 mph, but it sure doesn’t seem that way right now. As I glance down at the speedo and watch the needle blow past the 140-mph mark and into the off-the-scale white zone beyond, the open-pipe, turbocharged triple just keeps howling and accelerating as I tuck behind its flyscreen to keep from being blown off the thing.

Moments later I have to slow for traffic, and my chance to feel the Triumph bashing up against its rev limiter in top gear—as it was about to do—is gone, and gone for good. Daytona’s streets are clogged with bikes and police, and I don’t need to be reminded that the last time I rode a turbo-bike here it cost me $250 after being speed-trapped at just over 100 mph. And the world’s first Rocket III turbo has the horsepower to be a whole lot more expensive than the Bonneville I was riding then.

The Hinckley-built triple is seriously fast in stock form and has sold quite well since its introduction two years ago. But some were disappointed its massive, 2294cc triple was tuned more for flexibility than balls-out performance. The Rocket makes a respectable 132 rear-wheel horsepower and a whopping 141 pound-feet of torque, but it isn’t half as scary as it looks. Some might say it looks a bit tame.

Bolting on a turbo from Turbo Connection changes all that. Running just 8 psi of boost on standard pump gas, this Rocket III routes 202.8 horses to its rear tire along with 215 pound-feet of torque. Turbo Connection boss Brian Olson can’t help grinning when he talks about the bike, which was like a Hinckley factory gift to someone specializing in turbocharged Triumphs. “It’s just a beautiful turbo motor,” says the man from Rapid City, South Dakota. “As well as its size and three-cylinder smoothness, it has low compression, just 8.7:1, which is what you want [when turbocharging], and a strong bottom end. It even has twin plugs per cylinder, which helps combustion. As soon as I saw it I knew it would be ideal [for a turbo].”

Olson should know. He’s a 33-year-old motorcyclist and engineer who began turbocharging cars in the late 1980s, progressed to 200-horsepower turbo snowmobiles and then concentrated on Triumph triples after founding Turbo Connection in 1992. His blown Speed Triples and Sprint STs have been producing a Hayabusa-beating 160 bhp for years, but the Rocket III offers a dramatically different level of performance.

Olson says developing the Rocket kit was relatively straightforward. The turbo is from New York-based iBoost, formerly Aerocharger. The unit differs from many turbos because it’s a variable-vane unit, meaning boost is controlled not by a wastegate but by adjusting the position of the turbo’s vanes. For more boost they’re closed up; for less they’re opened slightly to allow more exhaust gas to escape straight into the exhaust.

The compact iBoost turbo unit lives below and behind the Rocket’s gargantuan inline triple. Even with a relatively conservative 8 psi of boost, it turns the volume all the way up to 203 horsepower and 215 pound-feet of torque.

Olson fitted the compact turbo beneath the huge engine, where it’s barely visible at first glance. His kit includes everything needed to get the bike running with “about a day’s work for a typical owner,” according to Olson. Besides the unit itself there’s a special aluminum airbox, a stainless steel exhaust system and a boost computer to monitor the fuel-injection system.

The Triumph’s burly bottom end, lightly stressed in stock form, is more than capable of handling the extra performance, Olson says. His only strengthening mod is to fit stiffer clutch springs, included in the kit. Even so, lever action is surprisingly light as I climb aboard and press the starter button, setting the motor alight with a slightly high idle and a deep and very loud burble from the slash-cut silencer.

If my first impression is of how docile and normal the turbo-Rocket feels as I maneuver it from a parking lot out onto the street, the second is exactly the opposite—because this bike is just crazy fast.

From a walking pace in first gear, a crack of the throttle has the front wheel leaping into the air in a way no long-wheelbase, 803-pound motorcycle has a right to. This bike is way quicker off the mark than the standard Rocket, itself one of the world’s hardest-launching street-legal motorcycles.

Equally impressive, the engine doesn’t suffer from turbo-lag. The iBoost’s design, doubtless helped by Olson’s plumbing experience, has virtually eliminated lag. Boost is always available to send the bike rocketing forward at the touch of the throttle. That awesome, 200-plus peak horsepower is produced at 5500 rpm, with maximum torque arriving at just 3750. Those numbers come at higher points on the scale than the standard Rocket’s peak numbers, but the blown bike’s curve is far higher along the chart from just off idle all the way to the 6500-rpm rev limit.

And it certainly feels that way. From almost any engine speed, hard acceleration results in a riot of blurred scenery and frantic gear-changing to avoid running out of revs. The roar from the slash-cut pipe makes it feel even faster. The drainpipe-like, 90mm-diameter tailpipe comes standard with the kit, but Olson offers a quieter unit if requested.

This black bike’s flyscreen and stepped Corbin seat aren’t included in the kit, but I was glad of the way they kept me aboard as the Rocket demolished every vehicle it encountered on the straight roads in and around Daytona. Having the aerodynamics of a small building doesn’t matter when you’ve got this much power at the end of the cable.

Olson left the Triumph’s chassis standard, which isn’t a problem. The Rocket stays plenty stable under ultra-hard acceleration, even while cranked over on the few fast corners I find. Thankfully, the bike’s triple-disc brakes aren’t fazed by all that speed and weight. And the fat rear Metzeler does a pretty good job of putting power to the ground. Rubber and fuel costs would be considerable if this bike was used as its maker intends. But at least the kit’s $5395 price is reasonable.

My test ride was relatively short, which is probably just as well given this bike’s performance and my previous dealings with the Florida Highway Patrol. But the memory of the Turbo Rocket will linger long.