In addition to the 1,645cc V4 Motus MST-01 “comfortable sportbike,” we can exclusively tell you Birmingham, Alabama-based Motus Motorcycles is also developing a lighter, faster, more performance-oriented version dubbed the Motus MST-R. Running prototypes of both bikes are currently undergoing final assembly and will be ready to begin nationwide road validation testing in January. That’s right, an American-made performance bike with a small block V8-derived pushrod V4 engine will be riding on a road near you starting in the new year.

We first showed you the Motus prototype back in July when the company released video and images of its engine development. The V4 at the heart of the project is a beast, kicking out something in excess of 140bhp and 120lb/ft. Those are likely conservative initial figures. The 1,649cc inline-six in the BMW K1600GT manages 129lb/ft and Motus tells us the MST-R will be even more powerful than the MST-01.

This V4 is a scaled-down, four-cylinder version of the Le Mans-winning Corvette GT1 direct-injection small block V8 and is being built for Motus by Detroit-based Katech Engines on the same production line as the LS7R. Like that ‘Vette engine, it has a 90° V, is made from aluminum and uses nickel-silicon-carbide-coated linerless bores. There’s two pushrod valves per-cylinder. Unlike the LS7R, the KMV4 phases its crankpins at 75°, creating a big-bang-like firing sequence.

The KMV4’s single camshaft is mounted in the valley between the cylinders, actuating the valves through pushrods. This is an incredibly compact, simple and light arrangement, the benefits of which on a motorcycle should be obvious. Giving the engine a distinct visual character all its own are four individual 40mm throttle bodies fed by vertical intake trumpets.

In addition to providing Motus with the unique character of an American muscle car, the transverse V4 arrangement is also shorter and more rigid than an inline-four, allowing a relatively short wheelbase and making it a better candidate to serve as a stressed member in the chassis. The engine weighs only 130lbs and measures 18 inches at its widest point. The six-cylinder in that BMW? 22 inches.

The motorcycle that this monster engine is going into is, according to Motus’s Brian case, “Attempting to redefine what an American motorcycle could be. It’s core design principals are performance, comfort and range.” Don’t think of the MST-01 as a sport tourer, think of it as a sportbike that you can tour on.

“The entire Motus concept is basically a rebuttal or counter-point to everything that stereotypes American motorcycles — overweight, inefficient, gaudy, loud, unsophisticated, etc,” continues Case.

“The image you see here is one of our test mules being outfitted as the [MST-R],” says Case. “It is being built up and prepared for testing throughout the country, through all weather conditions, altitudes, etc. We will personally be riding these bikes all over the country to validate them, but also to demonstrate them for all of the independent dealers  who have contacted us and the new ones we hope to meet along the way. We’d like to hear from any rider-oriented dealer who has an interest in carrying a new line of American performance bikes.”

And what of the MST-R? “The MST-R is still a sport tourer,” confirms Case. “It is still a sportbike, just not in the sense of race replicas. They will be comfortable sportbikes equipped from the factory for touring.” As you can see in this sketch, that means things like luggage incorporated into the bike’s design as well as comfortable ergonomics, good wind protection and practical features like power ports for heated clothing and accessories.

“The difference between the MST-01 and MST-R is in trim and cost. Upgraded brakes, suspension, wheels, engine performance, etc,” says Motus presiden Lee Conn.  “We’ve focused on the actual street riding experience and, specifically, fun, usable power for sport touring. that means high torque over a wide rev range, a sporty wheelbase and suspension, appropriate weather protection for comfort and low fatigue over long distances, all in a 500lbs package. The engine we’ve designed should spice up the relatively mundane sport-touring market with the torquey characteristics of a big v-twin combined with the smoothness of an inline-four and an engineered sound unlike anything on the market.”

“Motus is up against enormous challenges, including an extremely tight budget, general economic malaise, intense competition from many other great brands, demographic trends, etc. What Motus has going for it is access to the highest level of development, engineering, fabrication and testing technology as well as backing by extensive research, passion and ambition,” states Conn. Motus hopes to being production of the MST-01 and MST-R next year.

Specs:

CHASSIS
Chromoly tubular trellis spaceframe; engine as stressed member.

FRONT SUSPENSION
43mm USD, fully-adjustable telescopic forks with 120mm travel.

REAR SUSPENSION
Twin-spar chromoly swingarm, fully-adjustable pushrod monoshock with remote preload adjustment, 120mm travel.

BRAKES
Dual 320mm floating discs with four-piston Brembo Monoblock radial calipers; single 2-piston rear caliper.

WHEELS
17 x 3.5” front; 17 x 6” rear.

BODYWORK
Composite

DIMENSIONS
Overall length: 84”
Wheelbase: 31”
Seat height: 31”
Rake: 26º
Trail: 4.25”
Dry weight: 500lbs (est)
Fuel capacity: 6gal

ENGINE TYPE
1645cc, liquid-cooled, dual OHV, pushrod, chain-driven single cam, hydraulic lifters.

TRANSMISSION
Motus 6-speed sequential, unit construction, wet multiplate clutch.

BORE X STROKE
86.5mm x 70mm

COMPRESSION
11.5:1

VALVES
Intake: 44.5mm
Exhaust: 36.8mm
Stainless steel

ENGINE DIMENSIONS
Length: 24”
Width: 19”
Height: 20”

PERFORMANCE
140bhp+ @ 7,800rpm
120lb/ft+ @4,500rpm
Redline: 8,000rpm

ENGINE MATERIALS
356-TS cast aluminum block and heads; forged steel crank, cam, rods; forged aluminum pistons; linerless Nikasil bore

FIRING ORDER
1-4-3-2

IGNITION SEQUENCE
TDC - 345º - 435º - 630º

CRANKPIN OFFSET
75º

MINIMUM OCTANE
87

Motus

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