Author Topic: Engine Porn  (Read 8744 times)

fcheslop

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Re: Engine Porn
« Reply #15 on: October 22, 2015, 08:47:17 AM »
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.

Offline Mosey

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Re: Engine Porn
« Reply #16 on: October 22, 2015, 02:10:15 PM »
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)

Offline b.lindsey

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Re: Engine Porn
« Reply #17 on: October 22, 2015, 03:26:17 PM »
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

Offline dieselpilot

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Re: Engine Porn
« Reply #18 on: October 22, 2015, 06:08:30 PM »
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

Online Vixen

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Re: Engine Porn
« Reply #19 on: October 22, 2015, 07:38:13 PM »
Here is an animation of how the Ducati Desmodromic valve gear works.

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
It is the journey that matters, not the destination

Offline Allen Smithee

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Re: Engine Porn
« Reply #20 on: October 22, 2015, 11:49:47 PM »
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
Quidquid latine dictum sit altum sonatur

Offline Imagineering

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Re: Engine Porn
« Reply #21 on: October 27, 2015, 08:02:34 AM »
I don't know what Bike this is, but interesting all the same ...

Online Vixen

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Re: Engine Porn
« Reply #22 on: October 27, 2015, 08:29:00 AM »
It's a 1959: MV Agusta 125 desmo. Designed by Ruggero Mazza who came from the race department of Ducati.

Mike
« Last Edit: October 27, 2015, 08:34:15 AM by Vixen »
It is the journey that matters, not the destination

Online sco

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Re: Engine Porn
« Reply #23 on: October 27, 2015, 08:00:37 PM »
Guess the engine;
Ars longa, vita brevis.

Offline dieselpilot

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Re: Engine Porn
« Reply #24 on: October 27, 2015, 09:30:18 PM »
I cheated and found the answer. That's an interesting engine, especially for its' time.

Online Vixen

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Re: Engine Porn
« Reply #25 on: October 27, 2015, 09:46:54 PM »
It belongs to this race car

Mike
It is the journey that matters, not the destination

Online sco

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Re: Engine Porn
« Reply #26 on: October 27, 2015, 10:06:26 PM »
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.
Ars longa, vita brevis.

Offline steamer

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Re: Engine Porn
« Reply #27 on: October 28, 2015, 02:53:40 AM »
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline littlelocos

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Re: Engine Porn
« Reply #28 on: November 15, 2015, 01:34:35 AM »
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.


Offline gary.a.ayres

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Re: Engine Porn
« Reply #29 on: September 08, 2019, 09:26:50 PM »
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  :wine1:

Whoah!   :cartwheel: