Topic: Can't find non-resistor plug caps--how do you run DR8EIX iridium resistor plugs?

[Holden]

Great kmb... thanks for that, I have no problem being corrected ... on that issue, but were back to ignition 'speed' and how many degrees more advance electronic ign. will produce a spark vs. points  with the stock advance unit and at the // max. advance mark ?? It can't be the same.
How does it relate to the actual crankshaft position ( deg. )... or are points as fast as electronic ?

I'm far from being an expert, but my understanding is that when you set the timing using a strobe, advance or otherwise, you are setting the timing based on the spark.  The strobe is triggered by the coil discharge through the spark plug wire.  Therefore, it doesn't matter if you lose "lag" when you go to an electronic ignition...you are setting the ignition to fire the coils based on the actual spark and nothing else.

[kmb69]

Spanner, Let's just say in theory that the points system takes 5deg of crank rotation to fire the coils (I have no idea what it really is). The cam that opens the points would have to open the points at 40deg BTDC for the coil to fire at 35deg. The electronic triggering is not instantaneous but much faster than the Kettering system. Lets say it takes 1deg of crank rotation to fire the electronics system. The electronic trigger would be set to 36deg BTDC for the coil to fire at 35deg. Each system is designed to trigger the cycle depending on the time it takes to fire the coils at 35deg. The timing light sensing from the secondary coil winding is telling you when the spark occurs - not when the trigger initiated the cycle.

[Simpson]

Spanner, please thumb to the ignition section in the shop manual and read it over. Around page 85 it clearly talks about fundamentals. F means fire. Not get ready to fire or light the fuse and run. Advance timing moves to 23.5 - 26.5 degrees not 35 degrees. 

[Pinhead]

Spanner, Let's just say in theory that the points system takes 5deg of crank rotation to fire the coils (I have no idea what it really is). The cam that opens the points would have to open the points at 40deg BTDC for the coil to fire at 35deg. The electronic triggering is not instantaneous but much faster than the Kettering system. Lets say it takes 1deg of crank rotation to fire the electronics system. The electronic trigger would be set to 36deg BTDC for the coil to fire at 35deg. Each system is designed to trigger the cycle depending on the time it takes to fire the coils at 35deg. The timing light sensing from the secondary coil winding is telling you when the spark occurs - not when the trigger initiated the cycle.

THIS.

[Spanner 1]

Now were getting somewhere!... yes the // marks may actually open the points at 40 deg. because  the crank will have turned 5 deg. before the spark actually happens ( with points )... anyone have a problem with that concept? I'll presume no. O.K., with electronic your still timing at the // mark BUT the // mark is set to accommodate the 5 degrees of crank turn before the points can make the spark.
Not so with the electronic....... maybe 1 degree ?, so max. advance is 39deg, not 35deg.
The electronic is not , quote, " set to 36deg. for the coil to fire at 35deg. ".. no such thing , it just follows the advancing point cam exactly as the points do.........
Simpson (above ) further proves my point by stating that 35deg. of physical rotation of the points cam produces 23.5 to 26.5 of actual advance due to the slow switching of the points ( allowed for in design )

[Pinhead]

Now were getting somewhere!... yes the // marks may actually open the points at 40 deg. because  the crank will have turned 5 deg. before the spark actually happens ( with points )... anyone have a problem with that concept? I'll presume no. O.K., with electronic your still timing at the // mark BUT the // mark is set to accommodate the 5 degrees of crank turn before the points can make the spark.
Not so with the electronic....... maybe 1 degree ?, so max. advance is 39deg, not 35deg.

Except for the fact that the strobe flashes when the actual spark occurs, NOT when the primary winding is opened.

Also, voltage in the secondary winding doesn't light the strobe. It's the current flowing through the plug wires that induces current through the strobe. This means the strobe only lights AFTER the spark has been fully initiated (not just voltage ionizing the gap).Which means no matter how the coil is triggered, the spark occurs at exactly the same time (if the light strobes on the same timing mark).

[Spanner 1]

Your ignoring crank rotation again !......... points firing at the // mark provide a spark at , as Simpson kindly reminds me, 23.5 to 26.5 deg. BTDC. With electronic timed at the // mark where has the crank rotated to at the time of spark ?

[Holden]

I don't understand how crank rotation plays into this.  It drives the ignition the same, whether it's points or electronic.

