Ducati Monster Forum

http://www.motociclismo.it/Edisport/moto/GalleryR2.nsf/foto-moto/Tecnica-motore-CGM-Ducati-01 (http://www.motociclismo.it/Edisport/moto/GalleryR2.nsf/foto-moto/Tecnica-motore-CGM-Ducati-01)

No Desmo, Bevel Driven How about that?  [popcorn]

Kinda cool looking...

(http://i195.photobucket.com/albums/z234/n2f/02-1.jpg)


It's interesting, definitely.  Were the earlier bevelheads more maintenance or less than the current belt-driven cam arrangement? 

Bevel drive = no more expensive cam drive belts to replace. In this day and age of Harleys being belt driven why can't Ducati make cam drive belts that do not need to be replaced every two years?? Me thinks I smell planned obsolescence... the plot thickens. [roll]

Besides, you can put the cool old see through sight glass pieces on the heads of the bevel drive motors and watch stuff spin around! [clap] [popcorn] [bacon]

Looks like an efficient way to power a SOHC valvetrain to me. It would be great if the engineer could figure how to produce it as cheaply as a Pantah-head. I wonder if they are considering a desmoquattro?

I'm witchoo, man.  < Maintenance =  [thumbsup] &  [clap] .  In their 4-cyl engines, Toyata dropped the timing belt in favor of a (maintenance-free) timing chain.  Y'know, if the belt saves 1 lb over the chain, I'd take the chain and be happy to keep the money spent on maintenance.

George

every 2 years my arse. how about every 15k which is 14-18mos.

O.K., let me just start out by saying I'm NOT pregnant doging (not there's anything wrong with that)  BUT...

Is there a more expensive 4-stroke motorcycle motor to maintain than a Ducati?  Seriously.  Out of all the other motorcycle motors currently being manufactured, is there anything else out there that rivals the cost-per-mile to haul itself down the road compared to a Duc?  I honestly don't know but I suspect that with the exception of maybe  a Bimota, a 4 valve L-Twin Desmo wins that dubious distinction.

So! "new" bevelhead?  Bring it!  This is probably as good a time as any for Ducati to pull an otherwise excellent motor up to more acceptable standards for routine maintenance. 

I have heard the belts are going away... and "gear drive" is coming (bevel?).
But the engine case in the display picture is not what I understand will be the new design...  ;D

-and the intake *as pictured* will simply not work!

Oh, there is something else "new" for the new motor that has not even been mentioned yet  8)

 [popcorn]

Flux Capacitor?

Hyper Drive??

Close, Mr. L'Smart, very close...

"Plain" (shell-insert type) engine bearings.
You know, like the ones in just about every other engine on the planet.
Which would require: A horizontally split crank-case -not a vertical split case like we have now
(the above picture shows no parting line/fasteners to facilitate a horizontal split)
Which, of course, would require a new design high-pressure oil system...
You'd toast bearings very quickly with the oil delivered the current system provides.
(roller main bearings can run with oil delivery "interuptions" -plain bearings start to go up in smoke almost instantly)

Roller bearings are used on the crankshaft mains now. 
Very low rolling friction once set up correctly -a nice benefit.
But: They can withstand only "so much" hammering before failure. 
They are heavy.  They cost (much) more. 
The machine work required to use them is hugely more complicated than plain bearings.
And you have to shim the crank for proper preload precisely to make them work...
That takes time, which equals money.  $$$

We'll save:
Time.  Money.  Weight.
Oh and we'll get better oil delivery too!   [thumbsup]

hey now, I think my cost of ownership's not so bad at all! 

O.K. so ditch the roller bearings and use brass shells - just like the D16GP6.  Makes sense (and 'cents'!) but when you say, "high pressure" oil system, I think of dry sump motors with a remote oil tank (Corvette LS7 for example).

Wassup with that?  Remote oil tank somewhere on the new Ducati or is that too car-y?  [laugh]

I do like the idea of gear driven cams (bevel drive or "traditional" gears, like the RC51) as that ultimately could/should mean less maintenance; it's also the technology used on all the GP machines if I'm not mistaken for the last quarter century.  But if I play devil's advocate on this, I don't see the dealers just rolling over on the less maintenance idea - service has got to be their bread and butter.  My point is, to keep their dealer network viable, would a meaningful reduction in routine service cost be in Ducati's best interest long-term?  Maybe it won't be in cam belt replacement but the cost to play is  bound to be up somewhere.

And if they're re-thinking their approach to engines in light of contemporary technologies, what about traditional valve springs?  Total heresy, I know  [evil]   

Hell, if Ducati wanted to go really berserk, they could add "high-pressure" (pneumatic) valves to the list...

if I'm not mistaken, the old bevel drive heads required more frequent maintenance than the belt drive of today, that may speak more to the state of the technology in those times rather than the actual tech, but just saying

Not to get totally side tracked but I think you're right... In the late 50's I think Porsche had used bevel drive on one of their flat fours in endurance racing.  Ended up there were only two people on the face of the earth who could get the little gem (a-hem!) to run at all.

Ahhhh-HA! now I'm beginning to see the Ducati angle on all this  [evil]  [laugh]

Yes i heard that too about horizontial split cases which will save a lot of money in labor...

Those are coming for some/all of the 2-valve motors.

Oh

My

God


 :o  [laugh]

What for? Ugh

I wouldn't think they would change to springs on the SBK or GP either. I've read the desmo is an advantage that the GP guys are trying to counter with pneumatics.

Would this new mythical engine be based on the Desmocedici engine? I've never seen any design details on that engine. Changing from the Pantah to horizontally split cases is almost a clean sheet design, unless the D16RR layout can be used. Its really pretty wild that the Pantah design has lasted this long, but its still working pretty darn good. Very interesting subject.