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Yin and Yang:

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.
Dry weight 227kg (500lbs) (est.)

mst01_qoute.jpg


 
It looks promising and I really hope it works. The current state of American motorcycle manufacturing is embarrassing.

 
It looks promising and I really hope it works. The current state of American motorcycle manufacturing is embarrassing.
Agreed.
This from a recent DealerNews interview with a MOTUS exec. is promising (interviewee seems "grounded" in the realities of the market...?):

"At the moment, there are no other sport-touring motorcycles made in America, they are all imported. We feel the Motus will be a motorcycle that can sit in American dealerships of all types, along side many different types of motorcycles, and still offer a unique experience that no other manufacturer is currently offering. We know Americans like buying American bikes, as evident by the market leader Harley-Davidson. We know some of those customers may have explored other types of sportier, performance-oriented riding styles over the years, only to find out their choice was limited almost exclusively to imported brands. There are many different types of motorcycles out there and we love them all. It's not like we are saying our product is so unique that we will have no real competitors. The market is only so big and the customers have to come from somewhere. We believe motorcycles are still recreational vehicles, and people's tastes and interests can change in an instant. Although we haven't identified any real direct competition yet, our motorcycle will more likely compete with the imported premium motorcycle brands than any existing American motorcycle brand."

 
Plus heck, HD killed their major competitor: Buell. Gotta love it when one of the major players "voluntarily" goes out of business.

 
I played hooky for a little while today to ride up and check these bikes out in Denver. They had two of the three prototypes with them, and these are definitely not show bikes. These guys went out riding in the mountains all day yesterday :p

I present to you some fantastically below average cell phone pictures:







They mentioned that they've cleaned up the look of the frame a little in the go-forward designs, but this is what's on the prototypes:



Completely wet, it's about 550-ish lbs, and the handlebars are EXTREMELY adjustable, front and back, up and down, and even the angle of the handlebar to make it comfortable for your wrists. I sat on it, and was very surprised with the seating position. Much more upright than I was expecting, and it had pretty good balance sitting still. They fired it up, and it definitely sounded like a sport bike (had two brother's exhaust on it). Sergeant seat will come on it from the factory, with a nice wide support in the back, but tapered down toward the front to allow easy foot to ground reach. Even on the "tall" seat (just consists of more foam in the seat), I was EASILY able to flat foot (for reference, I'm on my toes on the FJR + Russell...I could almost flat foot with a Corbin).

Finally, I'm not anything close to being an expert to dispute it, but they said no valve checks. Something about hydraulic lifters. Maybe one of you (wicked) smart guys can explain it.

Of course, still no price, and I still wonder about the chain drive on a "sport tourer."

 
Looks like more of a sport bike and less of a sport tourer. But it's a step in the right direction, at least it's water cooled (at least according to their site it is)

 
I've got to say that gaining the occasional chain and sprocket changes for loosing valve checks is not a bad trad-off IMHO. At least the chain related stuff is right out in the open and easily accessible.

I do like everything else I can see about the bike, except perhaps the price tag (once it's known for sure). I am still very much intrigued and wouldn't mind test riding one to see how it stacks up to a JFR in feel & comfort.

It's a great step forward in my book, period!

 
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I'll post this now since it's written but will have to come back later and make it easier to read and understand. For some reason writing clearly has been tough today. Guess I'm down a quart or two of the intoxicating stuff.

Finally, I'm not anything close to being an expert to dispute it, but they said no valve checks. Something about hydraulic lifters. Maybe one of you (wicked) smart guys can explain it...I still wonder about the chain drive on a "sport tourer."
Old school push rod engines use hydraulically pumped lifters between the push rod and rocker arm to actuate the valves. Lifters tend to work best on engines that turn lower RPMs (<6,500). There are tricks to get them to work at higher RPMs but lifter noise gets created. Also, the rocker arms that are actuated by the lifter need special tricks to get them to work well in hot-rod applications.

At its simplest, a 'lifter' has a body and a plunger on the idea of a can with a ever so smaller can inserted in it so the bottoms face out. Inside the the body is a spring and check ball that regulate how much hydraulic pressure pushes the body and plunger apart. This pressure always takes up the slack between the cam, push rod and rocker arm making valve adjustment unnecessary until something is worn beyond spec. The Honda Nighthawks had lifters and as such no valve adjustment specification.

It is hard to get a push rod engine with lifters to work in high performance engines and tend toward lower revving, high torque motors. Think of Chevy small block engines, they can make serious power but it takes work to extract it. As opposed to some 600cc sport bikes that use virtually direct cam actuated valves, rev 16,000 RPM and make good horsepower at the expense of low torque and low power at low RPMs.

