In the land of the V-twins, a new four-cylinder roar is making itself heard. It comes from the all-American Motus MST
The first American four-cylinder streetbike since the end of WW2 has now reached the marketplace. Since 2008 the start-up Motus company based in Birmingham, Alabama, has been patiently developing the MST and higher-performance MST-R sports tourers. Over that time more than 400 customers had placed deposits, and finally production examples have started receiving their purchases. It’ s a literally unique motorcycle that’ s all American in every way – without being a V-twin.
For there’ s nothing on wheels more typically Yankee than a lazy-revving, large cube V8 motor, as attested by the hundreds of millions of vehicles built by GM, Ford and Chrysler over the past century powered by such engines. Though manufacturers from other continents long ago discarded this simple-is-best mechanical mantra, in favour of smaller-capacity overhead-cam multi-valve motors with a greater appetite for revs, US auto makers have refined the humble ohv pushrod powerplant to the extent that it’ s now capable of delivering serious horsepower very reliably, as the results of any NASCAR race, or indeed the Le Mans 24 Hours, will prove.
Contrary to what some seduced by spec sheets may think, there’ s nothing low rent about using pushrods, or sticking with ohv rather than ohc, so long as you do it right – and Detroit’ s engineers are past masters at this, as the men making the Motus sports tourers (= MST) aim to prove. For the KMV4 1650cc ohv V4 Baby Block motor powering the Motus, with pushrod actuation of the two valves per cylinder, was conceived as one half of a typical Detroit-built V8, duly downsized. It was created in the Motor City by auto engine R&D specialist Katech Inc., employing the best design features of its GT1 Le Mans-winning Chevrolet Corvette LS7.R small-block V8 pushrod motor, elected Global Motorsports Engine of the Year in 2006 and still winning races today. For after Motus Motorcycles owners Lee Conn, 43, and Brian Case, 38, founded their company in 2008, they inked a deal with Katech to develop a motor to power the Motown motorcycle they’ d decided to create to plug the gap in the marketplace they’ d felt existed for an American-built sport tourer.
Having enlisted Katech to develop a pushrod V4 motor, the two partners went looking for someone to help them create the motorcycle to house it. In 2009 they signed up Pratt & Miller, another Detroit-based engineering company which, while serial race winners in Endurance car racing with the Corvette C6RS, and partners with GM in developing the supercharged Cadillac CTS-V, also has a broad high-tech R&D capability covering everything from US Army ground support vehicles, through zero emission electric cars, to Le Mans-winning Corvette racers. Although Brian Case conceived the Motus platform to house the KMV4 motor, with the crank running lengthways in the chassis Honda Pan-Euro/Moto Guzzi/BMW Boxer-style, he’ s relied on Pratt & Miller to translate that into a production package via rigorous development of the chassis design, as well as the six-speed transmission with chain final drive, which P&M designed to bolt on to the Katech-built motor. “We’ d have been selling these bikes four years ago if we’ d bought an off-the-shelf engine and transmission package from Rotax, or a V-twin S&S motor like everyone else,” says Case. “We did look at doing that – but then this whole project would have been an exercise inpackaging, a catalogue bike with a bought-in engine. The Motus project began with designing an engine specifically for this bike, then developing the rest of the motorcycle around that. It’ s what European companies do, designing the bike all at one with the motor, rather than plug in and play, like other small American manufacturers.
”The MST-R features the same essential engine platform as the MST, but with a high-lift cam for more duration, revised engine mapping and a 400rpm higher revlimiter than the MST’ s 8,200 rpm redline, thanks to which it delivers 180/134kW bhp at 7,800 rpm at the crankshaft (165bhp/123kW on the MST) with 171Nm/126lb-ft of torque at 5,000rpm (167Nm/123lb-ft). Prices start at $30,975 for the MST, running to $36,975 for the MST-R, plus tax, with a choice of three different colours for each model, and including a two-year unlimited mileage warranty.
“We wanted a motor that had impressive torque from 20-90 mph for smoothness in covering long distances in relaxed mode,” says Brian Case, who adds that this meaty torque figure was the main reason for choosing chain final drive for the Motus, rather than shaft drive or a belt, as were surely valid choices for a sport tourer. “We considered all three options,” he states. “We arrived at chain because it made the most sense for the Motus package. Weight was an issue with shaft drive – the MST needs to be lighter than anything in its class, with the emphasis on the ‘ sport’ rather than the ‘ tourer’ . Torque was the concern with the belt – we had question marks over its durability over a long period in handling 126ft-lb of torque, which is a pretty extreme amount compared to any other production bike with belt drive. We spoke to a leading US belt manufacturer, and one of their concerns was its ability to handle that given how hard a Motus is likely to be ridden. The other issue with the belt was the pulley – with so much torque you basically have to run a shorter gearing, with much shorter pulleys so that the belt will be able to handle it. That means that with a 17-inch sportbike wheel your rear pulley basically blocks the whole wheel, making it cosmetically challenging as well as awkward to package. And as a new manufacturer of motorcycles, we’ re not going to manufacture our own wheels, so our choice would be narrowed if we went to belt drive. So, chain it is!”
