Author Topic: Thoughts about points  (Read 48743 times)

0 Members and 1 Guest are viewing this topic.

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 16,375
  • Bike almost back to the 70's 2015
Re: Thoughts about points
« Reply #150 on: September 26, 2017, 06:53:25 AM »
Dyno run cost 100USD here. A little bit more when doing several after each other when the dyno can only check A/F ratio on 2 simultaneously.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967


Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,046
Re: Thoughts about points
« Reply #152 on: September 26, 2017, 09:48:45 AM »
Now let's talk gas mileage vs ignition system..is there the vast noticeable improvement?
I look for something wrong if I ever get less than 45 to the US gallon. I got 55 mpg most of the time on the road. Using points.  I ran paper thru them to clean them, set the gap with feeler guage, and static timed by eye.
« Last Edit: September 26, 2017, 09:18:35 PM by 754 »
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 16,375
  • Bike almost back to the 70's 2015
Re: Thoughts about points
« Reply #153 on: September 26, 2017, 11:09:33 AM »
Frank, I'm sure you will hear when timed correctly at idle, right?  Paper thru points as a feeler gauge seems to be a quick working setup.
Strange that Terry does not use that procedure on his Hillbilly Redneck bike :)

Only sloppy springs that can mess it up. This affect the electronic ignitions too. I used Pamco when I had problems with the too early advance due to the springs.
« Last Edit: September 26, 2017, 11:17:30 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline ofreen

  • Old Timer
  • ******
  • Posts: 4,196
Re: Thoughts about points
« Reply #154 on: September 26, 2017, 04:42:54 PM »
it was very rare for them to short out and die, as the SCR is about as reliable an electronic part as a 1911 Glock pistol. ;)

FIFY  ;D

This thread has me thinking. I should ditch the Dyna S that has been in my 750 for last 140,000+ miles as it is liable to fail at anytime and leave me in the lurch. Fat blue sparks are way over-rated anyway. So what if when I throw a timing light on there it is rock steady? And it is not like I am trying to start the bike in 20 degree weather evey day.  And spark plugs are cheap, so what if they seem to last forever with the Dyna (as long as the caps are good.) I know that points plate is around somewhere even though I haven't seen it for almost 30 years because I never throw anything away. The Dyna has paid for itself many times over but it time to face reality and concede it is time to go with what is proven rather than that newfangled contraption I foolishly installed so long ago. ;)
Greg
'75 CB750F

"I would rather have questions I cannot answer than answers I cannot question." - Dr. Wei-Hock Soon

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,046
Re: Thoughts about points
« Reply #155 on: September 26, 2017, 10:20:51 PM »
 I am seeing both sides have very valid points.
What I am finding odd is the electronic guys to some xtent seem offended that we are not trotting off to take advantage of the better  way..
 But speaking for myself only, when I start finding it too tedious, I too may try an electronic..but first, it would have to become tedious, and my supply of spares, is not dwindlng nor wearing out.
 But hey we are hearing you on the "better way"
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline BomberMann650

  • Holy Cow! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 6,581
  • Dr. Bovinestein iBa#80333
Re: Thoughts about points
« Reply #156 on: September 26, 2017, 10:52:18 PM »
The smoothness of the top end is better with electronic ignition.

That's my favorite part.  Revs up top feel like they'd let you take them just a little bit further.

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 16,375
  • Bike almost back to the 70's 2015
Re: Thoughts about points
« Reply #157 on: September 27, 2017, 03:07:21 AM »
I'm sure that electronic ignitions are really good, no doubts about that.

I think that the old points have got a too bad reputation due to wrong setting, bad quality etc (Daichii). If a bike runs with a not or wrong adjusted ignition (points need to be lubricated) it will run bad.
Then install a new Dyna system or similar, the bike will run really fine as it had done if the points had been adjusted or the condensors replaced.

Old points will probably need more service. But seldom stop the bike as some has whitnessed with EI like some Dyna-S that suddenly could fail.
All my ignition tunings were intiated by engine tear downs, cam change etc. Not that the points had changed.

I'll get my bike as good tuned as possible carb wise. Then check the ouput on Dyno, change the ignition to my Dyna-S and see if the dyno will change the curves. Streetability is very important too with smooth take offs to riding in low speed then increase with some sudden WOT.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

AirCanuck

  • Guest
Re: Thoughts about points
« Reply #158 on: September 27, 2017, 04:12:19 AM »
I am seeing both sides have very valid points.
What I am finding odd is the electronic guys to some xtent seem offended that we are not trotting off to take advantage of the better  way..
 But speaking for myself only, when I start finding it too tedious, I too may try an electronic..but first, it would have to become tedious, and my supply of spares, is not dwindlng nor wearing out.
 But hey we are hearing you on the "better way"

Agreed... if there's one thing I've learned from this thread it's that's very experienced riders claim that both methods are the holy grail for reliability, and rarely fail, while having anecdotes about the other type failing.

