Topic: Thoughts about points

[BomberMann650]

My bike had a Dyna when I bought it, what a piece of crap that was! after countless and expensive towing bills and being stranded because the wussie Dyna couldn't handle the heat, I went back to points and Pandora has run flawlessly ever since. I wille adding a Hondaman ignition soon also. I'll never let another Dyna near my bike !

What is this hondaman ignition everyone is talking about? What's the bonus?

Member hondaman sells a transistor box that replaces the two condensers.  It's an affordable way to make sure you'll never have to deal with intermittent and panic-inducing condenser deaths again.

[Don R]

Fiddled with points for two years.  Fell plague to a diachi condenser failure.  Could tell when the 1/4 & 2/3 points were firing a couple degrees off of their 180 marks.
Didn't even want to go there with the yammie triple. 
The yammie's stock cdi ignition works, but the spark quality is not as impressive as uncle terry's miniature welder. 
Bloo runs really good on the pamco trigger.  Nice and smooth.  Well into the redline.
I have to remind myself not to push it.  There is no points bounce to "limit" the revs.  Since the rebuild it's running really well.  If I had the money to spend on better crank and valvetrain parts I'm sure that 550 motor would be able reach beyond 9krpm.  Due in part, to the accuracy of pamco's trigger.

When I get around to building another 550 engine, I'm gonna try to get a powerarc or cenex ignition.

The yammy triple I had needed a new fuse block, it had huge voltage drop.  I went to O'Rieleys and got a 4 wire in 4 wire out blade type fuse box. After that it fired right up. It's true an 80's bike is like an 80's car, electrically not so great.

[BomberMann650]

Fiddled with points for two years.  Fell plague to a diachi condenser failure.  Could tell when the 1/4 & 2/3 points were firing a couple degrees off of their 180 marks.
Didn't even want to go there with the yammie triple. 
The yammie's stock cdi ignition works, but the spark quality is not as impressive as uncle terry's miniature welder. 
Bloo runs really good on the pamco trigger.  Nice and smooth.  Well into the redline.
I have to remind myself not to push it.  There is no points bounce to "limit" the revs.  Since the rebuild it's running really well.  If I had the money to spend on better crank and valvetrain parts I'm sure that 550 motor would be able reach beyond 9krpm.  Due in part, to the accuracy of pamco's trigger.

When I get around to building another 550 engine, I'm gonna try to get a powerarc or cenex ignition.

The yammy triple I had needed a new fuse block, it had huge voltage drop.  I went to O'Rieleys and got a 4 wire in 4 wire out blade type fuse box. After that it fired right up. It's true an 80's bike is like an 80's car, electrically not so great.

76 750/3 but yeah.  Already shelled out the dough in a repop fusebox from the UK.  The original fell to pieces.

Wondering if there is something amiss in the plugs and caps.  But the bike does run.  Hopefully the speed shop will have the pipes assembled and carbs tuned in time for the DGR.

[Terry in Australia]

I'm yet to see a pic of a fat blue spark as bright as this from any points ignition, could one of you guys with a preference for points take a pic of yours so we can all see why you think they're better? This pic was taken during the day (late afternoon, from memory) so a pic taken in similar conditions would be a good comparison. Cheers, Terry.   

DSCN0659 by Terry Prendergast, on Flickr

[TwoTired]

The problem, Terry,  is that while your pic is quite showy.  I see no data relating that spark picture to any increase in hp or mpg on a stock engine.

No before or after data on same engine.

No data on what that spark cost in dollars or drain on the electrical system.

Further, spark pictures outside of a working combustion chamber are quite different than in an open atmosphere.  There's the physics bit about pressure and contents of the atmosphere within the spark channel.

The stock components did what they neede to do, and quite efficiently.

How efficient would you say you favored ignition is?  Can you measure it?

Cheers,

[BomberMann650]

What exactly was on that bike terry?  Aside from the electronic timing sensor?

[Terry in Australia]

What exactly was on that bike terry?  Aside from the electronic timing sensor?

G'Day Cowman, as per the original post, (on page 1) that's a 1970's Martek ignition with Dyna 3 Ohm coils that I installed on a Suzuki GS1000 "Bitsa" that I built a few years ago. That spark is typical of the fat blue spark that you should expect from an electronic ignition, sadly lacking in old school points ignitions. There's a very good reason that NO automotive manufacturer uses points ignitions nowadays............

