The KMV4 engine is longitudinally mounted in a steel-trellis space frame similar to what D
Pratt & Miller is an engineering powerhouse. Best known for its racing collaborations with General Motors—the firm developed the LeMans-winning Corvette C5-R and C6.Rs, the SCCA championship-winning Cadillac CTS-V, and more—the company also consults with, among others, the US Military, developing everything from “unmanned tactical wheeled vehicles” to ballistic missiles. With a remarkable amount of engineering talent and resources available—including the world’s most powerful privately owned supercomputer—Pratt & Miller is one of the most accomplished engineering companies in the world. What are they doing partnering with a tiny upstart American motorcycle manufacturer named Motus?
Birmingham, Alabama-based Motus, run by Lee Conn and Brian Case, the latter an industrial designer previously with Confederate Motorcycles, originally approached Pratt & Miller to develop the steel trellis frame and transmission for its MST sport-touring motorcycle. As the project progressed and the Pratt & Miller team became more impressed with the Motus effort and the opportunity it presented, the engineering firm transitioned from contractor to partner and eventually put the Pratt & Miller Engineering name on the MST prototype. That’s an endorsement.
That’s how we found ourselves at the Pratt & Miller facility in New Hudson, Michigan, just outside Detroit, where the Motus MST was revealed to the public for the first time. The sport-touring machine, intended to appeal to “aging” sportbike enthusiasts and American motorcycle fans who equally value performance and comfort, is as impressive as the location, showcasing clever design, fine craftsmanship and genuine technical innovation.
The Katech-developed KMV4 is the world’s first motorcycle engine to use direct fuel inject
The soul of this new machine is the 1650cc, liquid-cooled, 90-degree KMV4 motor. Designed and built by another top-tier GM supplier, Katech Engineering, the so-called “baby-block” V4 engine is closely related to the Chevrolet LS7.R small-block V8 that powers Pratt & Miller’s racecars, sharing the same basic two-valve, pushrod architecture. The juxtaposition of such a traditional engine design in a modern, sophisticated sporting chassis seems incongruent at first, but Case insists it’s complementary. The relatively simple KMV4 is light, weighing just 130 pounds, and without a heavy, complicated DOHC valvetrain located far above and away from the engine centerline, mass is centralized.
The engine uses the same direct-fuel-injection technology as the racecars, the first use of this sophisticated technology ever on a motorcycle. Instead of a conventional injector that sprays fuel into a throttle body, direct injection shoots an exceptionally fine, “digitally atomized” fuel vapor through the head and directly into the combustion chamber, producing very efficient and clean-burning combustion. As you might imagine given the engine’s championship-winning pedigree, it’s very powerful. Motus claims 160 hp and 122 lb.-ft. of torque near the 8000 rpm redline. With crankpins offset 75 degrees it’s got an arresting exhaust note too, more like a quick-revving NASCAR racer than any narrow-angle Honda or Aprilia V4.
A bevel gear arrangement transfers power from the longitudinal crankshaft to the compact, six-speed transmission, which incorporates a conventional, multi-plate, motorcycle-type clutch. The engine and transmission unit is unexpectedly compact, fitting easily within the 58-inch wheelbase. Seat height is 31.5 inches and the seat is exceptionally narrow at the front—not more than six inches wide, it looks more like a motocross seat—so it’s easy even for short riders to reach the ground with two flat feet. Multiple seat options will be available. With the cylinders canted forward 15 degrees and the transmission mounted low there is plenty of legroom. Ergonomics are “almost identical to Yamaha’s FZ-1”, Case says, and adjustable footrests and handlebars make it easy to alter the riding position to suit a wide variety of riders. Claimed wet weight is just 550 pounds, making it easy for average-sized riders to maneuver the bike, too.
Three-quarter coverage fairing features an electrically adjustable windscreen. If the head
Dual crank-driven counter-balancers keep things smooth, built-in Givi hard luggage provides carrying capacity and a six-gallon fuel tank should deliver state-crossing range, aided by overdrive gearing. Motus will offer two versions, a base-model MST and the premium MST-R, fit with premium Ohlins suspension, Brembo brakes, Marchesini carbon fiber wheels and all-carbon-fiber bodywork. Pricing hasn’t been set yet, pending final specification. Conn says it won’t be cheap, but he hopes to keep it within reach of motivated enthusiasts—presumably, well south of $30,000 for the base model.
The bike is undergoing final validation testing now. Case says that if all goes according to plan, the bike will make it into dealers as a 2012 model as soon as the end of this year. We see no reason to doubt that claim. The company has already come from wishful thinking to an innovative, original, all-new-from-the-ground-up prototype in just three short years. With prime movers like Pratt & Miller and Katech on their side, they are well positioned for the final push to market. We can’t wait for our first ride.