[Spanner 1]

It takes time for an ignition, points or electronic, to make a spark from the time it is triggered to do so, in the meantime the crankshaft continues to rotate, so if a points ignition is triggered at the same 'place' ( timing mark ) as an electronic ignition is , the crank will have turned a lesser amount when the electronic ign. makes the spark. Why ?, because the // advance marks are set for  slower point ignition NOT electronic..........

[scottly]

When the advance marks line up at over 2500 RPM, when checked with a strobe, the timing is correct. Period.

[Pinhead]

Your ignoring crank rotation again !......... points firing at the // mark provide a spark at , as Simpson kindly reminds me, 23.5 to 26.5 deg. BTDC. With electronic timed at the // mark where has the crank rotated to at the time of spark ?

I'm ignoring crank rotation because it has absolutely no effect on the strobe.

UNLESS you're setting your timing on the PRIMARY SIDE, crank rotation has NOTHING to do with the firing of the coil.

THE STROBE IS TRIGGERED BY THE SPARK. YOU ADJUST YOUR TIMING SO THE SPARK OCCURS ON THE TIMING MARK. NOT BY WHEN THE DISCHARGE OF THE PRIMARY IS INITIATED.

You are correct that points take longer to produce a spark. But the time taken is BEFORE the spark. We don't CARE what happens BEFORE the spark occurs since we time for the SPARK, itself, which is what lights up the strobe.

[Retro Rocket]

It takes time for an ignition, points or electronic, to make a spark from the time it is triggered to do so, in the meantime the crankshaft continues to rotate, so if a points ignition is triggered at the same 'place' ( timing mark ) as an electronic ignition is , the crank will have turned a lesser amount when the electronic ign. makes the spark. Why ?, because the // advance marks are set for  slower point ignition NOT electronic..........

Ok, and your point is.?   I am serious, whats your point. The electronic ignition smooths out the ignition and keeps it consistent, so this stock points ignition that you love so much is proven inferior by your own statements...   That "lag" that you keep referring to gets worse as the points age, how can that be "as good".I still don't understand what your point is, the points are old, almost forgotten tech that has been replaced with a better more reliable system that only falters when it breaks, so it is consistently firing at the exact same point for the life of the ignition.
This has to be a better more controlled way to keep your engine running, unless of course you are a purist that just wants to keep it all stock.

[Spanner 1]

Pray tell me then, at how many degrees does an electronic ignition fire a spark when strobed at the //  max. advance mark @ 2,500 rpm ?

[Pinhead]

Pray tell me then, at how many degrees does an electronic ignition fire a spark when strobed at the //  max. advance mark @ 2,500 rpm ?

Since I don't know at what degree the // marks are, I have no idea. But it is completely IRRELEVANT.

[scottly]

Pray tell me then, at how many degrees does an electronic ignition fire a spark when strobed at the //  max. advance mark @ 2,500 rpm ?

The same degrees as a point ignition...

[Spanner 1]

Wrong , my friend it's completely relevant... look, the physical advance of the points cam from 'T' mark is 35 deg....... Why ?, because Honda discovered that it took 35 deg. af physical advance to produce a ( desired ) max. spark advance of 23-26 degrees with point ign.... are you going to argue that ?? This 12 deg. 'lag' is a known quantity and is completly relevant to why the max. advance is 35deg. Now with your electronic timed at the // marks, where is your spark ? Degrees, please.

[Pinhead]

Wrong , my friend it's completely relevant... look, the physical advance of the points cam from 'T' mark is 35 deg....... Why ?, because Honda discovered that it took 35 deg. af physical advance to produce a ( desired ) max. spark advance of 23-26 degrees with point ign.... are you going to argue that ?? This 12 deg. 'lag' is a known quantity and is completly relevant to why the max. advance is 35deg. Now with your electronic timed at the // marks, where is your spark ? Degrees, please.

IF you times your points using a strobe on the plug wires, it will fireat exactly the same point.

You're looking at this backwards.

If you set the electronic ignition to open the coil  primary at the same time as with points, you're correct that the EI will produce more advance. BUT at the same time your strobe would no longer flash on the timing marks.

I think you're misunderstanding how an inductive timing strobe works...

[Spanner 1]

Excuse me but you only have the // marks to go with, not some 'new' electronic advance mark !!!!!
If you strobe your electronic @ the max. advance mark ( what else can you do ?/) your timing advance is already wrong, sorry.
PS... nobody's 'opening ' any primaries (?)...... were strobing the HT to know the exact moment of spark........ thank you

[Retro Rocket]

Excuse me but you only have the // marks to go with, not some 'new' electronic advance mark !!!!!
If you strobe your electronic @ the max. advance mark ( what else can you do ?/) your timing advance is already wrong, sorry.

