It was just last October when The Kneeslider gave you your first look at the Nembo 32 inverted 3 cylinder engine and the construction photos later. There was a spirited discussion in the comments about whether the design would even work, whether it would fit into a chassis without running into the ground, and many similar comments, you know, the normal reaction when someone tries something radically different. Well, the Nembo 32 had its first track test session this past weekend at the Franciacorta circuit in Italy and in the words of test rider Samuele Sardi, “it’s so small and lightweight that’s easy like a bicycle.â€
The original comments had quite a lot of discussion about how the driveline couldn’t work due to the inverted arrangement so I included this closeup to give everyone better look.
Road holding and handling was reported as being very good, very quick, especially in the bends and S turns. Adding to the handling is the sound of the 3 cylinder engine, especially at 9000 rpm, which Daniele Sabatini describes as spine chilling.
The engine under test is the 170 horsepower 1814cc version. Daniele Sabatini stressed the 32 is not designed as a pure race bike, it’s a road bike you can enjoy on the track.
The second 1814cc prototype is now being assembled for further tests and refinement and then the 1925cc production bikes will be built on request after releasing the price. The production bikes will look much like the bike you see here, a minimal, spartan appearance, but with even more power and torque.
Buyers will have many choices in the areas of engine mapping, tuning, suspension and brakes though the bike itself will maintain the look of the first prototypes.
Daniele said the project is the result of the hard work of their entire team: Giovanni Mariani, Alessandro Sobacchi, Fabio Falcone, Carlo Vercellone, Marco Fasani, CNC expert Luca Signorelli, test rider Samuele Sardi, and mechanic Sandro Carò.
This is a very small team to bring a radical engine to life and in such a relatively short period of time. It’s amazing what you can do when you simply focus on your goal and go to work. Congratulations guys. Great job!
Video below:
B50 Jim says
The proof is in the pudding, and the test results show this design works. Strange-looking though it its, I notice it has extra-long intake runners, which will add bags of torque. It’s not my cup of taco sauce, but obviously a lot of thought and engineering went into it — looks like it’s mostly an engine with all the other bits bolted on to make a motorcycle; that’s smart design. As for the inverted configuration, there will be detractors just because it looks strange, but there’s no reason an engine can’t work just as well “upside-down” as with the crank at the bottom. And there’s that wonderful 3-cylinder wail that I’ve loved since I first heard a Triumph X75 Trident back in the 70s.
baconpocket says
peak power seems a bit low for the displacement, at least in the liter bike scene. i would love to see the power curves though. maybe it has a powerband the size of the louisiana purchase, with torque for days?
baconpocket says
forgot to mention how much i love it
WillyP says
Peak power isn’t everything, if it really is a street bike with track on the side, then low end power, torque and smooth delivery are more important. Too bad there isn’t a number that could reflect ‘power under the curve’.
Chuck says
Don’t forget that it’s air-cooled. That’s a huge limiting factor in the amount of power you can produce.
Kenny says
What I want to know is if they are still on that 150kg dry weight mark, assuming 170kg wet or there-abouts.
HoughMade says
I like innovation. I like seemingly crazy ideas brought to life. I like the “never say die” attitude.
What I am less sure of is what problem this design solves compared to a more conventional design or what advantage it brings. From what I have read, you have the issue that the crankcase is structural without stressing the cylinders….but I’ve not heard if many issues with stressing the cylinders in a more conventional design. They also point out that the cylinders are “out in the wind”- which, being air cooled, is pretty important. I’ve seen no evidence that the cooling is appreciably better than a more conventional design…if there is, I’d love to see it. The other “advantage” mentioned is the radical look. OK, styling is subjective and a significant thing in the motorcycle world.
What am I missing? Is there some functional, practical engineering advantage I have missed? I’m not saying that “practical” is the be-all, end-all of design, but it seems like a lot of engineering issues to solve without gaining a larger advantage in some area.
Random says
+1.
And if there are advantages in balance, as DnA below suggests, I wonder if it isn’t more efficient to adopt counter-rotating crankshafts or just tilt the cilinder a little foward (a la yamaha’s YZ).
Of course these guys can’t be blamed for trying, and many incredible discoveries were actually made by mistake, but if (after trying) there is no dynamic improvement over current designs, not sure de radical look is enough all the trouble.
hoyt says
Not only is this motor inverted, but the exhaust ports and intake ports are a 180 from a conventional design, so that should help cooling. By comparison to a conventional motor, the above head has nothing around it to capture & retain the heat on the hottest part of the motor (no frame, no radiator, no fairing). In this respect, this motor makes the conventional motors seem odd, not the other way around even for liquid cooled motors.
