Boxer/Flat 6 Cylinder Question

[RP#62]

The ECM uses one pulse generator to calculate RPM and the other to calculate crank position.  It then applies that to a lookup table that factors in the timing curve and from all that it determines which coil to fire when.  Its a fairly standard setup for a distributorless ignition system.
-RP

[Chrisj CMA]

The ECM uses one pulse generator to calculate RPM and the other to calculate crank position.  It then applies that to a lookup table that factors in the timing curve and from all that it determines which coil to fire when.  Its a fairly standard setup for a distributorless ignition system.
-RP

very cool.....It always amazes me to learn how something works.......thanks

[Walküre]

he'd crap a live squirrel.

I'd pay to see that!!!!  How do we get a mechanic here from the 50's????

It's still true for the mechanic from the 60's, and even '70's. I'm here to prove it...here's the ol' flathead I'm working on now - but I would be TOTALLY lost with a new motor. And, at my age, I really don't care to learn.

[Bobbo]

I can see that the self described tech savvy contributors on this thread can sure postulate on something they have no ability to defend by the same method, namely accurate description.

Not only are some not actually reading what I have stated but turning my words around to try to use my words to criticize me. Probably since this is a reflex action brought to the surface by the lower echelons of the thinking process........

I guess to start it is necessary to explain that TDC is an acronym for "Top Dead Center" which refers to the position of the piston in the cylinder related to the crankshaft/pin position for that one particular cylinder............Have you got that now, or are you going to want to argue about that?

I'm sure there will be a few that will argue that this is not correct either...................So now if you are all together in unison, please explain to me how and why:

(1) There are only two pulse generators for the three coils on the Valkyrie motor. The ignition being a CD (capacitive discharge) system means the coils need a positive trigger to make a spark. Note that the pulse generators are at a 90 degree angle from each other. There are not three pulse generators.

(2) There are thee coils. One each for two cylinders. (cyl. 1&2) (cyl. 3&4) and (cyl. 5&6)  and that the firing order of the Honda Valkyrie motor is: 1-4-5-2-3-6

Without needing to go into anymore detail for those with a little bit of automotive knowledge: You more knowledgeable ought to be able to explain pretty clearly (what you say is correct) so the others that are less educated in the automotive arts will be able to understand clearly. Not simply conjecture!

Because up to now, all the guesses are wrong!

***

Speaking of accurate descriptions...

Why do you in one sentence say the Valkyrie ignition is Capacitive Discharge (uses a capacitor instead of a coil) and then in the next describe the three COILS?!

You seem to be badgering others about misinformation, when you are the biggest provider of such...   ???  ???

[Ricky-D]

Join the others trying to reinsert that squirrel up your rectum from whence it came!

Honda says the ignition is a capacitive discharge ignition system.

If I am so wrong, then explain the picture on page 242 in the manual. The 2nd from the top
I refer to the download manual that Dag has available on line.  11-17 manual page
And cursing me with juvenile name calling is expected from such a crass ill educated blob of protoplasm.

***

[Chrisj CMA]

If I am so wrong, then explain the picture on page 242 in the manual.

I have a HONDA service manual.  There is no page 242.  You are still wrong  

[Bobbo]

Join the others trying to reinsert that squirrel up your rectum from whence it came!

Honda says the ignition is a capacitive discharge ignition system.

If I am so wrong, then explain the picture on page 242 in the manual. The 2nd from the top

And cursing me with juvenile name calling is expected from such a crass ill educated blob of protoplasm.

***

First, who is this Bozzo you are referring to?!   

I have the official Honda service manual, and it doesn't list pages as simply numbers. It lists them as pages in sections.  Section 17 is for ignition, and the first page clearly shows typical step up coils with the primary connected to +12 volts and the ICM.  There is no capacitor in the diagram.

Maybe you can post a picture of what you are talking about since no one but you knows what you are talking about...

[Ricky-D]

I made a correction to post #44

The page # I mentioned was the number the pdf file had assigned to that particular page.

