Not sure if you have seen this article about a 4 cylinder Duc or not. If it's old news, my apologies.
Four Cylinder Ducati Superbike Ready In 2017 | Motorbike Only
Four Cylinder Ducati Superbike Ready In 2017 | Motorbike Only
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Engines come in many configurations, leaving aside singles, triples and sixes; for 2 cylinder bike engines there are vee twins, parallel twins and opposed twins; 4 cylinder bike engines can be inline, square four and vee four.
The most popular configurations for both are vee twin and inline four, both have pros and cons the main one being that all internal combustion engines are limited in the amount of power they can produce by the number of times a piston can travel up and down per minute (revolutions per minute or rpm), the limiting factors are heat and stress to the moving parts, particularly the con-rods and bearings. The lighter a piston you can fit the less stress it passes on, so for two engines of identical capacity the one with the four (lighter) pistons can move faster and more frequently, turning the engine quicker and making more power than one with two pistons since they would have to displace twice the amount of space per piston. The problem with this is a four cylinder engine makes more heat (almost 70% of an internal combustion engine’s power is lost through heat), because the cylinders have to be grouped it becomes more difficult to cool them and still remain compact enough to fit in a motorcycle frame (which is why there are and have been only a few 6 cylinder bike engines). A twin cylinder engine, therefore, makes less power – because it cannot rev as high as a four but is slightly easier to cool (whether by air or liquid), which is how a Ducati vee (or L) twin is able to remain fairly competitive with an inline 4, (that and a capacity increase).
At a riding level the difference is really felt pulling out of a corner or from a standstill, where a twin is generally superior because of a lower spread of torque.
There are a number of other factors that affect an engine, the duration, size and number of valves, the bore and stroke of a piston etc. etc. which makes it almost impossible to make sweeping generalizations.
The most popular configurations for both are vee twin and inline four, both have pros and cons the main one being that all internal combustion engines are limited in the amount of power they can produce by the number of times a piston can travel up and down per minute (revolutions per minute or rpm), the limiting factors are heat and stress to the moving parts, particularly the con-rods and bearings. The lighter a piston you can fit the less stress it passes on, so for two engines of identical capacity the one with the four (lighter) pistons can move faster and more frequently, turning the engine quicker and making more power than one with two pistons since they would have to displace twice the amount of space per piston. The problem with this is a four cylinder engine makes more heat (almost 70% of an internal combustion engine’s power is lost through heat), because the cylinders have to be grouped it becomes more difficult to cool them and still remain compact enough to fit in a motorcycle frame (which is why there are and have been only a few 6 cylinder bike engines). A twin cylinder engine, therefore, makes less power – because it cannot rev as high as a four but is slightly easier to cool (whether by air or liquid), which is how a Ducati vee (or L) twin is able to remain fairly competitive with an inline 4, (that and a capacity increase).
At a riding level the difference is really felt pulling out of a corner or from a standstill, where a twin is generally superior because of a lower spread of torque.
There are a number of other factors that affect an engine, the duration, size and number of valves, the bore and stroke of a piston etc. etc. which makes it almost impossible to make sweeping generalizations.
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PA,
That was one of the most efficient ways of stating the differences with a I4 vs a V2 motor I have read in a long time. Nicely done. You could have gone on so much more but you touched on the most significant ones. Heat and stoke efficiency. Cheers.
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same article that ducati has dismissed.
Rumor: Is Ducati Working on a Four-Cylinder Superbike? - Asphalt & Rubber
Rumor: Is Ducati Working on a Four-Cylinder Superbike? - Asphalt & Rubber
jarelj
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Or you can take it directly from Claudio Domenicali:
Ducati boss rubbishes rumours of four-cylinder sportsbike | MCN
Ducati boss rubbishes rumours of four-cylinder sportsbike | MCN
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More cylinders are generally considered easier to balance, but a 90 degree V-Twin like a Ducati or Suzuki are also very smooth. 4 cylinders will generally have more horsepower than many 2 cylinders, but horsepower is the result of torque combined with revolutions per minute. So the slow revving cruisers will frequently have enormous torque, but not as much horsepower. 4 cylinders with smaller pistons may not have as much torque, so won't pull out as fast, but rev much higher, and thus produce more horsepower. As a generalization, 2 cylinder bikes generally get better fuel economy than 4 cylinders of similar size, but even this isn't universal.
Also, There are a number of other factors that affect an engine, the duration, size and number of valves, the bore and stroke of a piston etc. etc. which makes it almost impossible to make sweeping generalizations. MY CONCLUSION: On the straight away long interstate highway you would want to have the lighter weight 4 cylinder engine for touring, and on the curving mountainous road where there are no straight aways you would want the 2 cylinder engine because you would constantly accelerating and decelerating and get max torque at low end speeds for going around corners ...
2 cylinder bikes (V-Twins) have a higher rpm power-band. Also since they have opposed cylinders they tend to vibrate more at higher speeds. Since the 4 cylinder engines fire oppositely they tend to be smoother. Horse power is horse power. Twins tend to have more and a MUCH higher red line. Speed is about RPMs and gearing, not what type of engine it is.
Also, There are a number of other factors that affect an engine, the duration, size and number of valves, the bore and stroke of a piston etc. etc. which makes it almost impossible to make sweeping generalizations. MY CONCLUSION: On the straight away long interstate highway you would want to have the lighter weight 4 cylinder engine for touring, and on the curving mountainous road where there are no straight aways you would want the 2 cylinder engine because you would constantly accelerating and decelerating and get max torque at low end speeds for going around corners ...
2 cylinder bikes (V-Twins) have a higher rpm power-band. Also since they have opposed cylinders they tend to vibrate more at higher speeds. Since the 4 cylinder engines fire oppositely they tend to be smoother. Horse power is horse power. Twins tend to have more and a MUCH higher red line. Speed is about RPMs and gearing, not what type of engine it is.
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those rumors of the Panigale being permanently uncompetitive were a bit premature...the Aragon WSBK round put that to bed.
Just need one funky-... Akrapovic dual-exit highmount exhaust
That being said, if Ducati made a 90 degree V-4 that was frameless like the Panigale, I'd buy it in a heartbeat - a street version of the Desmosedici GP10? Hell yeah, the sound alone would make it worth it.
But I wouldn't replace my 1299 twin for one. The soul of a Ducati is an L-twin.
Just need one funky-... Akrapovic dual-exit highmount exhaust
That being said, if Ducati made a 90 degree V-4 that was frameless like the Panigale, I'd buy it in a heartbeat - a street version of the Desmosedici GP10? Hell yeah, the sound alone would make it worth it.
But I wouldn't replace my 1299 twin for one. The soul of a Ducati is an L-twin.
I find PA's comments about a 4 cylinder producing more heat kind of amusing.
Considering that none of the inline 4 liter bikes I owned before my 1199 were ever as hot as my 1199.
So, by this logic, a Ducati V4 would be even HOTTER than the 1199 or 1299 V2.
Wow, that is a scary and potentially painful thought...
Considering that none of the inline 4 liter bikes I owned before my 1199 were ever as hot as my 1199.
So, by this logic, a Ducati V4 would be even HOTTER than the 1199 or 1299 V2.
Wow, that is a scary and potentially painful thought...
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