[Terry in Australia]

The problem, Terry,  is that while your pic is quite showy.  I see no data relating that spark picture to any increase in hp or mpg on a stock engine.

No before or after data on same engine.

No data on what that spark cost in dollars or drain on the electrical system.

Further, spark pictures outside of a working combustion chamber are quite different than in an open atmosphere.  There's the physics bit about pressure and contents of the atmosphere within the spark channel.

The stock components did what they neede to do, and quite efficiently.

How efficient would you say you favored ignition is?  Can you measure it?

Cheers,

Well I'll have to bow to your expertise Lloyd, how more efficient would you say a points ignition was? Are you saying that a fat blue spark like the one in the pic outside of a combustion chamber would be somehow humbled by a typically much weaker spark from a points ignition inside the combustion chamber, due to some science that we're not aware of?

How many more BHP do you think a bike with a points ignition makes over one with an electronic ignition, producing a much stronger spark? How many more dollars does it cost to run a bike with an electronic ignition, even if it's worked perfectly in Geeto's bike for 20 years? Is the government somehow reducing the available power in modern motorcycles by insisting that manufacturers only install inefficient electronic ignitions? Is there a conspiracy that we should all be aware of? Do tell! 

As our technical "Expert" (and we all know what that means.......) I'm expecting a full report from you Lloyd, so get to it, no more questions, just answers please!    

[BomberMann650]

What exactly was on that bike terry?  Aside from the electronic timing sensor?

G'Day Cowman, as per the original post, (on page 1) that's a 1970's Martek ignition with Dyna 3 Ohm coils that I installed on a Suzuki GS1000 "Bitsa" that I built a few years ago. That spark is typical of the fat blue spark that you should expect from an electronic ignition, sadly lacking in old school points ignitions. There's a very good reason that NO automotive manufacturer uses points ignitions nowadays............

Well damn, now I'm wondering if my voltage problems are keeping the cdi and coils from getting better output.
Would old plug caps dim a spark?

[HondaMan]

What exactly was on that bike terry?  Aside from the electronic timing sensor?

G'Day Cowman, as per the original post, (on page 1) that's a 1970's Martek ignition with Dyna 3 Ohm coils that I installed on a Suzuki GS1000 "Bitsa" that I built a few years ago. That spark is typical of the fat blue spark that you should expect from an electronic ignition, sadly lacking in old school points ignitions. There's a very good reason that NO automotive manufacturer uses points ignitions nowadays............

Well damn, now I'm wondering if my voltage problems are keeping the cdi and coils from getting better output.
Would old plug caps dim a spark?

Yes. The plug caps on these bikes should be within 800 ohms of each other on any one coil, and we can get 5000 (5K and sometimes 10,000 (10K) types. These Hondas used 7500 ohm caps until 1975, then they went to 10,000 ohm caps. Today, we can use the 5000 ohm caps and the resistor-type sparkplugs (like DR8ES-L, DR8EA, DPR8EA9, XR24ES-U) to get another 2000 ohms into each plug circuit. This causes the spark to last longer, which these engines really like! The DPR8EA9 (and ND equivalent, which is slightly better) extend the tip further toward the piston, and makes the engine feel stronger in city traffic situations at lower RPM.

[TwoTired]

Well I'll have to bow to your expertise Lloyd, how more efficient would you say a points ignition was?

I don't need or want you to bow, Terry.  I'd like you to understand the technical matters.

I don't know the duty cycle or dwell of a Martek ignition trigger.  Do you?  Please relay for analysis.
The Dyna I learned about from Hondaman.  IIRC it has a duty cycle of about 270 degrees out of 360.  Meaning each coil is powered 270/360 or about 75% of the time, this is more than a points cam allows the points to be closed, which is 190/360, or about 53%.  The difference is that the dyna feeds power to the coils 22% more than what the points cam dictates.
So, the dyna trigger device is actually 22% less efficient than the stock system.  This could be justified if it could be proven that this 22% somehow translated to MPG or HP increases.  I've seen no data to support this.

Further, 3 ohm coils draw more power than 5 ohm coils.  This is another added energy draw from the system. on the order of 40%.  Again, with no HP or MPG improvement numbers, this is wasted energy consumption.

Are you saying that a fat blue spark like the one in the pic outside of a combustion chamber would be somehow humbled by a typically much weaker spark from a points ignition inside the combustion chamber, due to some science that we're not aware of? 

