Italian HP????

[gumby302ho]

 So this ducati diavel, it says its an L twin, this L twin makes 162 horse power, how the hell can it make that much power with two cylinders, thats 80 plus per cylinder. I know it must have some fairly big jugs but it just seems outside the realm of a max single cylinder output normally aspirated, what am I missing hear? Never cared for ducati but also never rode one, I had poor friends like me!

[giantkiller]

When I was showing my chopper that I built. Doc from doc's hd  had a "detuned" top fuel twin in his chopper said it was "probably about 450, 480 hp." Biggest juggs uh, cylinders you'll ever see on a motorcycle. Engine almost looked comical. It was so big. He rode it in. (From the trailer)

[ribbert]

So this ducati diavel, it says its an L twin, this L twin makes 162 horse power, how the hell can it make that much power with two cylinders, thats 80 plus per cylinder. I know it must have some fairly big jugs but it just seems outside the realm of a max single cylinder output normally aspirated, what am I missing hear? Never cared for ducati but also never rode one, I had poor friends like me!

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO

[4everFJ]

The KTM 690 Duke single cylinder bike, is close to 80 HP.

[Charlie-brm]

When I was showing my chopper that I built. Doc from doc's hd  had a "detuned" top fuel twin in his chopper said it was "probably about 450, 480 hp." Biggest juggs uh, cylinders you'll ever see on a motorcycle. Engine almost looked comical. It was so big. He rode it in. (From the trailer)

Maybe you're the guy to ask; the H-D's (or at least they call them H-D's) I see on videos drag racing on a track - what's the same and what's totally different about the engines they use from a street issue stock Harley?
Is it about the same as comparing a funny car with a bow tie on the hood to my mom's Chevy Cobalt?

[fj johnnie]

 The "Harley" drag bikes have an 800cc displacement advantage, there is NOTHING on those motors that Harley Davidson is even remotely connected to, other than the big cheques they write. Always makes me laugh when I hear guys talk about how great they are at drag racing. If you are given a huge advantage by the sanctioning body you win.
Kind of  like when Buell, " Harley Davidson" used a 1,000cc twin to beat the Japanese 600's. Wow what an accomplishment. I would embarrassed to even show up.

[Burns]

So this ducati diavel, it says its an L twin, this L twin makes 162 horse power, how the hell can it make that much power with two cylinders, thats 80 plus per cylinder. I know it must have some fairly big jugs but it just seems outside the realm of a max single cylinder output normally aspirated, what am I missing hear? Never cared for ducati but also never rode one, I had poor friends like me!

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO

I suspect a smaller cylinder gets a better power:displacement ratio than a larger one. Seems to me that the intake side of the equation favors several small containers over a single large one and there is probably better flow through more valve area.  Also, the lower mass of the smaller pistons translates into lower inertial load which allows a higher redline, an issue which is also subject to a more inches = longer stroke = higher piston speed at any given RPM string equation.  I wonder what the model airplane motors power:displacement ratio's are. On the question at hand, I doubt that there is an upper limit on the power one jug can produce. Harley dragsters have been making a lot of power for a long time and I wonder what the big naval motors put out.

just my thoughts on the matter.

[giantkiller]

When I was showing my chopper that I built. Doc from doc's hd  had a "detuned" top fuel twin in his chopper said it was "probably about 450, 480 hp." Biggest juggs uh, cylinders you'll ever see on a motorcycle. Engine almost looked comical. It was so big. He rode it in. (From the trailer)

Maybe you're the guy to ask; the H-D's (or at least they call them H-D's) I see on videos drag racing on a track - what's the same and what's totally different about the engines they use from a street issue stock Harley?
Is it about the same as comparing a funny car with a bow tie on the hood to my mom's Chevy Cobalt?

It's pretty much the same as a funny car and your mom's Cobalt.

I'm not a Harley guy either. There is nothing on my chopper that is Harley. The engine is an evolution design. But it's 100% after market(only 120hp. but 120ftlbs! 6 more than my 1350) . And 100 made In the USA . As is the rest of my chopper. Alot hand made in my garage. The only thing that might not be is the ignition.

Picture of my chopper and me. When I was in shape.

Bottom picture is of the mini chopper I made for my daughter.

[gumby302ho]

So this ducati diavel, it says its an L twin, this L twin makes 162 horse power, how the hell can it make that much power with two cylinders, thats 80 plus per cylinder. I know it must have some fairly big jugs but it just seems outside the realm of a max single cylinder output normally aspirated, what am I missing hear? Never cared for ducati but also never rode one, I had poor friends like me!

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO
I cant agree with you on that Noel, alot of big Hardly's out there with same displacement as the FJ and the ducati(not even close) multiple valves dont count either broadly speaking! I know its apples and oranges but 80 hp in one flipping cylinder, I need to read up and see how this L twin can flow so much air.

