Cylinder head development

Discussion in 'Airheads' started by Dewey V, Jan 30, 2014.

  1. supershaft

    supershaft because I can

    Joined:
    Sep 9, 2010
    Oddometer:
    9,116
    Location:
    San Francisco Bay area
    I think the 90%'ers here are once again making a mountain out of a mole hill. Not everyone here is a typical googler. Some of us have actual experience doing just the type of thing that the OP is doing and they asked some good questions and made some good observations and/or corrected what the OP had said. It's a forum! And some of the comments/questions are based in real life, not 'on the idiotnet' experience. Yes, it is rare but I wouldn't be here if it weren't so. All of us can't be glassy eyed and overwhelmed eye candy addicts. Some of us here took that wrapper off a LONG time ago!
    #61
    UnclePete likes this.
  2. RecycledRS

    RecycledRS Along for the ride

    Joined:
    Nov 2, 2008
    Oddometer:
    1,050
    Location:
    Vancouver Island
    If anyone thinks the op was too sensitive perhaps you should read what remains of the previous thread he started in olds cool ( http://advrider.com/forums/showthread.php?p=22564142#post22564142 ).

    Some of the "criticism" he recieved in that thread was in my opinion, brutal and as a result he deleted his entries.

    I am guessing he thought he may try again with a better better response. A few of the more blunt comments along with his previous experience have obviously caused him reconsider the effort as pointless.

    Unfortunately we will never see if the work he was attemping had any validity or learn from its success or failure.
    #62
  3. ME 109

    ME 109 Long timer

    Joined:
    Jun 25, 2009
    Oddometer:
    7,082
    Location:
    Albury Australia
    We might end up buying his heads.
    #63
  4. MotorcycleWriter

    MotorcycleWriter Vis ad locum

    Joined:
    Dec 1, 2012
    Oddometer:
    2,323
    Location:
    Yearning for the West
    I may end up sending him mine.
    #64
  5. Bill Harris

    Bill Harris Confirmed Curmudgeon

    Joined:
    Sep 20, 2008
    Oddometer:
    9,871
    Location:
    backwoods Alabama
    Agreed.

    Sometimes dealing with the Internet Collective Psyche is like:

    --Bill
    #65
  6. Stan_R80/7

    Stan_R80/7 Beastly Gnarly

    Joined:
    May 12, 2012
    Oddometer:
    2,614
    Location:
    VA
    I think this thread is an interesting application of the Tinkerbell Effect: http://en.wikipedia.org/wiki/Tinkerbell_effect

    I must admit, without blind hope the world would be a very dull place. FWIW, I wish the OP much success and hope his redesign of the BMW airhead cylinder heads is successful, can be patented, and makes enough money so he can relax on his newly acquired island inhabited by topless serving girls. Wait, wait, wait... that is me transferring my expectations. Either way, Good luck!
    #66
  7. drhach

    drhach We can't stop here, this is bat country!!

    Joined:
    Nov 21, 2006
    Oddometer:
    3,168
    Location:
    Wadsworth
    I followed his last thread and I was wondering how long it would take for him to bail on this one. Thankfully he sent me a link to his Blog, so I can still watch.

    It's funny how people complain about endless "oil" and "tire" threads but then when someone steps outside of the script and tries to tkae the road less traveled, they get dogpiled. Hell, even if he doesn't get it to work, he'll likely learn something. I guess some people have a problem with that. Oh well, I'm following his blog and it's cool stuff.
    #67
  8. Airhead Wrangler

    Airhead Wrangler Long timer

    Joined:
    Mar 4, 2008
    Oddometer:
    7,159
    Location:
    Back in Seattle, FINALLY

    Care to share it? I'd like to see what happens also.:ear
    #68
  9. Bill Harris

    Bill Harris Confirmed Curmudgeon

    Joined:
    Sep 20, 2008
    Oddometer:
    9,871
    Location:
    backwoods Alabama
    "Me Too"... :ear

    --Bill
    #69
  10. Other Bob

    Other Bob Been here awhile

    Joined:
    Nov 16, 2005
    Oddometer:
    450
    Location:
    Detroit 'burbs
    Dewey had way more supporters and encouragement than detractors here. The very few who differed in any material way did so politely and clearly intending to add what they thought was something constructive to the discussion. Or at least they asked questions (like my own) they thought were relevant to his project.

