Engine Porn

[Admiral_dk]

I just saw this Picture of a Ducati V4 1000 MotoGP engine without it's side cover :


This is a very beautiful gear driven cam system - hope you all enjoy it 

[vascon2196]

Awesome....just amazing.

[paul gough]

Desmo madness, beautiful in its own way but definitely a price to pay for it! Paul Gough.

[mcostello]

I think I hear a small "tick" in the gear train, where do I start?

[Allen Smithee]

"So Boss - I've nearly finished that final gear job you wanted but I need a decision. This last gear tooth - do you want one big one or two little ones?"

AS

[Niels Abildgaard]

Dare I say over-enginering?
A V2 two stroke with fuel injection will be ligther ,smaller,cheaper etc and who cares for pollution from motorbikes ?

[gbritnell]

While I fully understand the need to use gears to transmit power in such a confined space I would think that the combined clearance from gear one to gear four in the cam drives could cause some unneeded clatter, especially with the cam lobes loading and unloading. I also question the use of gears when today the use of toothed belts is so prevalent. Yamaha got away from gear lash by using one gear which was split probably 60/40 or 70/30 and had cushion springs between the two gears to eliminate the problem.
It does look very mechanical though.
gbritnell

[Admiral_dk]

Dare I say over-engineering?
A V2 two stroke with fuel injection will be lighter ,smaller, cheaper etc. and who cares for pollution from motorbikes ?

Honda forced / persuaded the whole series to abandon two-strokes and go from 500 cc. to 1000 cc. in order for the bikes not to be slower - though this particular bike is quite a rocket ship with a top speed around 350-360 Km./h (>320 mph).

The weight gain switching from two-strokes to four, went from <130 Kg. to >163 Kg. - so I agree that they are "porkier", much more expensive and no one cares about the pollution from a non road going racer.

I'm not sure this engine is equipped with a desmodronic valvetrain as the road bikes, but rather pneumatic closed valves.

Cost is almost a non-issue as they are only allowed to bring max 6 engines per rider for the whole season !!!!

Not one engine supplier uses belts and Honda spend north off $500.000.000 on the equipment for two riders in a season (four bikes), so I'm guessing that this is the optimum solution.

[bp]

I see that (at least) Toyota, in their Yaris and Subaru (Impreza) have gone back to timing chains instead of belts, to drive cam shafts.  I'm guessing because of the incredible service cost when having to change a belt.

This Ducati looks gorgeous!!
cheers
Bill

[b.lindsey]

Well despite the merits or lack thereof of having this many gears in a train (as George points out), it certainly fits the title of engine porn of the highest order.  Of course I am only reading the thread for the comments, not for the pictures 

Bill

[Tennessee Whiskey]

Don't worry Bill,  I just heard where they are going to print only the contents we were supposed to be buying it for anyhow  and no pics, well sorta  . This is the "Ferrari Syndrome " . Just build something with more complications than a one off Swiss watch and a super exhaust note and  some Sheik or rock star  or something  will pay more money than the law allows.  It just has to be super trick,  super expensive,  and maybe last for just a little while.  Waste of talent,  yet,  brilliant marketing  ..

Cletus

[Jo]

 

Jo

[Jasonb]

When you starting on the 1/3rd scale one of those Jo? Looks to be plenty of studs around the perifery and I'm sure all those gear cutters on your wall would like a bit of action.

Whats the engine? Is it one of Eric's

J

PS fingers crossed

[Jo]

That's a Bristol. I wouldn't put it past Eric to have owned one at some time but they have all gone now

I would like to do a Bentley radial but then I would also like to do a Gnome rotary the problem is work gets in the way 

Jo

[Allen Smithee]

It looks like a sleeve-valve 2-row radial - I'm guessing a Bristol Hercules.

PDR

[fcheslop]

Just hope the Duke is more reliable than of old reminds me of the acronym  Fix It Again Tony (fiat)
Definitely need to pop a few timing marks on that one.

[Mosey]

Nice engine porn!
Ducati Desmodromic road race bikes were and are reliable on the club and AMA Superbike level. When they were winning World Superbike championships, full of carbon and magnesium, things got a little more intense, read expensive, my guess is $1,000,000.00 per. Just look at the record books to see the multiple world championships. The magnesium water pumps ate themselves pretty quickly from corrosion of the coolant in a mixed metals electrolytic stew, requiring frequent replacement at megacost. On the other hand, my 1963'ish Mach One 250 cc single, bevel drive, ran 5 seasons with a change of  plug, points, and valve adjustment and no mechanical DNF's. The Desmo 750 Supersport and 851 while Club racing did the same with occasional trips to the Fast By Ferracci dyno, but no mechanical wear replacements in 40 races.
Besides, I love gears and chains.
Mosey,  (Lucky Duck Racing Team)

[b.lindsey]

Ageless Engines is developing a sleeve valve engine with a similar gear train. Just the gears would be quite an undertaking!!

http://www.agelessengines.com/sleeve.htm

Bill

[dieselpilot]

The gear train in the Bristol sleeve valves was the first to come to mind when I saw this thread. It's straightforward, just high in number. There was a blurb on a build of a Hercules on MEN years ago. I don't know if it was ever finished.

Greg

[Vixen]

Here is an animation of how the Ducati Desmodromic valve gear works. <a href="https://www.youtube.com/watch?v=ocfIYUc5bpU" target="_blank">http://www.youtube.com/watch?v=ocfIYUc5bpU</a>

The desmo valve gear was designed to overcome valve spring bounce at very high rev. However, today, are are alternative methods available such as pneumatic springs etc.

In the desmo valve gear there are two cams per valve, one opens the valve and the second one closes it. They set the gap between cam and cam follower by shims. The typical gap is 1.5 thou. The road going Ducati Desmo engines are robust and reliable and sometimes go 10,000 miles between valve/ cam gap adjustments.

Mike

[Allen Smithee]

The desmo valve gear was designed to overcome valve spring bounce at very high rev. However, today, are are alternative methods available such as pneumatic springs etc.

That's part of it, but the primary benefit is that it allows much more rapid closing of the valve with lower frictional losses (the fiction of opening the valve against stronger valve springs). The rapid closing makes for more efficient induction/exhaust, and it also retains more of the kinetic energy in the induction gas after the valve has closed. This makes for a greater pressure behind the valve before it opens, which means that the valve can be opened earlier (greater valve overlap) for greater power, and the engine will run stably at lower rpm for a given valve overlap (ie you can run a "hotter" cam without as much low-rev popping and banging). There are similar (but less marked) benefits on the exhaust side, but the main benefits are on the inlet.

AS

[Imagineering]

I don't know what Bike this is, but interesting all the same ...

[Vixen]

It's a 1959: MV Agusta 125 desmo. Designed by Ruggero Mazza who came from the race department of Ducati.

Mike

[sco]

Guess the engine;

[dieselpilot]

I cheated and found the answer. That's an interesting engine, especially for its' time.

[Vixen]

It belongs to this race car

Mike

[sco]

Too easy obviously!

Beautiful engine created without regard for expense that kept it competive for more than 10years.  Sounds as good as it looks too.

Simon.

[steamer]

OK   You'll need a cigarette after this one....

http://www.hotrod.com/how-to/engine/hrdp-1109-supercharged-24-cylinder-engine/

[littlelocos]

Hello folks,
Lee Hodgeson (Ageless Engines) has a set of plans for a 14-cylinder, sleeve valve radial.  A HUGE notebook full 'o plans.
See:  http://www.agelessengines.com/sleeve.htm  and http://www.agelessengines.com/svr-desc.htm

(No vested interest here, just pointing out some very impressive work.)
Enjoy,
Todd.

[gary.a.ayres]

I just saw this Picture of a Ducati V4 1000 MotoGP engine without it's side cover :


This is a very beautiful gear driven cam system - hope you all enjoy it 

Whoah!   

[pgp001]

Guess the engine;

A friend of mine is due to start building a 1/3 scale model of that engine very soon, he has booked some time using my Mikron gear hobbing machine for obvious reasons.

Phil

[gary.a.ayres]

Now that is a WILD piece of engineering!