[Firehawk068]

So this ducati diavel, it says its an L twin, this L twin makes 162 horse power, how the hell can it make that much power with two cylinders, thats 80 plus per cylinder. I know it must have some fairly big jugs but it just seems outside the realm of a max single cylinder output normally aspirated, what am I missing hear? Never cared for ducati but also never rode one, I had poor friends like me!

It's 162 horsepower, and 96 ft/lbs of torque!
At roughly 600cc per cylinder, they are twice the size of our FJ cylinders.
Air flow into and out of the cylinder is the key to these power figures.
They use 4 valves per cylinder, two plugs per cylinder, and huge elliptical throttle bodies.
I believe they use two injectors per cylinder also.
It has 106mm bore, and 68mm stroke, and 12.5:1 compression ratio.

I have ridden one, and I can say that it has BRUTE power! Instant torque and throttle response in any gear, at any rpm. Handles surprisingly well for such a long-wheelbase muscle-bike also, but it is lighter than our FJs.
Would I buy one? No, it's not really my kind of bike.
They do know how to make power though.

[Firehawk068]

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO
I cant agree with you on that Noel, alot of big Hardly's out there with same displacement as the FJ and the ducati(not even close) multiple valves dont count either broadly speaking! I know its apples and oranges but 80 hp in one flipping cylinder, I need to read up and see how this L twin can flow so much air.

Noel is mostly correct on this.

Back in the late 60's/early 70's, Formula 1 car engines were limited to 3.0 liters capacity.
The many manufacturers came up with wildly different designs.
Cosworth(Ford) had their popular DFV V-8 engines. Honda, Ferrari, Gurney, and Matra had their V-12 engines. And BRM even had an "H-16" engine! (Basically two flat-8 engines stacked on top of each other, sharing a common crankcase). They all produced right around 400 horsepower.

One of the problems with multi-cylinder engines, is the more cylinders you have = the more internal friction you have, as there is more ring surface area contact for any given displacement.  However, the less cylinders you have, the beefier those parts are required to be, and you now have to accelerate/decelerate those more massive parts. (Like having a piston and connecting rod that's designed to handle 100 horsepower, instead or 4 smaller/lighter ones that are designed to handle 25 horsepower each)
I think there is some sort of balance between the two, such that some manufacturers choose to design one way or the other. Like Ducati or Yamaha, 2-cylinders or 4? They do make similar power, but make it in slightly different ways.

[gumby302ho]

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO
I cant agree with you on that Noel, alot of big Hardly's out there with same displacement as the FJ and the ducati(not even close) multiple valves dont count either broadly speaking! I know its apples and oranges but 80 hp in one flipping cylinder, I need to read up and see how this L twin can flow so much air.

Noel is mostly correct on this.

Back in the late 60's/early 70's, Formula 1 car engines were limited to 3.0 liters capacity.
The many manufacturers came up with wildly different designs.
Cosworth(Ford) had their popular DFV V-8 engines. Honda, Ferrari, Gurney, and Matra had their V-12 engines. And BRM even had an "H-16" engine! (Basically two flat-8 engines stacked on top of each other, sharing a common crankcase). They all produced right around 400 horsepower.

One of the problems with multi-cylinder engines, is the more cylinders you have = the more internal friction you have, as there is more ring surface area contact for any given displacement.  However, the less cylinders you have, the beefier those parts are required to be, and you now have to accelerate/decelerate those more massive parts. (Like having a piston and connecting rod that's designed to handle 100 horsepower, instead or 4 smaller/lighter ones that are designed to handle 25 horsepower each)
I think there is some sort of balance between the two, such that some manufacturers choose to design one way or the other. Like Ducati or Yamaha, 2-cylinders or 4? They do make similar power, but make it in slightly different ways.

It's about displacement, not the number of cylinders.
Broadly speaking, 1200cc spread over 2, 3, 4, 5, 6, 7 or 8 cylinders is going to produce similar power (but deliver it differently)

IMO
I cant agree with you on that Noel, alot of big Hardly's out there with same displacement as the FJ and the ducati(not even close) multiple valves dont count either broadly speaking! I know its apples and oranges but 80 hp in one flipping cylinder, I need to read up and see how this L twin can flow so much air.

Noel is mostly correct on this.

Back in the late 60's/early 70's, Formula 1 car engines were limited to 3.0 liters capacity.
The many manufacturers came up with wildly different designs.
Cosworth(Ford) had their popular DFV V-8 engines. Honda, Ferrari, Gurney, and Matra had their V-12 engines. And BRM even had an "H-16" engine! (Basically two flat-8 engines stacked on top of each other, sharing a common crankcase). They all produced right around 400 horsepower.