    Their comments were constructive, but Dewey didn't want a dialog. He wanted to monologue on a soapbox as a means of directing select traffic to his blog. Self-interest was his motive. Later, Dewey ... you're not needed here, please DON'T come back.

    So, since he abandoned this thread, shall we just continue a "head development" discussion here or start a new one? Heads like this Fallert SOHC. I wonder what the combustion chamber looks like -

    [​IMG]

    [​IMG]
    #70
  11. Kai Ju

    Kai Ju Long timer

    Joined:
    Jul 29, 2009
    Oddometer:
    3,296
    Location:
    Long Beach, California
    That engine pictured above was designed by Apfelbeck and built by a BMW motorcycle dealer in Germany.

    Here is a bit of info on Apfelbeck, a prolific designer.

    [​IMG]Mike Kron, from Krautheim, Germany, has correctly identified our Motohistory Quiz picture as that of an experimental single-cam Horex cylinder head designed by Ludwig Apfelbeck. Apfelbeck is one of the great names in engineering history from the German-speaking region of Europe. Born in Knittelfeld, Austria in 1904, his breakthrough design was a patent in 1935 for a radial four-valve head with inlet and exhaust valves positioned opposite each other. This configuration (pictured below) results in the maximum utilization of the combustion chamber [​IMG]since the larger inlet valves, positioned on opposite sides of the head, cannot interfere with each other or make contact upon opening. Furthermore, the location of exhaust valves opposite each other gives better and more even distribution of heat, resulting in less distortion. A third, and perhaps the most important benefit is better swirl or turbulence with the incoming mixture, leading to better volumetric[​IMG] distribution of the charge and thus better combustion. Combined with very short, strait inlet manifolds, this was the ultimate high-flow head.

    In 1939, Rudolf Schleicher of BMW recognized the artistry of Apfelbeck's work, and hired him, though this did not immediately benefit motorcycles. Rather, Apfelbeck (pictured here) was assigned to work with the DVL, the German Development Center for Aviation in the development of military aeronautical engines.
    After the Second World War, Apfelbeck was hired by Horex in 1953 where he worked on a 350cc GP twin-cylinder engine. At the same time, he demonstrated his versatility be creating an improved valve train for the Horex Regina (pictured here), whose long and flexible pushrods limited it to no more than 6,000 rpm. To control c[​IMG]osts, no major redesign of the Regina engine was allowed, so Apfelbeck came up with a surprising and revolutionary idea. Removing the push rods, he ran a shaft up the original pushrod tube, and on the upper end of the shaft he mounted a single-lobe cam, resulting in the head pictured in our quiz. This cam operated offset roller tappets that moved two rocker arms with the help of very short pushrods. This provided a much stiffer valve train at roughly the same cost, which should have allowed the engine to rev higher. Plus, the symmetrical cam was able to achieve calculated overlap between the exhaust and intake valves.

    When limited testing showed no greater power or higher rpm, Horex immediately abandoned the project. This was a premature and unfortunate decision, because it was later learned that the culprit in failure to achieve better performance was not Apfelbeck's design, but rather the use of standard Regina valve springs. Kron explains that the engineering staff at Horex was very jealous of Apfelbeck, and resented an “outsider” improving on their designs. He reports that he was told by a person who worked at Horex that inferior valve sp[​IMG]rings were deliberately installed in the Apfelbeck head so it would fail the test and be put aside.

    Apfelbeck was later employed by Maico in 1955, then went to KTM in 1956 where he designed a new two-stroke engine. In 1957, he returned to BMW and in 1962 was sent to work with BMW's importer in Austria where he[​IMG] developed a liquid-cooled boxer four (pictured above and to the right). While it was similar to Honda's GL1000 that would appear more than a decade later, it was tested in a BMW car, not a motorcycle. Shortly after the boxer four was built, BMW called Apfelbeck back to Germany where he helped with development of a new four-valve car engine. The boxer four project was abandoned, and it is believed that the prototype ended up in private ownership in Italy.





