Meet the Motus
MEET THE MOTUS
ROUNDUP
American-made V-Four sport-tourer breaks cover
HARD TIMES BRING CHANGE. Currency shifts are making Japanese goods less attractive, European goods more so. How about U.S. goods? Maybe it's time for a new motorcycle enterprise.
Here comes Motus (Latin for "motion"), with Made in USA all over it. When I logged onto the Motus website (www.motusmotorcycles.com), I read, "Engineered in Michigan, designed and built in Alabama." Engineering is by Pratt & Miller, a firm with 20 years of racing and other design experience, long allied to General Motors.
I spoke with Brian Case, VP and Design Director. I learned that the Motus MST-Ol is a 1645cc V-Four powered sport-tourer that combines the strong and wide pull ing power of a tradition al twovalve V-Twin with the all-day smoothness of a multi-cyl inder engine.
The engine designand at least its pre liminary manufactur ing-are by Katech, a Tier 1 GM supplier for 30 years. I spoke with Fritz Kayl of that firm about design decisions. He told me that Brian Case and partners wanted an all-American flavor in a V-Four engine. That meant pushrod valve operation and a muscle-car-like "V-Eight look." Because Katech has racing (Corvette!) and production experience with GD! (gasoline direct injection), that was a natural addition to the package. GD! delivers a denser intake charge that boosts torque in a way port injection cannot.
Multiple cams and four valves per cylinder aren't necessary to making stump-pulling torque. All you need is adequate displacement, a high com pression ratio and two valves per cylin der operated by time-proven pushrods and rocker arms, just as in every classic American car V Ei ht
This liquid-cooled engine is mounted longitudinally in the chassis, driving a conventional multi-plate motorcycle clutch and a modern six-speed gear box through bevel rath er than spur primary gears. The engine is narrow—18 inches across. And it looks familiar to any American mechanic because it’s laid out just like a V-Eight. There are right and left rocker covers with a single camshaft in the Vee. The water pump is integrated into the timing-cover casting.
The design choices Motus made tell us this is a sport-tourer, with the emphasis on "sport." It has chain drive, as does just about every sportbike. 0-ring chain is reliable, light and strong. It also has a sportbike's forged aluminum wheels from Marchesini-a 3.5 x 17inch front and 6.0 x 17-inch rear. It has real brakes, too, not decorator sub stitutes that feel like a triple-X grip exerciser.
These are 320mm discs and four-piston monoblock calipers.
Wheelbase gives us another clue: When the emphasis is on "tourer," wheelbase grows to 60 inches or more. While grand for crossing Nebraska, this can make backroad carving difficult. \~ Putting the emphasis on "sport," the Motus' wheelbase is 57.5 inches. A 43mm inverted fork is set at 26 degrees and 4¼ inches trail-sporting but k not extreme.
Four 86.5 x 70.0mm cylinders make 140 , hp at a moderate \. 7800 rpm, with • .~, torque peak ing down at 4500. \Vith 11.5:1 compression that only a liquid-cooled engine can du rably offer, that gives wide, usable torque that's easy to ride for any purpose. The engine's 90-degree design gives primary balance, while a pair of double-speed balancers zeroes out secondary shaking. Lubrication is wet sump with a screw-on filter.
The chassis is triangulated tubular steel, using the engine as a stressed member. A steel rectangular-beam swingarm completes the package. A composite fairing, 35-liter saddlebags and an adjustable-height windscreen provide touring amenities. -
The Motus spec sheet indicates this is a motorcycle for experienced riders who want a specifically Americanand American-made--compromise between sport and tour. Its first engine run is coming up in a couple of weeks. We'll stay tuned. -Kevin Cameron