The intake manifold is super cool and is quite a downdraft setup.
DnA says
Very cool. There have been inverted marine diesels before, designed to get the shaft higher for thrusters (water jets.)
I suppose the purpose of this inverted engine is the bike’s balance in motion, especially cornering. The higher center of gravity should keep weight more evenly distributed in relation to cornering forces (gyro, centrifugal, and linear) – at least in theory. It’s certainly worth testing. Oiling would have to be completely re-engineered, but I’m sure they’ve addressed that early on.
I always like a new take on an old idea.
Mule says
The higher center of gravity should keep weight more evenly distributed? More evenly than keeping the weight low?
DnA says
Oddly enough, yes. A low center of gravity is great for typical street handling, but too much mass toward the direction of the centrifugal force will pull the bike away from the direction of the turn. Getting a little more mass midway up helps with steering recovery. The overall physics of the bike also depends on the weight, height, and position of the rider.
Daniel says
I want one. Yesterday.
Will Silk says
Congrats to the Nembo squad for pulling this off, and in such a short time span! Reminds me a bit of the story of the P-51 Mustang that went from North American Aviation drawing boards to flying prototype in something like 6 months.
As for the look of the bike, I think the Nembo team hit it square on the head. Toss a head light and winkers on this baby and be done with it in terms of street use. Great look, especially of the inverted three. I hope they don’t decide later to put fairings on, because that engine is a real gem.
The chain and swing arm do catch the eye as being a bit long, but not to the point that it detracts from the bike as a whole. Again, these guys did a great job and I’m glad to see this project become reality. Awesome sound from that big triple too, how about some quoted torque numbers for that beast?
While I’m sure production will be very limited from the way it sounds, and outside my current budget, I wish these lads the absolute best and can’t wait to see one of these bikes here in the States.
Light is Good says
Re: Awesome sound from that big triple too, how about some quoted torque numbers for that beast?
Here’s some figures from the press release:
http://thekneeslider.com/archives/2010/10/11/nembo-motociclette-inverted-3-cylinder-super-32-rovescio-motorcycle-engine/
‘The “Super 32 Rovescio†Euro 3 engine can have displacements ranging from 1850 cc to 2100 cc, a power ranging from 160 bhp to 250 bhp, and torque values between 16.5 and 24.5 kgm, without the use of compressors.’
16.5kgm converts to 162Nm or 119ft-lb
24.5kgm converts to 240Nm or 177ft-lb
That’s seriously high for such a light bike, and should give phenomenal straight line acceleration, especially if it develops a significant proportion of max torque all over the rev range.
It may also explain why such a long swing-arm is needed. With the centre of gravity already higher than an average sportsbike, lots of torque and a short-swing arm would lead to lots of unwanted wheelies or even backflips : ) And you wouldn’t be able to spin the back wheel easily : )
scritch says
Kinda looks like a bug. But a cool bug. And as the proud owner of a Triumph Sprint ST I can attest to the wonderful sound that a triple makes.
Skizick says
I thought the high centerline on the crank relative to the centerline of the axles would make S’s more difficult. Shows ya what I know…
Anon says
What’s up with the rear suspension? Is that fat damper some sort of air spring?
Steve says
I’m missing something. Everyone else is trying to lower the center of gravity by getting the crank as close to the ground as possible. Supposed to help the bike twitch through the corners. These guys went in the opposite direction?
baconpocket says
i’m no engineer, but i believe what you want in a motorcycle is centralized mass. a reduction in moment of inertia (http://en.wikipedia.org/wiki/Moment_of_inertia) makes it easier to change direction
Slacker says
But you want that mass closer to the axis of rotation (or in the case of multiples axes, at their intersection) to reduce the moment, not necessarily the center of the object itself. A motorcycle’s axes of rotation do not run through the center of the bike. That’s why other manufacturers are trying to lower the COG as much as possible, because the axis of rotation when the bike is leaning runs along the ground between the two tire contact patches.
Nicolas says
that’s what happens when you take a bunch of bored italians, give them a box of black shirts, designer jeans and gay shoes, they find ways to fabricate a beautiful and exotic motorcycle … awesome
Dr Robert Harms says
Its different (God knows Im into “different”) and it runs BUT…. different for differents sake is different , not better. Inverted motors had a purpose on airplanes and inverted V8’s had a purpose in sprint cars but I stll don’t see “better” in this exercise.
Bob Nedoma says
Good point! You invert the (airplane) engine so you can actually see where you going. Makes sense.
Matt "Hype Mann" Herrmann says
Looks awesome! With the inverted design, it should be easy to flick over into the corners. If/when they look at street production, I hope I can afford one!