I can't explain why you aren't aware of the science.  I'm saying the fat blue spark you see outside the combustion chamber simply does not occur inside the combustion chamber, as it is a different environment, and the spark plug gap is far shorter than what you've depicted in the posted pic.
Do you set your spark plug gaps to 0.250 inch?  The way the coils and plugs work, is to raise the voltage to a point where the spark gap can be ionized and form a low resistance plasma channel. That's when current can flow and this event largely depletes further voltage build up within the spark gap.  In short, large voltages required to jump the 1/4 inch gap you show, just don't happen inside the combustion chamber, with gaps of .025 or even .035 inch gaps.

How many more BHP do you think a bike with a points ignition makes over one with an electronic ignition, producing a much stronger spark? 

Given no other changes outside of spark voltages, I expect it to have the same BHP, unless other mods are also made. 

How many more dollars does it cost to run a bike with an electronic ignition, even if it's worked perfectly in Geeto's bike for 20 years?

1- It hasn't worked perfectly, it's worked acceptably, imo.  Is he claiming HP and MPG improvements?  The Dyna is a 40 + year old inferior design that's being sales milked by marketing efforts.  Have you seen a new improved design from Dyna in the last 40 years?  Have electronic devices not improved in the last 40 years?
2- As far as dollars, it wasn't obtained for free was it?
3- I have point sets that are more than 20 years old on more than one bike that get near 50 MPG.  Apart from the minor inconvenience of periodic point reconditioning, where electronic has a clear advantage. I don't see how electronic would improve on that.  I'm clearly getting a good combustion burn with original components.

Is the government somehow reducing the available power in modern motorcycles by insisting that manufacturers only install inefficient electronic ignitions? Is there a conspiracy that we should all be aware of? Do tell! 

Well, that seems to have taken a bit of a silly bent.  Please tell us the passage where Big G as mandated electronic ignitions.  Perhaps a more solid straw man can be rendered.

But, if you look into e ignition systems as a whole on modern vehicles, you'll find a far different total system than the baby step units offered for our SOHC4s.

As our technical "Expert" (and we all know what that means.......) I'm expecting a full report from you Lloyd, so get to it, no more questions, just answers please!

Not sure you'd accept any answers I give you.  And, I'm not really interested in trading insults with you today.  Anyway, you are the one proposing E trigger ignitions are of great benefit.  Why isn't the onus on you to support the assertion with factual reasons why? 

However, I am surprised you even bother with an SOHC4 at all, as the sum of the era's technology is far inferior to modern offerings.  And a minuscule switch to an e ignition trigger device is not going to change the nature of the machine's combustion into modern equivalence.

G'Day!

[PeWe]

It would be nice if the advance could be tuned better and easier. One area for good idle, take offs and cruising speed. Another for full power and higher rpm.
Testing different springs, adjusting timing for best high or low. Correct spring setup might make both better.

[Deltarider]

Today, we can use the 5000 ohm caps and the resistor-type sparkplugs (like DR8ES-L, DR8EA, DPR8EA9, XR24ES-U) to get another 2000 ohms into each plug circuit. This causes the spark to last longer, which these engines really like!

First: all my resistor plugs, even new and whether they are NGK or Denso, show a resistance of at least 4kΩ and my used ND X24ESR-U vary from 6,9kΩ to even 8,5kΩ! In combination with 5kΩ resistor plug caps that would result in at least a 9kΩ resistance for a start and when I look at the resistance of the used NDs, I have reason to believe resistance will increase and may even double over time! It's a complaint, I've also heard on NGK "R" plugs, btw. In a dual ouput system like ours, that's at least 18kΩ in one circuit, which I consider a lot of dampening. I have no knowledge of any Honda dealer that advices to use both resistor plugs and resistor caps. On the contrary and again, one look at the increased resistance of my used Denso plugs tells me dealers are right in advicing owners of our bikes: either "R" plugs or resistor caps, not both. Their advice leaves a safe margin and that you need that margin, is what my used "R" plugs tell me. Then this: outside this forum I have not heard of this longer spark duration. I've searched - I'm open to the possibility and I'd love to see this effect - to learn more on this tuning of the spark duration. When I couldn't find anything, I went so far as to ask three experts (persons and institutions) but unfortunately have received no answers, let alone that they gave me a direction where I could find them. 3 X negative. What I do know however, is that a higher resistance transforms more energy into heat. This will result in less erosion at the sparkplug electrodes, which is a good thing (poor Terry). For other claims I've seen no evidence, but, again, I'd love to see it. From what I've seen, it seems to me the ignition and combustion of the mixture in the combustion chamber is a much too chaotic process to be able to predict that an increase in resistance will by definition result in a longer spark duration. Those that know for sure a longer spark duration will occur, can no doubt inform us where the increase in heat in the then used higher resistance comes from. I mean, there's something like the conservation of energy, isn't? Maybe oscilloscope images can tell us more?
It could be that Honda ment to have 10kΩ resistor plugcaps, but I doubt it. I once discovered a plugcap om mine, that seemed to be original and that read 10kΩ, but I cannot for the world determine whether it still had its original resistance or had deteriorated in the then over 40.000 kms. What I do know, is what one of my favourite manuals tells me. The 159 pages are in French and have been compiled in close cooperation with Honda. They advise de monter des antiparasites ayant une résistance inférieure à 8000 Ω.

