Checa was testing his 2012 WSBK bike as well. Kept his tweet ambiguous so as not to give anything away.
V-twin and L-twin are used interchangeably for the ducati engine as I understand it, the L coming in because of the angle being wider than most V-twins and because of the orientation of the engine in the bike, at least the second of which may be changing for the V4/L4 in the gp12, apparently at barrymachine's suggestion
Joined Jun 2007
10K Posts | 1K+
Norah Head
at least the second of which may be changing for the gp12, apparently at barrymachine's suggestion.
And how ungracious, and not very clever, they are too.
Being the initiator of the "better Ducati" you would think they would leak a bit of info or two so I can further analyse how things are going. Good design is evaluation and rectification too!!
On the V or L twins thing.
V is any angle that is not a boxer or L really.
Early V engines often ran 72 deg. cos they were rehashed parts of surplus 5 cylinder radial aero engines ( 360/5 =72 ) with
My memory is probably fading but I believe 90 deg "L" was an old ford? V8 config, Ford where hunting for a smooth V8.
Its not really surprising how much "sticking to what is known" has been done by motorcycle companies. Motorcycle manufacturers have historically been businesses begun in sheds on very low budgets and built up with gradual acquisition of data and knowledge. There early efforts often used known data from auto engines and it is costly to wander too far from such known data, and scary to wander from entrenched design.
And how ungracious, and not very clever, they are too.
Being the initiator of the "better Ducati" you would think they would leak a bit of info or two so I can further analyse how things are going. Good design is evaluation and rectification too!!
On the V or L twins thing.
V is any angle that is not a boxer or L really.
Early V engines often ran 72 deg. cos they were rehashed parts of surplus 5 cylinder radial aero engines ( 360/5 =72 ) with
My memory is probably fading but I believe 90 deg "L" was an old ford? V8 config, Ford where hunting for a smooth V8.
Its not really surprising how much "sticking to what is known" has been done by motorcycle companies. Motorcycle manufacturers have historically been businesses begun in sheds on very low budgets and built up with gradual acquisition of data and knowledge. There early efforts often used known data from auto engines and it is costly to wander too far from such known data,
I generally only post things I actually know, which is not that much on the technical side, so I didn't post after looking it up but I believe technically a V engine can be any angle in excess of 0 degrees and less than 180 degrees, although there have been very few bike engines over 90 degrees. By your theory, which as you know I think is a good one, why do you think the horizontal alignment has not appeared to be problematic with the V2/L2 superbike; different torque and power/power delivery characteristics perhaps for a start?
Joined Jun 2007
10K Posts | 1K+
Norah Head
Yes I guess technically it is, its just some smart arse decided that it was cleverer to call it an L when the angle of the V was exactly 90. I guess it doesn't eliminate the fact it is still a V, its just nomenclature that has adopted.
But anyway my only gripe was that I think the almost horizontally firing cylinders do affect the feel of a bike and in fact it was a pretty big change in speedway bikes. For the reasons previously discussed.
I don't think there's too much to be gained by being to anal about what a V or L is
But anyway my only gripe was that I don't think the almost horizontally firing cylinders do affect the feel of a bike and in fact it was a pretty big change in speedway bikes. For the reasons previously discussed.
I don't think there's too much to be gained by being to anal about what a V or L is
Absolutely, it is purposeless pedantry. I really posted in relation to your first point, which I think is a quite possibly valid theory, to ask you why the horizontal alignment has not seemed to be a problem in theV/L twin in other ducati bikes; my guess is that the 4 cylinder motogp engine is very different in character, and both more powerful and much more peaky for a start.
Joined Feb 2008
2K Posts | 0+
home
Dudes, dudes!
I just did a great experiment. Totally awesome!
You can replicate it:
Draw a horizontal line on a piece of paper.
Now, a vertical line exactly on the left end of the horizontal line.
Very important, that vertical line has to be at an exact 90 degree angle to the horizontal line!!!
Now, if you look closely, you'll see these lines together actually somewhat resemble the letter 'L'. Really, check it out, it's great.
But now....
Tilt the piece of paper by 45 degrees counterclockwise.
And now look closely.
The lines now resemble a the letter 'V'!!!!
Amazing!!!!!
I love the offseason.
I just did a great experiment. Totally awesome!
You can replicate it:
Draw a horizontal line on a piece of paper.
Now, a vertical line exactly on the left end of the horizontal line.
Very important, that vertical line has to be at an exact 90 degree angle to the horizontal line!!!
Now, if you look closely, you'll see these lines together actually somewhat resemble the letter 'L'. Really, check it out, it's great.
But now....
Tilt the piece of paper by 45 degrees counterclockwise.
And now look closely.
The lines now resemble a the letter 'V'!!!!
Amazing!!!!!
I love the offseason.
