wing tips #3 condensors

Tips and Recommendations from Guru Mike Nixon

Moderator: Whiskerfish

Post Reply
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

wing tips #3 condensors

#1

Post by mikenixon »

Condensors
The GL1000's lowly points condensor has much to teach us. Many believe that the condensor's role is to reduce points arcing and the resulting shortened points life. But while arcing is indeed reduced, this is not the condensor's reason for being. The condensor's real job is much more important than this. Here's what it actually does. Before the points open by means of the points cam the ignition coil is filled with the battery's voltage. The coil is "hot". When the points open, the ignition coil's primary winding shuts down suddenly, causing its magnetic field to collapse, which induces the coil's secondary winding to suddenly build and produce the high voltage needed for spark. Here's the key. The speed with which the primary collapses is one of the ingredients that makes the the secondary's pulse dramatic and powerful. Fast is good. What the condensor does is ensure the primary's clean, sharp, and sudden collapse. When the points open, they try to fire a spark across themselves just as if they were the spark plug. It's understandable. A lot of energy is being held in the winding, and the sudden disconnect is a pretty forceful event. By not allowing the points to throw a huge spark, the condensor reserves the primary winding's energy, permitting it to be spent only on inducing the secondary winding. The condensor makes the points break their circuit as suddenly, cleanly, and abruptly as possible, thereby ensuring the strongest possible primary field collapse, with the most advantageous mutual interaction between primary and secondary windings. This is really the condensor's job, to boost primary collapse. An interesting note: your bike will run without the condensors. But not very well. It will have a very low rpm rev limiter. The greatly reduced primary winding effectiveness means a huge loss of the secondary's spark voltage, and by 3,000 rpm there just isn't enough to further support combustion.

The transistor
So the condensor's real role in the GL1000 is to make the ignition coil's primary collapse as clean and as sudden as possible, thereby assuring the maximum effect on the secondary winding's spark production. Interestingly, we can observe this very same principle at work in the later Wings' electronic ignitions. Being simply transistorized versions of the exact same ignition, the later bike's transistorized system works in exactly the same way as well. The only difference is the GL1000's points are replaced by a pulser and by a transistor in the GL1100. The transistor's job is the same as the points', to cut the coil's primay feed, causing the winding's magnetic field to collapse, inducing the coil's secondary winding. Now the intereresting part. As the transistor ages, its switching ability slows, and the break becomes less abrupt, not as sudden or as clean, and spark energy suffers. Like a points system with a bad condensor. This is precisely why fitting ProCom aftermarket replacement ignitors makes a bike feel a bit better running even when no performance issue was observed before the replacement. The new transistors are snapping the coils off faster and cleaner, resulting in more vigorous spark and an improvement in combustion that results in increased throttle response and torque.
Last edited by mikenixon on Tue Mar 12, 2019 8:12 pm, edited 1 time in total.
User avatar
ericheath
Honored Life Member
Honored Life Member
Posts: 9580
Joined: Wed Jul 29, 2009 11:20 am
Location: Winnipeg, Manituba

Re: wing tips #3

#2

Post by ericheath »

So, in essence, replacing the transistors is similar to a slight timing advance, except the timing advance portion is in the speed the transistors do their job??

Do condensers slow with age?
User avatar
Whiskerfish
President
President
Posts: 36852
Joined: Thu Feb 16, 2006 9:34 pm
My Album: http://www.ngwclub.com/gallery/v/wingmans/whiskerfish/
Location: Norfolk Va

Re: wing tips #3

#3

Post by Whiskerfish »

Excellent read Mike! I have tried to explain this several times over the years but did not have quite enough knowledge to do so ( and probably did so incorrectly!) Can you expound on the function at the closing end of the spark cycle? From the reading I have done I get the impression that the Cap will retain some charge and provides a clean end to the spark.

I suspect the points protection part of the job is what gets focused on as it is often the catalyst to change the caps.

ericheath wrote:SNIP

Do condensers slow with age?
No. "To the best of my knowledge" the low end Condensers typically do not have a soft failure mode. Some of the newer metal based ones do a have a potential for degraded operation but ours generally work or don't work. If anyone suspected poor operation I would first verify the ground system. The case of the Cap should be a dead short to the negative terminal of the battery. Any resistance there will reduce the Cap's efficiency. Checking that resistance should be a part of any ignition troubleshooting.
"Agreement is not a requirement for Respect" CDR Michael Smith USN (Ret) 2017
"The book is wrong, this whole Conclusion is Fallacious" River Tam
2008 GL1800 IIIA "TH3DOG"
1975/6/7/8/9 Arthur Fulmer Dressed Road bike
1975 Naked Noisy and Nasty in town bike
and a whole garage full of possibilities!!

Psst. oh and by the way CHANGE YOUR BELTS!!!!
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#4

Post by mikenixon »

ericheath wrote:So, in essence, replacing the transistors is similar to a slight timing advance, except the timing advance portion is in the speed the transistors do their job??
No, when we speak of ignition voltage rise, we're talking thousands of a second (mS). Though significant in ignition operation, it is too subtle to show on a degree wheel.