One of the problems with multi-cylinder engines, is the more cylinders you have = the more internal friction you have, as there is more ring surface area contact for any given displacement.  However, the less cylinders you have, the beefier those parts are required to be, and you now have to accelerate/decelerate those more massive parts. (Like having a piston and connecting rod that's designed to handle 100 horsepower, instead or 4 smaller/lighter ones that are designed to handle 25 horsepower each)
I think there is some sort of balance between the two, such that some manufacturers choose to design one way or the other. Like Ducati or Yamaha, 2-cylinders or 4? They do make similar power, but make it in slightly different ways.

Well I do agree on design and they can engineer many shapes and sizes and outputs but with a cost to each, I still believe majority rules up to a certain point. Compare a 400 single to a 400 twin to a 400 four cylinder and easily the power output increases throughout, most likely a cost and production issue with quality not needed to be race proven application, military, aviation etc, etc. Better fuel atomization being spread out over multi valves and multi cylinders will always out compete a single cylinder of same displacement.

[Earl Svorks]

  Over the years from high school, through the eighties, I owned a number of Ducatis. All tower shaft
cam drives. Some desmo units some valve spring types. Long before Ducati's return to GP racing, I had little knowledge of them beyond their being built by an odd little Italian maker.A decade or so into a career in motorcycle mechanics and I began to acquire an appreciation of what a remarkable machine
they really were .Eng Dr Taglioni who was still the head design engineer had, with no small success, persued the path of increased specific output by increasing usable , safe, higher RPM limits. His preference for oversquare  engine dimensions proved successful. as it did for Soichiro Honda. His little singles made more power than many other makes of similar displacement.Add to this, the achievement of his adapting the Desmodromic system of valve actuation to many models to further increase the ceiling RPMs.. Making this standard fare on street bikes. When Burliner motors was the sole American importer for Ducati, Joe Berliner asked Dr T. if he would design a big bike to sell to the Police forces in America. Ducati responded with the  4cyl.Apollo. This was not a commercial success . However when the need for a larger twin to augment their smaller single cylinder bikes arose , Dr T took half of his 4 cyl design and
built his first 'L' twin.  This is not a 'V'twin , as the cylinders are set at 90 degrees. The inherent advantage in this design is it's  primary balance. Look at the HD v twin  They are 45 degrees apart but both rods are on one crankpin. This means there is a huge amount of mass reciprocating nearly together. Both pistons reaching maximum velocity at nearly the same time,(very long stroke, very high piston speed)
and then being halted to zero velocity within a mere 45 degrees of each other. Good as a paint shaker. The Ducati with cylinders disposed at 90 degrees both on the same crankpin is able to cancell out the inertia of each piston as one is at max velocity while the other is at zero velocity.That is perfect primary balance. Easier to make more power when the engine is not shaking itself to pieces All of the subsequent Ducati twins  have been built this way . You must drive one of them to really understand just how smooth they are.
      Cheers
  Simon

[gumby302ho]

  Over the years from high school, through the eighties, I owned a number of Ducatis. All tower shaft
cam drives. Some desmo units some valve spring types. Long before Ducati's return to GP racing, I had little knowledge of them beyond their being built by an odd little Italian maker.A decade or so into a career in motorcycle mechanics and I began to acquire an appreciation of what a remarkable machine
they really were .Eng Dr Taglioni who was still the head design engineer had, with no small success, persued the path of increased specific output by increasing usable , safe, higher RPM limits. His preference for oversquare  engine dimensions proved successful. as it did for Soichiro Honda. His little singles made more power than many other makes of similar displacement.Add to this, the achievement of his adapting the Desmodromic system of valve actuation to many models to further increase the ceiling RPMs.. Making this standard fare on street bikes. When Burliner motors was the sole American importer for Ducati, Joe Berliner asked Dr T. if he would design a big bike to sell to the Police forces in America. Ducati responded with the  4cyl.Apollo. This was not a commercial success . However when the need for a larger twin to augment their smaller single cylinder bikes arose , Dr T took half of his 4 cyl design and
built his first 'L' twin.  This is not a 'V'twin , as the cylinders are set at 90 degrees. The inherent advantage in this design is it's  primary balance. Look at the HD v twin  They are 45 degrees apart but both rods are on one crankpin. This means there is a huge amount of mass reciprocating nearly together. Both pistons reaching maximum velocity at nearly the same time,(very long stroke, very high piston speed)
and then being halted to zero velocity within a mere 45 degrees of each other. Good as a paint shaker. The Ducati with cylinders disposed at 90 degrees both on the same crankpin is able to cancell out the inertia of each piston as one is at max velocity while the other is at zero velocity.That is perfect primary balance. Easier to make more power when the engine is not shaking itself to pieces All of the subsequent Ducati twins  have been built this way . You must drive one of them to really understand just how smooth they are.
      Cheers
  Simon
                  Nice'sa, I alike'a what you a wrote'a! 

[Earl Svorks]

     Thank you sir, I graduated at Whatsa Matta U .