Marvin says
I’m with kenny on this one if they can pull off 170Kg wet and 170bhp then there is your functional, practical design advantage right there. I know others have done 1Kg to 1 Hp before but not often. I wonder if not stressing the cylinders means they can be lighter or if the internal stresses set a minimum wall thickness anyway, I suppose less stress usually means less metal.
todd says
If the goal was moving mass to the center then I don’t think they achieved that goal to the best extent possible.
Wouldn’t it have been more effective to use a smaller engine? The crank, for one, would be much lighter and have much less inertia. The stroke would have been shorter allowing the engine to be physically shorter, drawing all that mass even closer together. A smaller engine with the same power (HP) would turn and accelerate faster, assuming you aren’t already at the limits of the rider.
At a relatively low amount of power at street speeds you can start to lift the front wheel of a bike. – Basically, an equal weight bike with a lower center of gravity will be able to accelerate at a greater rate before it starts to lift even if it has less power. Likewise the bike with the lower center of gravity can stop faster too.
It does look and sound cool though.
-todd
Ken says
I’ve always wondered about the argument of lower CG makes a better bike in the twisties. I’ve ridden enduros predominantly over the last 7 years and found they handle like a dream in the corners even though they are jacked up sky high. They might have nothing to offer in the straights, but I can hang with sport bikes in the corners!
HoughMade says
You’re right. A higher CoG helps get the bike over in a turn….which is absolutely necessary for a bike. Inherent “instability”, at least to a point, is a boon to cornering on a bike.
Yeti2bikes says
Hand with a sport bike on an enduro through corners? What kind of drugs are you on?
Nicolas says
Yeti, you’d be surprised, but I support Ken’s bragging here, I can testify that a well-ridden enduro such as a DR/XR650 or KTM will give CBRs and gixxers a ride for their money.
But that’s not the point, this inverted thingy is awesome.
Motard says
no drugs. motards on tight roads with a good rider will win more times than not. Light weight, slim bike with leverage are keys.
YouTube has your proof
WillyP says
I have to agree with that, I used to have an XT550 with semi-knobbies and more than once I got some very suprised looks from sportbike riders after following them through some curvey, rough secondary highways here in NH. On the short straights the large rear sprocket gave me an advantage, too.
QrazyQat says
That’s an incredibly small bike for such a big bike. That’s a huge plus right there.
WestOfBen says
Absolutely beautiful. Need more videos! Triple… MMMMMM.
The CofG really doesn’t look that high. Cornering clearance would be a benefit, you’ve moved the widest point of the engine as high as possible. Long swingarm aids traction. It could be shorter, but I am betting the wheelbase is already shorter than most superbikes. It also looks as though they have the swingarm pivot point in a nice location relative to output sprocket. A step further might be to take this down the same track as BMW, with output and swingarm on the same point.
JR says
SO SO SO cool.
Biased because I have a non-inverted 1980 Yamaha triple. LOVE THE SOUND!
JasonB says
I’m glad these guys have seen this through and made it a reality- I thinks it’s a very interesting and fresh design. I can’t argue for or against the technical aspects, but on a basic, admittedly juvenile, level I wish the rider had done one thing in the garage before leaving for the track. Grab the front brake, rev that huge triple way up, let the clutch out in gear and absolutely light up the rear tire. Imagine the sound!
Scotduke says
Inverted engines have certainly proven their worth in aircraft, so why not in a motorcycle? The power to weight ratio of this bike isn’t that different from a Honda Fireblade, Kawasaki ZX10, Suzuki GSX1000R or Yamaha R1. The torque though I expect makes it very different kind of motorcycle to ride with its big displacement, three cylinder motor. I quite like the looks as it happens. The exhaust system looks complex but I suppose the engineering team had a reason for it. I think with all that torque I’d want twin discs up front, no matter how big the caliper. It’s interesting, though I don’t know if I’ll ever be able to afford one. Keep feeding updates on its status please.
Hooligan says
Only the Italians could make a bike with torture seat like that. Comfort? – that’s for wimps. Real men enjoy hemorrhoids.
matt w says
looks cool, sounds cool- but the video? we get to hear it and look at it for a couple minutes and watch it ride away. great. couldn’t they give us a few passes at speed?! C’mon!! i hope this was just a teaser vid and we’ll actually get to see it reach more than 15mph soon.
Hawk says
Inverted?
Gives a whole new meaning to, “Blowing up”
Ian says
Is it me or does it look like the crankcase comes out right where your knee wants to be?
Ottonero says
more photo on ottonero.blogspot
FREEMAN says
Bike looks great. Need more videos of it running around.