The corrollary between the condensor and the transistor is only in respect to how each affects the rapidity of the primary circuit's collapse. Beyond that, there is no real similarity. The touch point is the more sudden the collapse, the better the output. The condensor guards the collapse, ensuring it and ensuring good output. The tansistor doesn't guard its system's collapse, but its gradual aging slows it, thus affecting output.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#5

Post by mikenixon »

Whiskerfish wrote:Excellent read Mike! I have tried to explain this several times over the years but did not have quite enough knowledge to do so ( and probably did so incorrectly!) Can you expound on the function at the closing end of the spark cycle? From the reading I have done I get the impression that the Cap will retain some charge and provides a clean end to the spark.

I suspect the points protection part of the job is what gets focused on as it is often the catalyst to change the caps.
Thanks, WF. Yeah, condensors are out of sight/out of mind for most of us, looming on the radar only when they die, which is not in my experience very common. Interesting note: On another forum, a member related how against his intuition he replaced his aftermarket condensors on his 750 with the 42 year old OEM takeoffs he had fortunately saved, and it cured his bike's hesitation, illustrating two things: first, that condensors do in fact fail (and as you say, it's sudden, not gradual), and second, that as my experience suggested, Honda's original condensors are superior quality.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#6

Post by mikenixon »

Whiskerfish wrote:Can you expound on the function at the closing end of the spark cycle? From the reading I have done I get the impression that the Cap will retain some charge and provides a clean end to the spark.
You probably know more about that than I do. Though I owned an ignition oscilliscope (Heathkit, purchased and assembled in 1972, sold in the late 1990s) and used it solely to study and compare ignitions, I didn't run across this aspect. It was a fascinating exploration however.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#7

Post by mikenixon »

Let me also add this: I really like standard Kettering ignition! I just acquired a real barn find low-mile, 90 percent 1973 CB500 four and am really digging how capable the stock ignition is. It's a simple, well-performing system. Naturally, I am not looking for the programmable timing, adjustable rpm limiting and other benefits of modern ignition.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#8

Post by mikenixon »

Whiskerfish wrote:If anyone suspected poor operation I would first verify the ground system. The case of the Cap should be a dead short to the negative terminal of the battery. Any resistance there will reduce the Cap's efficiency. Checking that resistance should be a part of any ignition troubleshooting.
Yup. I like that suggestion.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#9

Post by mikenixon »

Whiskerfish wrote:...a clean end to the spark.
One of the things observers of ignition testing equipment --particularly oscilloscpes -- learn is that the end of the spark is not real sudden. Almost, but not quite. Pardon me while I use layman's terms, but it seems that when the secondary winding's voltage has spent itself, and thus the spark stops, two interesting things happen. One, the primary, seeing the secondary's signoff, tries to reverse induce, hopelessly as it's pretty feeble due to this being only residual. But thiugh residual, it is enough to be detected by that wonderful tool the peak voltage adapter and used in ignition troubleshooting. More about that at another time. But second, the other thing that happens after spark is the abrupt loss of spark is felt by the coil as a sudden loss of load (the plug is the load) and thus the quickly ebbing secondary voltage, lacking a load, instantly climbs again, just a little, in what looks like an attempt to again ionize the plug's gap. This shows on the scope waveform as a small spike. It doesn't do anything and certainly doesn't re-spark because the voltage just isn't there and it's merely the surge caused by the load being removed. But it's interesting and your comment reminded me of it. Finally, after this last "hurrah" the secondary voltage does indeed drop like a rock, as illustrated by an almost perfectly vertical line to zero on the scope.


Image
Last edited by mikenixon on Mon May 14, 2018 11:08 am, edited 1 time in total.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#10

Post by mikenixon »

I was saving this for later but it seems appropriate for now. :)

Crafty coils
Those of you who understand the working of a dual output ignition coil, such as are found on the Gold Wing, will appreciate this. When a mechanics instructor, I liked doing demos. One of them was a way to illustrate the power of ignition. I would take a Gold Wing ignition coil and wire its primary side through a metal shop stool and power it up through a vibrating type coil tester. Then after turning the room's lights off I would connect the battery and away we go. Nice Tesla-looking sparks about two inches long leaping spectacularly to my stool! Purple, crackling sparks! One of the ways I got such a powerful spark was I wired the dual output coil's second, unused plug lead back to the primary, thereby increasing the spark voltage (I would guess some 30-40 percent) by making a coil designed for two plugs fire just one. It worked and it worked well. Since those days I have often thought about replacing the two dual output coils on a four-cylinder Japanese bike with four dual output coils modified in the manner just described, turning them into four boosted single-output coils. The problem of course is, as in everything, there's no free lunch. For one thing, the main reason manufacturers use dual output coils is to save space on the bike. So where is the room for two more? But that demo franken-spark dual output coil just had an edgy kind of appeal to me. A thrill a minute.
User avatar
Whiskerfish
President
President
Posts: 36852
Joined: Thu Feb 16, 2006 9:34 pm
My Album: http://www.ngwclub.com/gallery/v/wingmans/whiskerfish/
Location: Norfolk Va

Re: wing tips #3

#11

Post by Whiskerfish »

Interesting experiment with the coils action1 action1 action1 I can not imagine the life expectancy would be great operating at such high power settings kind of like over driving an amp?? I spent one semester in HS doing a self study of high output coils and spark generation but that was a Very long time ago.