Nice to know you boys have your manuals to read.

***

[Bobbo]

Join the others trying to reinsert that squirrel up your rectum from whence it came!

Honda says the ignition is a capacitive discharge ignition system.

If I am so wrong, then explain the picture on page 242 in the manual. The 2nd from the top
I refer to the download manual that Dag has available on line
And cursing me with juvenile name calling is expected from such a crass ill educated blob of protoplasm.

***

I have the .pdf file too.  Page 242 of the .pdf says "crankcase assembly".  This has nothing to do with ignition, which it looked like you were referring to.

I guess you are talking about the photo showing the two pistons lower than the rightmost one.  The journal for the rightmost piston is at 0 degrees (straight up), the center piston is at 120 degrees, and the leftmost is at 240 degrees.  Since the left two journals are equidistant (+120 and -120 degrees) from the rightmost journal, it gives the illusion that the leftmost pistons are in unison.  If you were to turn the crank, you would notice one of the leftmost two pistons would move up, and the other would move down.  Simply look at the photos of the crankshaft to see this.

Where is the info on the CDI?

Please use reply instead of modifying your original.

[Chrisj CMA]

I made a correction to post #44

The page # I mentioned was the number the pdf file had assigned to that particular page.

Nice to know you boys have your manuals to read.

***

Maybe you should get one with words in it so you can read it too......seems the pictures are confusing you a bit

[gordonv]

[quote author=Bobbo link=topic=30334.msg278235#msg278235 date=1310333219
Sorry, but the Valkyrie engine does not have a pair of cylinders at 90 degrees, and four cylinders with TDC at the same time.  It has three sets of opposed pistons set at 120 degrees from each other.  Chrisj CMA correctly pointed out the cam timing marks for each set are 120 degrees apart, and only one cylinder is at TDC on compression stroke at a time.
[/quote]

On the surface, I'll disagree. I went to the manual to look over what the piston/crank layout was. Couldn't figure it out, so went online to ebay and found Pinwall with a crank & pistons for sale. The photo clearly shows the outer 2 pistons (1&2, 5&6) at each end fully extended in their stroke, and the center 2 (3&4) at the bottom of the stroke.

I say on the surface, because it is the cam timing now, that says if the piston is at TDC or not. With 4 pistons at the end of their stroke, each has the potential to be at TDC, but only one of four is at TDC.

How does this work? In theroy, 2 revolutions of the crank gives you the 4 strokes of a complete piston. (2 x 360*) / 6 cylinders = 120* to a TDC of a piston. But if 4 of the pistons are off set by 180* of the other 2, how can you get 120* to meet at TDC?

I don't know where I'm going with this, just trying to understand how and why it does it. I'm not trying to shoot anyone down, just trying to have a discussion.

[Bobbo]

Sorry, but the Valkyrie engine does not have a pair of cylinders at 90 degrees, and four cylinders with TDC at the same time.  It has three sets of opposed pistons set at 120 degrees from each other.  Chrisj CMA correctly pointed out the cam timing marks for each set are 120 degrees apart, and only one cylinder is at TDC on compression stroke at a time.

On the surface, I'll disagree. I went to the manual to look over what the piston/crank layout was. Couldn't figure it out, so went online to ebay and found Pinwall with a crank & pistons for sale. The photo clearly shows the outer 2 pistons (1&2, 5&6) at each end fully extended in their stroke, and the center 2 (3&4) at the bottom of the stroke.

I say on the surface, because it is the cam timing now, that says if the piston is at TDC or not. With 4 pistons at the end of their stroke, each has the potential to be at TDC, but only one of four is at TDC.

How does this work? In theroy, 2 revolutions of the crank gives you the 4 strokes of a complete piston. (2 x 360*) / 6 cylinders = 120* to a TDC of a piston. But if 4 of the pistons are off set by 180* of the other 2, how can you get 120* to meet at TDC?