A key innovation on the prototype Motus I first rode four years ago that didn’ t make it to production was direct fuel injection/GDI, now commonplace in cars but only ever employed before on two wheels on the unsuccessful Bimota Vdue 500cc two-stroke motor, whose higher revs and doubly frequent power strokes created fuel mapping problems that were never resolved. But direct injection was nixed on the Motus for reasons of cost and timing, so the production bikes now carry a conventional multi-port fuel injection system with RBW/ride by wire digital throttle, co-developed by Motus with Murphy, a company in Tulsa, Oklahoma providing electronics systems for agricultural and industrial-type vehicles, and to Master Craft boats. The Motus now runs a more conventional closed-loop top spray port injection system, with a single AC Delco injector per cylinder mounted above the quartet of 40mm downdraft throttle bodies made in-house.
This innovative powerplant is housed with a 15º forward inclination in a 4130 chrome-moly tubular-steel trellis-style spaceframe conceived by Brian Case. The fully-adjustable 43mm Öhlins NIX30 upside down fork on both versions is set at a 26º rake with 108mm/4.25in of trail, delivering a 1475mm/58in wheelbase, and after initially designing a single-sided swingarm, Case dropped this in favour of a less costly, conventional chrome-moly tubular steel structure. This is matched on the MST-R to a fully adjustable Öhlins TTX36 shock, while the MST carries a Progressive Suspension monoshock adjustable for rebound damping only, each with a progressive rate rocker-arm link, and an easily accessible remote preload adjuster for the spring – a key feature for convenience in tailoring the suspension for luggage and/or a passenger. The MST-R comes as standard with South African-made BST carbon fibre wheels fitted with twin 320mm front Braking discs gripped by radially-mounted four-piston Brembo M3 Monobloc calipers, and a 220mm rear with twin-piston caliper (the MST has hardly less snazzy OZ Racing forged aluminium wheels, and conventional Brembo two -piece calipers working the same discs). Each version comes shod with Pirelli Angel GT tyres, and it’ s worth noting that the rear one of these measures a meaty 190/70-55, a further statement of the fact that the Motus MST is firmly tailored towards the sporting side of the sport tourer divide.
There’ s a choice of seat heights, with a 32.5in/825mm high default version or a lower 31.5in/800mm extra cost option, which seems harsh if specified at the point of sale. Each is hand-made by Sargent in Jacksonville, Florida using their own proprietary foam that makes them comfortable on the long haul. Moreover, as mileating motorcyclists themselves, Case and Conn haven’ t forgotten that their customers will need extra power for all the equipment they’ re likely to carry over the long rides which the touring side of the Motus equation will engender – plug-in GPS units, heated grips, phone chargers, etc. “We knew we wanted an extensive charging system to be able to power all the electrical add-ons our customers will want to have,” says Case. “So we’ ve incorporated a 720W alternator powering a 60amp charging system, and we’ re confident that with three separate power ports the MST has plenty of capacity for plug-in accessories.
”Over the past four years, while finalising development of the production model, the partners established a 12,000ft² factory in the same downtown Birmingham building that once housed the Barber motorcycle collection before it moved to its present purpose built location. Production of the V4 engine has now been transferred in house to the Alabama factory, thus making Motus a true standalone manufacturer. With Birmingham as the Detroit of the South, hosting three major automotive assembly plants and a dozen component suppliers within a 60-mile radius, there was no shortage of qualified applicants for the 25-strong assembly line workforce Motus needed to recruit. The aim is to build up to producing 1,000 bikes annually within three years, especially once the company begins exporting sometime in 2017, says Lee Conn. All the 18 Motus dealers so far recruited in the USA must offer test rides, by the way –and this’ ll be a policy for when overseas distributors are appointed, too, with most interest at this stage from Australia (where V8 Supercar racing rivals cricket in sporting popularity), Japan and Europe.
The chance to evaluate the production version of the Motus in both MST and uprated MST-R guise came via some late fall [autumn!] riding along the superb biking roads of Alabama’ s hill country, as well as the streets of Birmingham. I spent most of my time on a red base-model MST, fitted with the good-looking twin GIVI panniers included as standard (with an optional 30-litre top box available). These are claimed to each be able to hold a full-face helmet, but are consequently wide enough to prevent lane-splitting in traffic with any confidence. Still, climbing aboard revealed an extremely comfortable riding stance that you can precisely tailor to suit your tastes and stature via the finest multi-adjustable triple-axis handlebar package I’ ve yet encountered on any motorcycle, even a BMW, with a five-inch/125mm adjustment up, down, fore and aft, and you can adjust the wrist angle over a 15º span, too. It’ s made by Maine-based HeliBars, and it’ s perfect.