I forget the proper term ( feedback, echo, reflection, whatever) for the surge created in the pri when the secondary is spent but often wondered about the Capacitors function in that as well. I know it can not act as a diode would but would think it provides some protection for the points acting more like a dampner? And after that would it not apply that stored energy toward the build of the next cycle?
But thiugh residual, it is enough to be detected by that wonderful tool the peak voltage adapter and used in ignition troubleshooting. More about that at another time.
I will look forward to that!!
"Agreement is not a requirement for Respect" CDR Michael Smith USN (Ret) 2017
"The book is wrong, this whole Conclusion is Fallacious" River Tam
2008 GL1800 IIIA "TH3DOG"
1975/6/7/8/9 Arthur Fulmer Dressed Road bike
1975 Naked Noisy and Nasty in town bike
and a whole garage full of possibilities!!

Psst. oh and by the way CHANGE YOUR BELTS!!!!
User avatar
5speed
Honored Life Member
Honored Life Member
Posts: 5311
Joined: Sat Jul 11, 2015 2:37 pm
Location: Nova Scotia Canada

Re: wing tips #3

#12

Post by 5speed »

mikenixon wrote: This is precisely why fitting ProCom aftermarket replacement ignitors makes a bike feel a bit better running even when no performance issue was observed before the replacement. The new transistors are snapping the coils off faster and cleaner, resulting in more vigorous spark and an improvement in combustion that results in increased throttle response and torque.
Is this something I should consider doing on my 82?
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#13

Post by mikenixon »

5speed wrote:
mikenixon wrote: This is precisely why fitting ProCom aftermarket replacement ignitors makes a bike feel a bit better running even when no performance issue was observed before the replacement. The new transistors are snapping the coils off faster and cleaner, resulting in more vigorous spark and an improvement in combustion that results in increased throttle response and torque.
Is this something I should consider doing on my 82?
It's entirely an elective thing if your bike is running decently now. The CBX and DOHC guys are going to them because their 30+ yr old igniters (transistor housings, "spark boxes" per Honda) are going out. But, and the point of my mention, even riders whose bikes weren't noticeably misbehaving have reported a just-perceptible improvement in acceleration using them. And I attribute that to newer and possibly more advanced transistors that are doubtless performing their switching off function more rapidly and cleanly. The GL1100 has the same spark units, but they don't seem to be failing at the same rate as those on the sportier bikes. By the way, if you want your spark boxes to live long, avoid starting the bike with a low battery, and keep the boxes' connecting plug terminals clean, particularly the green ground wire. Both of these problems kill the spark units.
User avatar
5speed
Honored Life Member
Honored Life Member
Posts: 5311
Joined: Sat Jul 11, 2015 2:37 pm
Location: Nova Scotia Canada

Re: wing tips #3

#14

Post by 5speed »

mikenixon wrote:
5speed wrote:
mikenixon wrote: This is precisely why fitting ProCom aftermarket replacement ignitors makes a bike feel a bit better running even when no performance issue was observed before the replacement. The new transistors are snapping the coils off faster and cleaner, resulting in more vigorous spark and an improvement in combustion that results in increased throttle response and torque.
Is this something I should consider doing on my 82?
It's entirely an elective thing if your bike is running decently now. The CBX and DOHC guys are going to them because their 30+ yr old igniters (transistor housings, "spark boxes" per Honda) are going out. But, and the point of my mention, even riders whose bikes weren't noticeably misbehaving have reported a just-perceptible improvement in acceleration using them. And I attribute that to newer and possibly more advanced transistors that are doubtless performing their switching off function more rapidly and cleanly. The GL1100 has the same spark units, but they don't seem to be failing at the same rate as those on the sportier bikes. By the way, if you want your spark boxes to live long, avoid starting the bike with a low battery, and keep the boxes' connecting plug terminals clean, particularly the green ground wire. Both of these problems kill the spark units.
Thanks for the reply Mike.
I will add it to the list along with checking those connections.
User avatar
mikenixon
Early 'Wing Guru
Early 'Wing Guru
Posts: 997
Joined: Thu Dec 10, 2009 1:51 am
Location: Prescott, AZ
Contact:

Re: wing tips #3

#15

Post by mikenixon »

Whiskerfish wrote:I forget the proper term ( feedback, echo, reflection, whatever) for the surge created in the pri when the secondary is spent but often wondered about the Capacitors function in that as well. I know it can not act as a diode would but would think it provides some protection for the points acting more like a dampner? And after that would it not apply that stored energy toward the build of the next cycle?
I've never thought of it that way, but you could be right. :)
Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “Mike Nixon's Spot”