I don't know where I'm going with this, just trying to understand how and why it does it. I'm not trying to shoot anyone down, just trying to have a discussion.

This one?



If you look closely, you will see that the journal for piston #1 is on the bottom, and the journal for piston #5 is on the top.  These pistons will be at the same height twice per revolution, but they are traveling in the opposite direction.  Like I mentioned to Ricky-D this can give the illusion that they move in unison, when in fact they don't.

TDC simply means the the piston is at the top of it's stroke.  The cam has nothing to do with TDC.  There are two TDC positions per cycle, TDC compression, and TDC exhaust.

I think someone may have posted this before, but it represents the Valkyrie crank very closely:

Flat 6 engine	powered by Aeva

[Chrisj CMA]

This is like arguing that if you jump off a tall building gravity will or will not cause you to hit the ground.  The proof is in the procedure for adjusting the valves.  3 sets of timing marks. Two and only two (opposed pairs) of pistons at TDC at each mark.  If two sets of pistons were in unison so 4 were traveling together and the other two were offset 90° but traveling as a seperate pair THEN there would only be two timing marks and you would be adjusting two sets of valves twice at one mark and one set of valves twice at the other mark.  Maybe some of you (like ricky) have never adjusted valves on a Valk.  If you have, then you know...you have to use all three timing marks twice and you only get to adjust ONE cylinder per stop at any given mark.  Proof that no two pairs travel together

[Madmike]

[quote author=Bobbo link=topic=30334.msg278235#msg278235 date=1310333219
Sorry, but the Valkyrie engine does not have a pair of cylinders at 90 degrees, and four cylinders with TDC at the same time.  It has three sets of opposed pistons set at 120 degrees from each other.  Chrisj CMA correctly pointed out the cam timing marks for each set are 120 degrees apart, and only one cylinder is at TDC on compression stroke at a time.

On the surface, I'll disagree. I went to the manual to look over what the piston/crank layout was. Couldn't figure it out, so went online to ebay and found Pinwall with a crank & pistons for sale. The photo clearly shows the outer 2 pistons (1&2, 5&6) at each end fully extended in their stroke, and the center 2 (3&4) at the bottom of the stroke.

I say on the surface, because it is the cam timing now, that says if the piston is at TDC or not. With 4 pistons at the end of their stroke, each has the potential to be at TDC, but only one of four is at TDC.

How does this work? In theroy, 2 revolutions of the crank gives you the 4 strokes of a complete piston. (2 x 360*) / 6 cylinders = 120* to a TDC of a piston. But if 4 of the pistons are off set by 180* of the other 2, how can you get 120* to meet at TDC?

I don't know where I'm going with this, just trying to understand how and why it does it. I'm not trying to shoot anyone down, just trying to have a discussion.
[/quote]

.. it may help to understand the relative piston positions if you draw two circles, one beside the other.  These two circles represent the 720° of crank rotation that is necessary to allow one piston to go through a complete sequence of events (suck, squish, bang, blow).  now start at the top of one cirle and put a mark there - it represents #1 cylinder top dead center, put another mark 120° from that mark, and then another at 240° from the top.  Now go to the second circle and repeat with marks at the top, 120° from the top and 240° from the top.

The marks on the circles represent the relative positions of the piston and where they are in relation to #1 when it is at top dead center.  If you mark the two circles as each having clockwise rotation and split the circles in half from top to bottom it will show you the direction the piston is travelling and the stroke that it is on, those on the left side of the circle are travelling in an upward direction, those on the right side of teh circle are travelling in a downward direction.  #1 is TDC on compression, the plug has fired and as it crosses TDC it will be into the power stroke.  The next in the firing order (#4) is at 120° before TDC on compression, the piston at 240° on teh first circle is moving in a downward direction and is on intake, the next piston is at TDC 360° behind #1, it is cylinder #2 and is at the top of the exhaust stroke going to intake, the piston at 120° from TDC on the second circle is #3, it is travelling upward and is on exhaust, the cylinder at 240° on teh second circle is the last in teh firing order, it is 120° past TDC travelling in a downward direction in the power stoke.