[Terry in Australia]

Well I'll have to bow to your expertise Lloyd, how more efficient would you say a points ignition was?

I don't need or want you to bow, Terry.  I'd like you to understand the technical matters.

I don't know the duty cycle or dwell of a Martek ignition trigger.  Do you?  Please relay for analysis.
The Dyna I learned about from Hondaman.  IIRC it has a duty cycle of about 270 degrees out of 360.  Meaning each coil is powered 270/360 or about 75% of the time, this is more than a points cam allows the points to be closed, which is 190/360, or about 53%.  The difference is that the dyna feeds power to the coils 22% more than what the points cam dictates.
So, the dyna trigger device is actually 22% less efficient than the stock system.  This could be justified if it could be proven that this 22% somehow translated to MPG or HP increases.  I've seen no data to support this.

Further, 3 ohm coils draw more power than 5 ohm coils.  This is another added energy draw from the system. on the order of 40%.  Again, with no HP or MPG improvement numbers, this is wasted energy consumption.

Are you saying that a fat blue spark like the one in the pic outside of a combustion chamber would be somehow humbled by a typically much weaker spark from a points ignition inside the combustion chamber, due to some science that we're not aware of? 

I can't explain why you aren't aware of the science.  I'm saying the fat blue spark you see outside the combustion chamber simply does not occur inside the combustion chamber, as it is a different environment, and the spark plug gap is far shorter than what you've depicted in the posted pic.
Do you set your spark plug gaps to 0.250 inch?  The way the coils and plugs work, is to raise the voltage to a point where the spark gap can be ionized and form a low resistance plasma channel. That's when current can flow and this event largely depletes further voltage build up within the spark gap.  In short, large voltages required to jump the 1/4 inch gap you show, just don't happen inside the combustion chamber, with gaps of .025 or even .035 inch gaps.

How many more BHP do you think a bike with a points ignition makes over one with an electronic ignition, producing a much stronger spark? 

Given no other changes outside of spark voltages, I expect it to have the same BHP, unless other mods are also made. 

How many more dollars does it cost to run a bike with an electronic ignition, even if it's worked perfectly in Geeto's bike for 20 years?

1- It hasn't worked perfectly, it's worked acceptably, imo.  Is he claiming HP and MPG improvements?  The Dyna is a 40 + year old inferior design that's being sales milked by marketing efforts.  Have you seen a new improved design from Dyna in the last 40 years?  Have electronic devices not improved in the last 40 years?
2- As far as dollars, it wasn't obtained for free was it?
3- I have point sets that are more than 20 years old on more than one bike that get near 50 MPG.  Apart from the minor inconvenience of periodic point reconditioning, where electronic has a clear advantage. I don't see how electronic would improve on that.  I'm clearly getting a good combustion burn with original components.

Is the government somehow reducing the available power in modern motorcycles by insisting that manufacturers only install inefficient electronic ignitions? Is there a conspiracy that we should all be aware of? Do tell! 

Well, that seems to have taken a bit of a silly bent.  Please tell us the passage where Big G as mandated electronic ignitions.  Perhaps a more solid straw man can be rendered.

But, if you look into e ignition systems as a whole on modern vehicles, you'll find a far different total system than the baby step units offered for our SOHC4s.

As our technical "Expert" (and we all know what that means.......) I'm expecting a full report from you Lloyd, so get to it, no more questions, just answers please!

Not sure you'd accept any answers I give you.  And, I'm not really interested in trading insults with you today.  Anyway, you are the one proposing E trigger ignitions are of great benefit.  Why isn't the onus on you to support the assertion with factual reasons why? 