Zipper says
Totally outside of the box.The Italians do everything with style. Be nice to see more original ground up builds like this Very interesting article. ..Z
maarten MJ-Works says
I absolutely love it! looks quite nice and i love the way you can see the entire engine and all the CNC parts! Would love to get a look at one of these for real! I’m going to Monza soon so ho knows I might look it up…
this can go into my collection of special engines and new engine idea’s. The big map I’ve got is almost full and that always gives me the superb feeling that people are still being creative with engines!
if you like radical engines look here!!! : http://www.amt.nl/Techniek/Aandrijving-Motor/Alternatieve-motortechniek/Nieuws.htm
grtz
Maarten Janssens
MJ-Works
joe says
Great to see the guys have the bike up and running.It’s real and not just a computer generated cad drawing with lots of hot air yapping about concepts and pie in the sky marketing. Good job guys,I wish you luck for the future.
johnny ro says
Really cool. Needs a fenda extenda, or two.
Tapsa says
The rear fender and what looks to be the tank but is in fact a cover are one piece and the whole thing lifts as such, you can see this in one of the videos they put on YouTube. I am not sure you can really get much longer with the rear fender and do that. The only solution I see is to put a small fender closed to the wheel or…ride only on sunny days!
1937 Indian Chief says
Ok, it’s cool. Seems to have generated a lot of comments on this site. I ride a ’78 Yamaha 750cc Triple nearly every day, love the sound. This bike looks comfortable for about 30 seconds. If it’s truly a road bike that you can enjoy on the track, let’s see it in street legal garb. Now I wonder how much work it would be to flip the motor over on my Yammy…
JR says
Gotta love the sound! Triples are a strange addiction.
Jon says
Interesting, and I’ll admit triples make a lovely sound. The only worry I have is the catastrophic failure of throwing a rod. On my bike, if she auto-detonates, the rod gets driven down through the crankcase. On that one, it’s coming up at your face. If things go terribly wrong, I’ll have enough of an interesting time getting to a stop without a large hole getting punched up through my fuel tank…
Victor says
hummm… how pessimistic you are, did you wake up after nightmare?
Shawn says
On a motorcycle, the COG position has two considerations, as there are two major axes of rotation. There’s the vertical (with the bike upright) axis of rotation, which determines the direction of travel. The mass should be along this axis to make it turn quicker. So the mass should be towards the center of the bike (front to back), offset a little towards the rear tire reduce the moment of inertia. Then there’s the “lean” axis of rotation, which runs along the pavement between the two contact patches. The higher the COG, the greater the moment of inertial with respect to this axis, and the slower the bike with transition given a set force. To reduce the lean moment of inertia the COG should be as low as possible while still retaining clearance. I have no idea where the COG is on this bike, but heads are heavy, so it need not be very high.
Bob says
Honda played around with vertical CG on their racing bikes. Remember the first NSR500s (after the NS500 triples) had the exhausts above the motor and fuel under the engine, following the same logic you describe. What they discovered is that the bike didn’t change direction quicker with a full tank. If you were a giant and could pick up a motorcycle and spin it in the air, it will rotate about the axis defined by its moments of inertia not the contact patch. Reducing the MOI reduces the force required at the contact patch to tip the bike into a corner. Lowering the CG can increase the MOI depending on how it moves from the axis of inertia. Honda later focused on mass centralization (reducing MOI) to get the bikes to change direction quicker.
Geo says
Sorry…but it reminds me of a humpback whale or an armadillo….
Chanson says
That would be the derivative. So easy to measure, I am really surprised it has never gained in popularity as a way to show power.
Scotduke says
The DB600 series engines in the German Messerschmitt 109 fighter of WWII were pretty reliable, which wasn’t good news for the Allied aicraft up against it. And yes, the DB601 and all the other engines in that series were inverted. The Italians built them under licence and used them successfully in some of their best aircraft, as did the Japanese. Prior to that other aircraft engines, such as the De Havilland Gypsy, had successfully used the inverted configuration. The issue of lubrication was solved then so I can’t see why it wouldn’t work now.
Bear says
Great to see this running.
Definitely different.
I would very much like to ride something like this Could be frightening, could be good. Everything I know about mass centralization makes me wonder about having the largest spinning mass so far away from the centre of the bike, and how just far the COG is on this bike from the centre point of this bike (for reference). I’d like to see the designers plotting of the actual COG of this – We’d all be guessing here.
Pitch, Roll, Yaw – all important on a bike.
It’s a triple, so the engines got my attention, but the whole mounting of it has me very ‘interested.’
A great effort to get the bike going, I wish them well. ‘Doers’, are a rare breed.
Mehul Kamdar says
A very nice effort and I hope they are considering marketing their motorcycles stateside.
karl says
Well, this bike is really awesome. Tons of talent in it…