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A German enthusiast is building his own desmosedici but this one has 8 cylinders.

Desmosedici is the number sixteen in Italian. It usually refers to the MotoGP racer or the limited edition D16RR road bike, because each cylinder of the V4 contains 4 desmodromic valves. However there is another way to get to Desmosedici and that is with a 2-valve 868cc V-8! Details and pics here
 

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Retired Pipe Polisher C2H6O+
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Well, close but not quite. Sedici is 16 in Italian. Desmo is a type of valve train. But cool bike anyway!
 

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That idea was dead 25 years ago after Ducati did it ! Why repeat failure even for the novelty of it ?
 

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I'm gonna have to call BS on this one. First, there is something fishy about the pictures, it just doesn't look right, especially where the cylinders join the engine cases. Looking at the engine the cases appear to be stock, which begs the question "err, what about the crankshaft"? To build a V-8 You really need to have an engine about the width of an inline 4 cylinder to manage the 8 conrods, provide journals to carry the crankloads to prevent bending etc. Which then call into question the standard frame which seems like it would be too narrow...
 

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That idea was dead 25 years ago after Ducati did it ! Why repeat failure even for the novelty of it ?

Not true,

Ducati built the Apollo which was a 1200cc V4, and from what I remember it was never put into production because they didn't have any tires at the time that could handle the weight and power of the bike.

They never built a V-8
 

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I'm gonna have to call BS on this one. First, there is something fishy about the pictures, it just doesn't look right, especially where the cylinders join the engine cases. Looking at the engine the cases appear to be stock, which begs the question "err, what about the crankshaft"? To build a V-8 You really need to have an engine about the width of an inline 4 cylinder to manage the 8 conrods, provide journals to carry the crankloads to prevent bending etc. Which then call into question the standard frame which seems like it would be too narrow...
I thought it didn't look right either, then I went to the guys web site. The guy built a 125cc Honda monkey 4 cylinder. It also looks like he used the stock cases on it also. There is a you tube link and a couple of videos. There is also a link to a miniature 9 cylinder radial engine. The guy seems to be some kind of miniature machinist. So I'm not sure if it is real or not. I'll wait and see if he builds a desmo V-8, or claims to.
 

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I have been in contact with the website owner and he confirms it is real and should be running by the end of the year. He claims he has a patent pending on the crankshaft design. The 2-valve heads do not contain desmodromic valves but are operated by a single overhead cam with single-cam control for both valves with aluminum roller rocker arms.
 

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I thought it didn't look right either, then I went to the guys web site. The guy built a 125cc Honda monkey 4 cylinder. It also looks like he used the stock cases on it also. There is a you tube link and a couple of videos. There is also a link to a miniature 9 cylinder radial engine. The guy seems to be some kind of miniature machinist. So I'm not sure if it is real or not. I'll wait and see if he builds a desmo V-8, or claims to.
Looking at the monkey it looks like he basically grafted the engine onto the front of the monkey crankcase. The monkey only has a stroke of around 35mm which is less than 1 1/2", so the crankshaft is very small.
Looking at the desmo, the bore is 56mm so there is about 2" for each cylinder so adding a little for material between cylinders and a little material for the cylinder offsets you are probably looking probably about 12" for crankshaft width. I guess that may fit inside the cases. then you would need to add material inside the cases for main journals... I guess it could be done, but i will wait and see what actually materializes.
 

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looks like it will run (very poorly) for about 30 seconds, and then-

















kablamo!!!!!!
 

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There is a search function for stuff like this.............

"Not true." ?????

You are poorly read on Ducati and have obviously never been to the factory where the engine is on display. I can't say if this one came before the GP winning Honda engine of the same configuration but it shows the creativity of Dr. T.

Not true,

Ducati built the Apollo which was a 1200cc V4, and from what I remember it was never put into production because they didn't have any tires at the time that could handle the weight and power of the bike.

They never built a V-8
 

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I have been in contact with the website owner and he confirms it is real and should be running by the end of the year. He claims he has a patent pending on the crankshaft design. The 2-valve heads do not contain desmodromic valves but are operated by a single overhead cam with single-cam control for both valves with aluminum roller rocker arms.
Which makes that what.....a quarter speed cam ??
 

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Shove a 502ci into a frame and there you have it. Seems to me I saw a few of those while in Alabama 5 years ago.
 

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A German enthusiast is building his own desmosedici but this one has 8 cylinders.

Desmosedici is the number sixteen in Italian. It usually refers to the MotoGP racer or the limited edition D16RR road bike, because each cylinder of the V4 contains 4 desmodromic valves. However there is another way to get to Desmosedici and that is with a 2-valve 868cc V-8! Details and pics here
The middle cylinders are going to run hot, and the rear middle ones the hottest. Heat management is going to be a problem with this engine. Ducati didn't go to 4 valves for the air cooled engines because of heat management issues, I think.
 
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