If you overlap the two circles it represents the positions of the crank pins on a 6 cylinder engine in relation to #1 cylinder.  2 cylinders are at TDC on opposite sides of the engine(1 & 2), 2 cylinders are 120° before TDC n opposite side of the engine (3 & 4) and 2 cylinders are 120° after TDC on opposite side of the engine (5 & 6).

If you look at the service manual section that shows the crankshaft and pistons you can see that each rod has it's own throw and that the throws for each set of running mates are 180° apart this mean that the running mates will at TDC on their own cylinder at the same time but 2 strokes apart (TDC compression and TDC exhaust).

The crankshaft determines whether the piston is at TDC in the cylinder.  The camshafts lobe position will determine what stroke they are on dependent on what the valves have been doing.

[gordonv]

I'm one of those who'll need to wait til lI take the engine apart and "see" the crank/pistons, so I can put these words together with the physical parts infront of me, to truly understand what is happening.

The above pic looks a little bigger than what I first saw, and it does look like they a offset a little more than I first thought.

I'm using the words TDC as representing the point at which you would adjust the valve lash. This takes place only once in your 4 strokes of an engine, along the lines that Chrisj is say. And no, I haven't adjusted my valves, so I don't know for sure. But I have done them on other engines, just not a MV engine yet. Yes, TDC would happen every 2 strokes of a pistion, but only once every cycle (4 strokes) is it aligned with the cam for setting the lash.


Now, I kind of forget, what was the original post about, and why was the question asked, just trying to figure out the engine, or trying to figure out if it can be modified?

[Patrick]

I think StretchPhoto is afraid to ask anymore questions after 2 pages of all this stuff.. I think we have come more than full circle.. The 4 cycles/strokes were discussed/explained as was the expense of this engine with its 2 crank pins per throw[ vs 2 connecting rods per crank pin on less expensive designs].. Then we went into ignition systems and reverted back to crank throw degrees and valve timing.. All said, this is a simple,but expensive, engine design.. I'd better stop now..

[Bobbo]

Most of the side tracking was caused by a few posts full of disinformation.  I doubt that would cause anyone to mess up their bike, but it's better to know how it actually works.  This is the tech board, and sometimes it goes into depth!

[Patrick]

This is supposed to be a tech board and most of the time it's a darn good one, but, misinformation happens.. Flagrant misinformation happens at times, which is a shame because not everyone can filter that out.. That said, this can be a hard/tough type of forum to communicate through..
I guess everyone is about done with this thread including the ignition problems.. I haven't found any resistance specs for these coils and it should be somewhere.. That info [ if it is of a low value] and the fact that the coil primary wants battery voltage [key on] and 100+ volts while cranking pretty well indicates which style system is used..

[Chrisj CMA]

Ya it was a tad painful, but lots of good info came out.  Maybe Ricky-D will be a little more careful from now on before he trashes people..........he is very quiet right now licking his wounded pride probably.  We will all be wrong sometimes, its just some deal with it better than others.......this was not a very pretty one

[Patrick]

Thats true enough, it wasn't pretty at times.. But I think its all figured out now..

I've always thought that turn about was fair play and there have been some nasty characters here at times.. Going back after them with the same treatment is fair..

[98valk]

This is supposed to be a tech board and most of the time it's a darn good one, but, misinformation happens.. Flagrant misinformation happens at times, which is a shame because not everyone can filter that out.. That said, this can be a hard/tough type of forum to communicate through..
I guess everyone is about done with this thread including the ignition problems.. I haven't found any resistance specs for these coils and it should be somewhere.. That info [ if it is of a low value] and the fact that the coil primary wants battery voltage [key on] and 100+ volts while cranking pretty well indicates which style system is used..

http://www.valkyrieforum.com/bbs/index.php/topic,2318.0.html