I think it has more to do with the balance of the bike and the long wheel base than anything else. They just can't get enough weight onto the front end. I'm not familiar with any Ducati street twins but with other twins like the RC51 the engine is in a V position and much closer to the front tire because of the extra clearance of having the engine more upright. I don't think it's a problem on te street goings Ducs because the heads and engines are probably smaller than what is in the gp bike, it wouldn't be a stretch to say the heads on the gp bike have to be larger because of the radical high lift cams and much larger valves. The big compromise to this is that the RC51 has side mounted radiators and it still suffers from overheating with out modification to the cooling system.
RC51
GP? I think this was the 8 or 9 but you can see the engine is already tilted back some what and not a perfect L. You can also see how tilting the engine further back would allow them to move the entire engine towards the front wheel.
RC51
GP? I think this was the 8 or 9 but you can see the engine is already tilted back some what and not a perfect L. You can also see how tilting the engine further back would allow them to move the entire engine towards the front wheel.
Joined Jul 2011
1K Posts | 872+
Dont Know
L is just the way it is positioned in the chassis. You never hear of L car engines because the are always in the V or upright position.
Isn't the theory the L screamer was ok, the new one is called dual pulse, two cylinders fire very close. Who knows what kind of vibration that makes at such high revs, but as you have said its surprising Ducati has not compared the screamer. The one they made for stoner must of been an all out horsepower attempt just for him, but previous versions were more rider friendly. Should be noteworthy Honda and Suzuki were screamers, Ducati strayed from the path.
I have nothing to contribute, but it is the off season.
A square is always a rectangle, but a rectangle is not always a square. An L is always a V, but a V is not always an L. If the V engine is an L, V and L can be used interchangeably. If the V engine is not an L, L and V are not interchangeable.
If I had more time, I would make a sweet Venn Diagram, but I'm a bit short for time. I will leave you with this hilarious gem for your off season entertainment. Notice the location of the RIAA, a subset of the Things That Are Bad, Things That Are Really Really Bad, Industry Lobbyists, and the Intentionally Evil and Ignorant groups. Notice also that French Men 20-36 and People Who Don't Brush Their Teeth are almost a perfect overlap.
http://www.burningdoor.com/..../images/venn diagram.gif
A square is always a rectangle, but a rectangle is not always a square. An L is always a V, but a V is not always an L. If the V engine is an L, V and L can be used interchangeably. If the V engine is not an L, L and V are not interchangeable.
If I had more time, I would make a sweet Venn Diagram, but I'm a bit short for time. I will leave you with this hilarious gem for your off season entertainment. Notice the location of the RIAA, a subset of the Things That Are Bad, Things That Are Really Really Bad, Industry Lobbyists, and the Intentionally Evil and Ignorant groups. Notice also that French Men 20-36 and People Who Don't Brush Their Teeth are almost a perfect overlap.
http://www.burningdoor.com/..../images/venn diagram.gif
Joined Jun 2007
10K Posts | 1K+
Norah Head
Not sure we know if its a problem with the twin or not. Only if we saw a series with Stoner versus Rossi in would it become important.
The Ducati twins do have different dynamic feel though, and on thinking about it I was reminded of laydown engined speedway bikes and the new Husabergs. All 3 of these machines share a dynamic that makes them feel "ok" with the back end hanging out. My original point was, Stoner benefits from this, Rossi does not.
By "ok" I mean that they have a very smooth transition from a tracking to a sliding the back to steer round a corner. They do not seem as twitchy.
It may be a real oddity that they just so happened to pick up a rider who is quite aware that loosing rear traction is not the limit to how fast you can go around a corner, Stoner has taken a few corners with the rear end from age six.
Joined Jun 2007
10K Posts | 1K+
Norah Head
Read these to see what I mean:
http://en.wikipedia.org/wiki/Vibrating_structure_gyroscope
http://en.wikipedia.org/wiki/Coriolis_effect
http://en.wikipedia.org/wiki/Vibrating_structure_gyroscope
http://en.wikipedia.org/wiki/Coriolis_effect
Joined Jun 2007
10K Posts | 1K+
Norah Head
Joined Jun 2007
10K Posts | 1K+
Norah Head
Joined Aug 2008
6K Posts | 748+
Thailand
Here ya go Barry! Visual evidence of the change of engine inclination! Link here (in Italian!).
Attachments
Joined Jun 2007
10K Posts | 1K+
Norah Head
Thats one hell of a confusing set of pictures ........ its like they have tilted the oil recovery backwards even more to compensate. Maybe they are even intending to tilt it back more?
Joined Oct 2007
4K Posts | 744+
Tuscany, Italy
Now the final confirmation has come from Preziosi: the Desmosedici engine is still a 90° V, and he also added that the capacity is full: 1000cc. So, here we would have a 1000cc 4 cyl. 90° V engine with 81mm bore that revs up to 18,000 rpm... Hmmm.
Joined Jun 2007
10K Posts | 1K+
Norah Head