    For those wanting more I strongly suggest you Google Apfelbeck Engine
    #71
  12. ReconnaissanceMan

    ReconnaissanceMan Adventurer

    Joined:
    Sep 19, 2013
    Oddometer:
    68
    Location:
    Desert Southwest USA
    Yes. The desmodromic valve train has been used to great advantage by Ducati as well as Mercedes-Benz race machines. Eliminates valve float at high revs. I always wondered why BMW didn't figure out an adaptation. Here's a great example of an OHC. Just one step away from desmodromic.
    #72
  13. Bill Harris

    Bill Harris Confirmed Curmudgeon

    Joined:
    Sep 20, 2008
    Oddometer:
    9,871
    Location:
    backwoods Alabama
    Now yer talkin'. The first time I saw Herr Fallert on one of his bikes, I thought "Oh great. Some Old Guy on an Oilhead". Then I looked closer and was enthralled.

    --Bill
    #73
  14. drhach

    drhach We can't stop here, this is bat country!!

    Joined:
    Nov 21, 2006
    Oddometer:
    3,168
    Location:
    Wadsworth

    I asked him for the address. I think you will need to do the same. It wouldn't be right for me to give it out. he was pretty adamant in his last thread that he didn't want to advertise it and stipulated that people request it personally if they wanted it. I will respect that.
    #74
  15. supershaft

    supershaft because I can

    Joined:
    Sep 9, 2010
    Oddometer:
    9,116
    Location:
    San Francisco Bay area
    That Fallert head: The rocker arms seem to be riding on the same cam lobe?? The included valve angle is way too wide but . . . .

    Fallert's SOHC? What about BMW's R54RS and its DOHC? Their prewar later race bikes were DOHC also.

    Desmodromic? When Mercedes had their one bad ass true desmo (Ducati's use a spring to actually close the valve that last tiny bit), valve springs were not NEAR as good are they are today. Today, their is really no need for desmo. I would run springs up until the need for pneumatic valves. That's what the serious engines have been running for decades(?) now. I think that Mercedes straight eight is the only competitive as in winning true desmo ever?
    #75
  16. Airhead Wrangler

    Airhead Wrangler Long timer

    Joined:
    Mar 4, 2008
    Oddometer:
    7,159
    Location:
    Back in Seattle, FINALLY
    A lot of Ducati race bikes leave out the helper springs and allow cylinder compression to fully seat the valve the last .002" or so. It's said that they idle rougher without the helper springs, but run fine otherwise.
    #76
  17. supershaft

    supershaft because I can

    Joined:
    Sep 9, 2010
    Oddometer:
    9,116
    Location:
    San Francisco Bay area
    That I didn't know. A good friend of mine raced a 916 for years. He bought it brand new when they FIRST came out and never licensed it. He had real good luck with it. It did break a valve guide once and lunched a mess of stuff. I happened to be at a ARMA National one year way back and watched him win one class and almost win another class for second place at Sears Point. First and only time he had ever been there!
    #77
  18. Crisis management

    Crisis management Latte riders FTW!

    Joined:
    Feb 14, 2007
    Oddometer:
    1,874
    Location:
    New Zealand
    That doesn't look like a desmodromic valve train to me, conventional rockers and valve springs with a single cam actuation only.
    I know absolutely nothing about the Fallert head so if I'm wrong feel free to let me know.
    #78
  19. ReconnaissanceMan

    ReconnaissanceMan Adventurer

    Joined:
    Sep 19, 2013
    Oddometer:
    68
    Location:
    Desert Southwest USA
    No, the Fallert isn't a Desmo. You can see the coiled valve springs. The roller on the rocker is a nice touch.

    The desmodromic design utilizes a cam lobe to open the valves and another lobe to close the valves. The rocker arm has one finger to open and one to close. A small spring helps snap the valve shut. Fun to adjust.
    #79
  20. andrewinuk

    andrewinuk Adventurer

    Joined:
    Aug 14, 2010
    Oddometer:
    27
    Location:
    London, UK
    #80