 
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In addition to the above: single-cam Vee engines using pushrods and rockers and hydraulic lifters are becomming outdated for many reasons.

  •  
  • Rubbing friction between the hyd. lifters and the cam lobes becomes more difficult to allay with modern lubricants that lack cat/con-killing metallic anti-wear additives. This problem can be dealt with (to some extent) by using roller tappets.
  • The mass of valve gear: long pushrods and rocker arms tends to restrict RPM (as stated above) but, also tends to require stronger valve springs to control valve events. Stronger valve springs add to the problem of less anti-wear additives as well as (slightly) robbing horsepower.
More modern designs have valve operating mechanisms (camshafts and associated hardware, if any) located close to the valves they operate with minimal (or no) extra pieces. Also, roller tappet devices are in evidence when there are any devices (rockers, etc.) other than just the camshaft's lobes.

Rollers for their anti-friction benefits as well as the, mentioned, new oil's (lesser) formulations.

Suffice to say that the Single Cam located in the engine's 'V' with pushrods and rocker arms is definitely "Old School" -- and on-its-way-out.

The success of the Hyd. Lifter design has been two-fold: quiet and not needing frequent adjustment. Both issues don't apply (much) to newer engine designs.

 
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Late news:

MotorcycleDaily: motus-in-person

...I am fearful of the eventual pricing of this bad boy. It'll likely be Beemer-costly, if not more, particularly using components from Marchesini, Ohlins, Brembo, etc
"Mid-20's"... (Let's just say $23K for the sake of argument.)
Most-likely, ALOT more?

From the article:

“nobody knows what the market is,” and in any case, “we’re not trying to sell tens of thousands of bikes.” The business model is much smaller, around 200 units a year."

Just the cost of production divided-by 200 units = very expensive motorcycle...!

Also from the article:

"Conn told me that every component was evaluated to see if it did one of three things. If it didn’t either increase performance, increase comfort, or increase range it was redesigned. “Everything else is just a gimmick.”

"...minimalistic nature of the bikes. Not much instrumentation, and there’s no ABS."

No ABS...! I doubt they'll sell ANY in America (well, maybe 200...?). :unsure:

 
Old school push rod engines ...
...single-cam Vee engines using pushrods and rockers and hydraulic lifters are becoming outdated for many reasons....
I think the demise of of the pushrod engine has been greatly exaggerated! Has no one seen the ZR1 Corvette with the LS9 (pushrod) engine?

- 6.2 L, 600+ HP

- 0-60 in 3.4 sec.

Sure, pushrods probably aren't the best application in a bike, but the design ain't dead yet!

 
I think the demise of of the pushrod engine has been greatly exaggerated! ...Corvette with ...(pushrod) engine?

...the design ain't dead yet!
Well..., maybe 'one foot in the grave' ? :unsure:

From the intraweb:

DetroitBureau.com website states the following:

"General Motors is planning some major changes for the next-generation Chevrolet Corvette – starting with a high-revving, small-displacement powertrain, that will substitute for the big V8s traditionally found under the hood of the Chevy 2-seater."

Citing highly placed GM executives, the Bureau claims:

"GM has approved the use of a very European-style V8 that will be only slightly larger than 3 liters in displacement. The engine will be of an overhead-cam, rather than traditional overhead-valve (pushrod) design"

 
I think the demise of of the pushrod engine has been greatly exaggerated! Has no one seen the ZR1 Corvette with the LS9 (pushrod) engine?

- 6.2 L, 600+ HP

- 0-60 in 3.4 sec.

Sure, pushrods probably aren't the best application in a bike, but the design ain't dead yet!
There are really only three ways to make more horsepower: You can increase the engine's torque, increase the RPMs, or do both. The overhead valve (pushrod) design limits the rpm range, so to make more power (without using forced induction) they needed to use a bigger displacement engine. The weight of a big lump in the front end of a sports car is a huge handicap in making the car handle well. In a motorcycle that challenge is even greater.

The benefits of a smaller size, lighter weight, higher revving engine are many and far reaching. And there is really no down-side.

 
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At what RPM does the LS9 make 600 (peak) ponies?

They are making a little less than 100 HP per liter. What does the overhead cam BMW S RR make? Is it 180 HP per liter? At what RPM does the BMW make peak horsepower? Why can it turn this many RPMs? The answers are: push rods are old school and limit performance. Harleys use push rods.

That said, there is good argument for mid-range power (torque) and that is where a good engineer will make good design choices (compromises) given the objectives of a particular platform..

 
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