Also adjustable is the Motus’ windscreen, which has a choice of four positions and can be raised a maximum of 3.0in/75mm from its lowest setting, over a five-degree angle. I used the middle setting, and found myself cocooned in still air travelling at 85mph, with zero buffeting in spite of the seemingly rather narrow spread to the perspex. This doesn’ t impinge on your judgement in lining up the bike for turns, as some more all-encompassing screens will do. And yes, that is indeed a KTM headlight on the bike, in case you thought it looked familiar. Together with the twin spotlights fitted as standard, the Motus light package gave outstanding high-speed illumination on a twilight ride back to Birmingham. Again, it’ s fully up to BMW standards. The mirrors are benchmark kit, too – you can see clearly behind you without moving your shoulders. And the horn has a deep and mellifluous note that sounds like a freight train. Coming thru!!
The Sargent seat is now very comfortable, with the improved padding since the last time I rode the Motus giving good support for your bum – plus it’ s narrow where it matters, where it meets the fuel tank, making it easy for a 5’ 10”/1.80m rider to put both feet flat on the ground at a stop light. The tank is well shaped, so your knees tuck in easily to the flanks, avoiding contact with the cylinder heads thanks to the motor being canted forward 15º. Coupled with the quite low-set footrests and the 32.5in/825mm high seat (there’ s an inch/25mm lower option for shorties), this delivers a relaxed and comfortable riding position with a relatively upright posture. The flip-up footrests’ height is not adjustable, but the toe pegs for the gear and brake levers are. Having said all that, I can’ t see the point of fitting the wide 190/55 rear tyre to the Motus, because you ground out the footrests without coming close to using all the rubber. Much better, I’ d have thought, to fit a 180-section tyre which will also make the steering yet lighter, even if it’ s less of a visual design statement.
The Motus really stands out in appearance with the red rocker covers on the MST-R’ s V4 motor representing engineering eye candy for those in search of a break from convention. But that’ s nothing to what happens when you thumb the starter button, and the Murphy ECU’ s excellent cold start mapping helps the engine instantly catch alight, and settle to a high 1,500 rpm idle. It’ s the entry ticket to a concerto from one of the most absolutely unique engine notes in modern-day motorcycling. Sometimes the lilting burble from the twin exhausts makes the Motus KMV4 engine sound like half-a-Chevvy-V8, other times there’ s a fruitier crack more like twin twins, as in double Ducatis – but first, last and always it’ s totally distinctive, and extremely entertaining when heard from the hot seat.
Quite remarkably, once in motion you don’ t have to combat the sideways sway on the Motus that you usually get with any lengthways crank, like on a BMW Boxer or Guzzi. OK, blip the throttle in neutral, and the Motus will indeed rock from side to side – but only until you select a gear. But then just hold the clutch lever in even sitting at rest, and the swaying stops – and on the move it’ s also completely indecipherable. The torque rotation of the lengthways crank is completely cancelled out by the perpendicular gearbox design – very clever. However, I’ d been expecting that by eliminating the balance shafts which had previously removed any trace of vibration from the V4 engine, Motus would have restored at least a few vibes. Sorry, no – zero, zilch, no vibes of any kind till you start nearing the MST’ s 8,200rpm revlimiter, when you start getting a few gradually increasing tingles through the footrests above 7,000 rpm. So that really isn’ t an issue, since it pays to use the bottom four ratios in the six-speed transmission (fifth and sixth are overdrives, for relaxed high-speed cruising) to live in the KMV4’ s muscular happy zone between 4,000 and 7,000 rpm, surfing the serious waves of torque flowing from the motor in recognition of the half-a-Detroit V8 it really is. Top gear roll-on is very good, making this a relaxing mileater in freeway travel. And compared to the direct-injection prototypes I rode back in 2011, Motus has made a big step forward with the engine mapping. The jerky, brusque pickup from a closed throttle that made riding the bikes in city traffic or twisting series of turns quite unenjoyable then is no more, replaced by a suave, smooth throttle response that shows Murphy’ s men know how to map a motorcycle. Maybe they could help Ducati cure the new Scrambler of its similar ailment?