Well i don't give 2 #$%*s if you answer me or not mate but it can't be wrong if it all runs better than the friggin points.....
Would you like to explain that..!!

[Pinhead]

Let's go through this step-by-step.

1) Points close and charge the coil.
2) 195° later the points open. The spark does not yet fire.
3) Magnetic field in the primary collapses.
4) Voltage is induced in the secondary.
5) Secondary voltage rises until the plug gap is ionized enough to allow current to flow through the gap.
6) At this time, the strobe flashes and if you're lucky, the timing marks are aligned.

2 to 5 takes, say 5 degrees.
Note that the strobe flashes on step 6 at virtually the same time the spark occurs.

Electronic goes through the same steps:

1) Charge
2) Remove primary current source
3) Mag field collapses
4) Secondary voltage is induced
5) Plug gap is ionized until current can flow through the gap.
6) Strobe flashes.

Time from 2 to 5 is, say, 1 degree. But the strobe still flashes an inconsequential amount of time after the spark occurs.

But notice WHEN the strobe flashes: AFTER the spark has been initiated. Whether it be points or electronic, the time between the spark, and flash of the strobe, is effectively zero.

Everything that happens before the spark, and consequential strobe flash, is completely irrelevant to timing your ignition using an inductive timing light.

[Spanner 1]

Lets go thru' this step by step....
1, The points are strobed at the // max. advance mark which produces a spark between 23-26 deg. BTDC.
2. The electronic ign. is strobed at the // max. advance mark which produces a spark between ??-?? deg. before TDC.
 You still haven't answered this question, and don't say 'same as points' again , please anyone 

[Spanner 1]

Gone to bed... think about it, especially the variable between points/electronic!

[Skunk Stripe]

We have thought about it and what, 7 of us, are on exactly the same page. That leaves you.
You keep missing this. If the spark happens when it is supposed to whether it be the F or the // marks, Then it is correct, no matter what ignition you are running. As long as that occurs, it does not matter when the ignition itself triggers as the bike is concerned about firing between the F and // marks. That is ALL it cares about. the bike does not give a darn when the ignition trips. It could trigger 100 degrees off, as long as the coil collapses and spark is produced in the proper range, the bike does not care. This is what we are trying to tell you.
The ONLY thing that matters is when spark occurs, nothing more.


It seems that my last post mysteriously vanished.

[kmb69]

Spanner, please thumb to the ignition section in the shop manual and read it over. Around page 85 it clearly talks about fundamentals. F means fire. Not get ready to fire or light the fuse and run. Advance timing moves to 23.5 - 26.5 degrees not 35 degrees. 

The T mark is 0deg (TDC). The F mark is 8.5deg BTDC. The advancer mechanism rotates the points cam another 26.5deg for a total of 35deg. The left "/" is 32deg and the right "/" is 35deg. My OEM Honda Manual says Advance Timing is 35deg. Read the table a little higher up the same page.

1, The points are strobed at the // max. advance mark which produces a spark between 23-26 deg. BTDC.

Wrong. It is at 35deg. (F 8.5deg + // 26.5deg). The points are not strobed. The spark produced by the coil is strobed.

2. The electronic ign. is strobed at the // max. advance mark which produces a spark between ??-?? deg. before TDC.

It is 35deg. The electronic ign. is not strobed. The spark produced by the coil is strobed.

Spanner, The electronics systems do not use the points cam. The points cam is replaced on the advancer by their triggering device which is rotated N deg(s) CCW to cause the coil to fire a fully advanced spark at exactly 35deg BTDC.

For a long, long time most people thought the Earth was flat. I'm done.

[Holden]

The way I see it is that the when you set the timing with a strobe, you're basing it on the spark itself.  Whatever lag you've lost by going to an electronic ignition is automatically compensated for.  The point at which the spark fires is the same.  If this were actually a problem, I'm sure electronic ignition manufacturers could build delay into their systems.  Has anyone ever heard of a bike running worse with a properly functioning and installed electronic ignition?  I would guess there might be a case or two out there, but from what I've read on this and other sites, bikes run at least as well and usually better with an electronic ignition compared to properly adjusted points.  (I haven't installed an electronic ignition on my bike.)  Like I asked, has anyone ever heard a bike running worse because of the loss of point "lag"?