However, I am surprised you even bother with an SOHC4 at all, as the sum of the era's technology is far inferior to modern offerings.  And a minuscule switch to an e ignition trigger device is not going to change the nature of the machine's combustion into modern equivalence.

G'Day!

Wow, what a read! Not much real info to take away from it, but I appreciate your efforts. Why do I bother with CB750's? Good question Lloyd, and quite a simple one, even though I currently own 14 bikes, several with at least twice the power of a CB750, I'm a child of the 70's, and still remember when you could buy a new Triumph, BSA or Norton, but the bike that was really rocking everyone's world was the CB750.

I bought a fugly NOS 1975 CB750F in 1978 (the dealers couldn't move them without huge discounts) then a K1 in 1980 which was a great bike, installed my first Martek ignition on it, then happily rode it for another 6 years until I sold it (bought a Z1) and once I installed that EI, I never took the points cover off again. Since then I've owned probably 20 CB750's, and I like to think they all left in a much better state than when I dragged them home.

I'm currently building a K2 "Bitsa" entirely from parts, and once it's done, I'll start on my 1969 K0. I'm looking forward to installing the Dyna III ignition I bought from Kyle (Chewbacca here) so I can post a pic of the fat blue spark it kicks out! Here's a vid of a Briggs engine with a glass cylinder head, very interesting, you can clearly see the spark, and when they turn the idle right down it reminds me of the time I installed a Martek on a Suzy GS750, and was able to have it happily idle away @ 200 RPM! Cheers, Terry.    

[BomberMann650]

Fellas Fellas Fellas!  Play nice, have a beer!

[754]

 If I had more money, a cell phone that works in USA, and a credit card, then I might run electronic ignition.
But that is unlikely, and I dont expect anyone to pay my way.
I have the e  ignition, but no spares.

The sohc riders that have all of the first line, are not riding their bikes anywhere that I know of....?    SO i dont want to end up like them.

[AirCanuck]

If I had more money, a cell phone that works in USA, and a credit card, then I might run electronic ignition.
But that is unlikely, and I dont expect anyone to pay my way.
I have the e  ignition, but no spares.

The sohc riders that have all of the first line, are not riding their bikes anywhere that I know of....?    SO i dont want to end up like them.

Can you explain that last line?

[Terry in Australia]

I think Frank's saying that only unsuccessful people regularly ride their SOHC4's. You know, poor but honest knights of the road, penniless bums who found their bikes leaning against a tree and keep them running using gas produced by food they find in dumpsters along the road to wisdom that only people too poor to own a cell phone, or be trusted with a credit card, can achieve. (most jails are full of them)

[AirCanuck]

I think Frank's saying that only unsuccessful people regularly ride their SOHC4's. You know, poor but honest knights of the road, penniless bums who found their bikes leaning against a tree and keep it running using gas produced by food they find in dumpsters along the road to wisdom that only people too poor to own a cell phone, or be trusted with a credit card, can achieve. (most jails are full of them)

Ah. Quite clear....

[Gene]

Terry, I love you, not that there's anything wrong with that, but you can be a real prick

You know what we haven't talked about in a minute? Head Cheese.

[Terry in Australia]

Thanks Gene, the Australian government is currently spending 122 million bucks sending us all out a survey so we can tell them if the law should be changed to allow gay people to get married to each other? Sadly only yes/no answers will be accepted, so I can't write, "Yes, but only as long as it's between two chicks, and they're hot"..........    

[Gene]

Thanks Gene, the Australian government is currently spending 122 million bucks sending us all out a survey so we can tell them if the law should be changed to allow gay people to get married to each other? Sadly only yes/no answers will be accepted, so I can't write, "Yes, but only as long as it's between two chicks, and they're hot"..........    

Ok. Still funny, but still a prick.
I'll lay off the legislation argument because I don't feckin care who is married to who and either way, haz nothing to do with points. Well, wait a sec . . . not THOSE points.

[Gene]

P.S. ya Aussie rat bastard *sigh* I do miss the down under.

[Terry in Australia]

Ha ha, you're gonna have to do better than that Gene, my wife calls me worse names than that!

[Gene]

Ha ha, you're gonna have to do better than that Gene, my wife calls me worse names than that!

When we meet, my friend, I promise to call you all sorts of horrible things. My Father was a sailor, after all, and left his vocabulary with me. Not meant for public forums.