Equally well fixed is the clutch action on the Motus MST, which was previously very stiff, well worthy of any dry-clutch Ducati, with the same effect of cramping up your left hand in working it repeatedly in traffic. On the MST this has now a light, easy pull – though it was just as stiff as before on the MST-R I also rode, because this was the actual bike fitted with beefed-up clutch springs on which Lee Case set an AMA land speed record of 165.81 mph in the 1650cc P-PP (Production pushrod, with AMA-supplied pump gas) class at the 2014 Bonneville Speed Trials, with Brian Case recording 168.69 mph on an identical MST-R in the 1650cc P-PG class (open choice of pump gas). The two of them and their Motus crew then spelled each other to ride the two completely stock bikes the 1,900 miles back to the Motus factory in Alabama in 30 hours, before breaking out the champagne. Those speeds at Bonneville (beating the previous Buell records by over 20 mph) make the Motus MST-R the fastest production pushrod motorcycle in the world – ever.
Also improved is the gearshift action, no longer a little harsh like before, now lighter while invariably precise, with well-chosen gear ratios thanks to the ultra-torquey nature of the engine delivering the luxury of an ultra-long first gear, then three evenly spaced ones before the overdrive fifth and sixth for long-legged high-speed cruising. The engine’ s only turning over at 3,500rpm at 85mph in top gear, so less than halfway to redline according to the good-looking full colour Murphy TFT/Thin Film Transistor dash now fitted. This is ultra-legible in sunlight, with its main screen displaying a tacho, digital speedo, mileage, twin trips, trip computer, fuel gauge, DTE and gear position, and then there’ s an engine screen featuring such data as throttle position, water temp, oil pressure and the usual warning lights. There’ s also a USB port for a thumb drive so you can upload a newer generation engine map, plus a power port for plug-in accessories like GPS or a phone charger, with an extra two more available as options, and a stock 720W alternator powering a 60amp charging system to operate them. The easy-to-use ultra-legible Motus dash is once again benchmark kit, and I’ d be happy to find it on any bike I was going to ride for the long haul.
It was another pleasant surprise to remind myself how well the Motus handles, with a completely intuitive feel to the steering, which make you realise the chassis geometry has been well chosen, and nicely refined. Again, it’ s more sport than tourer, and the MST and MST-R find their way through a series of turns almost on autopilot, with huge feedback from the front tyre via the well dialled-in Öhlins NIX30 fork. The Pirelli Angel GT rubber gives good mileage with excellent grip, plus they heat up fast. But I was particularly impressed by the Progressive Suspension rear shock on the MST, which while adjustable only for preload and rebound damping compared to the MST-R’ s all-singing more expensive Öhlins TTX36 shock, delivered better damping over rough surfaces and a superior ride quality to the stiffer sprung shock from the Swedish suspension sultans. The variable rate spring helped the Progressive shock live up to its maker’ s name, with better compliance over real world road surfaces. OK, the Öhlins may be better for sport riding – but while the MST-R has an extra top end performance kick, and its flatter Rizoma ‘ bar gives a sportier stance at the helm, I much preferred riding the less costly MST. The R-model is a sportbike that you can fit luggage to, but the MST is a true sports tourer, and a very enjoyable real-world all-rounder of a motorcycle.
The Motus previously had too fierce a braking response at the first touch of the lever from the radial Brembo calipers gripping the 320mm Braking discs, making you reluctant to use them too hard in the wet on a bike that’ s obviously however intended to be ridden in all weather conditions – the Motus isn’ t ‘ just’ a sunny Sunday sportbike. That’ s now fixed on the MST, via the two-piece Brembo calipers now fitted which are still mighty effective without being grabby. The MST-R still carries the Monoblocs in best sportbike mode, and you must therefore be ready for the fierce immediate response they deliver, for ABS is not yet available on the Motus. “We’ re working on it, and plan to have it available soon,” says Lee Conn. It’ s needed – quite apart from being a Euro 4 requirement for when the Motus comes to Europe two years from now, in 2017. The sidestand is now easier to find than before, and a centre stand is included as standard – good thinking.
In fact, that says it all about the Motus package – the bikes aren’ t cheap, but except for ABS they’ re very fully spec’ d, and have very little left off them you would want to have – the list of accessories is very short: a taller screen, lower seat, heated grips, heated seat, 30-litre top box and dual power ports. That’ s it. Everything else is already included, plus the MST and MST-R have a unique engine design, invigorating performance, are extremely comfortable for long journeys, and are well finished judging by the build quality of the well-used pair I was riding. It’ s also encouraging to find that the checklist of things to be improved or rectified that I left them with four years ago after riding the prototypes have all been attended to. Make no mistake about it, the Motus is a very serious and well-conceived attempt to service a segment in the marketplace that’ s been completely ignored until now by American manufacturers. The bikes were obviously developed by people who ride big distances themselves and know what they want – and that’ s something far more sporting than a Harley-Davidson Electra Glide or a Victory Vision. Imagine you won the lottery and had the financial resources to develop your own sport touring motorcycle from the ground up. Would it be so very much different than the Motus MST?
TEST ALAN CATHCART PHOTOGRAPHY PHIL HAWKINS