Points advantage seems to be the ease of replacing spares if they break and the unlikelihood of them failing, but they require regular maintenance.

electronic is set and forget and makes a nice fat blue spark but if it fails you're done, and it can overheat.

Both seem good to me...

Offline rotortiller

  • Expert
  • ****
  • Posts: 945
Re: Thoughts about points
« Reply #159 on: September 27, 2017, 04:29:49 AM »
After employing this for a couple of years until failure I will be going to a more sensible electronic system. For now the points are back in and working the same (as the points activated WB). Basically the better unit is out of the elements and dry, non-mechanical, cheap to buy, modern, takes up no extra space, and the wiring is simpler.




Offline ofreen

  • Old Timer
  • ******
  • Posts: 4,196
Re: Thoughts about points
« Reply #160 on: September 27, 2017, 05:20:53 AM »
What I am finding odd is the electronic guys to some xtent seem offended that we are not trotting off to take advantage of the better  way.

I hope no one got the impression it matters enough to me what ignition system someone prefers to run for it to offend me. To me, it boils down to how much, where and when you are going to ride the bike. Kind of like o-ring chains. I ride my 750 10 months out of year in all kinds of weather. Used to be 12 months a year until they started slathering the roads with salt and mag chloride in the winter whether it snows or not. If I were using it for occasional weekend rides like most of these bikes are used for these days I'd stick with points, just like the ones that are in my 68 Nova and 65 F250.  They still work fine, but if I were driving them every day, I'd probably ditch the points in those too. Kind of like how I quit putting bias ply tires on them years ago. ;) 

With the quality control issues Dyna seems to be having these days, I'd probably check out Hondaman's ignition.
Greg
'75 CB750F

"I would rather have questions I cannot answer than answers I cannot question." - Dr. Wei-Hock Soon

Offline Geeto67

  • A grumpy
  • Old Timer
  • ******
  • Posts: 2,822
Re: Thoughts about points
« Reply #161 on: September 27, 2017, 06:48:45 AM »

electronic is set and forget and makes a nice fat blue spark but if it fails you're done, and it can overheat.
 

Carry a spare points plate in your breakdown kit. you do have a breakdown kit don't you?

I have only ever had one ignition trigger failure while riding a motorcycle, it was on points and it was because my points cover had been mangled so it was open and I got caught in a rain storm. Wet points don't fire. wasn't the points fault, I had just had an accident with the bike and I hadn't sourced a new points cover yet.

If you do something wrong installing them or maintaining them both have the ability to make you walk. years ago I accidentally deleted a resistor wire installing a hot coil in my GTO and I burned through a set of points in record time (GM points distributors use 8 volts, the resistor wire knocks it down from 12v). I switched to a petronix electronic ignition and an MSD digital 6 box only to have the msd box go bad in 2015 (at least I got 17 years of service out of it).

The only thing I personally object to is people waxing poetic about points like it is some kind of special man and machine magical bond. It's a set of clappers that makes spark.
Maintenance Matters Most

Offline Gene

  • Chat enuf you too can be a
  • Master
  • *****
  • Posts: 2,050
  • One bike is enuf, change my mind
Re: Thoughts about points
« Reply #162 on: September 27, 2017, 12:40:53 PM »
What I am finding odd is the electronic guys to some xtent seem offended that we are not trotting off to take advantage of the better  way.

I hope no one got the impression it matters enough to me what ignition system someone prefers to run for it to offend me. To me, it boils down to how much, where and when you are going to ride the bike. Kind of like o-ring chains. I ride my 750 10 months out of year in all kinds of weather. Used to be 12 months a year until they started slathering the roads with salt and mag chloride in the winter whether it snows or not. If I were using it for occasional weekend rides like most of these bikes are used for these days I'd stick with points, just like the ones that are in my 68 Nova and 65 F250.  They still work fine, but if I were driving them every day, I'd probably ditch the points in those too. Kind of like how I quit putting bias ply tires on them years ago. ;) 

With the quality control issues Dyna seems to be having these days, I'd probably check out Hondaman's ignition.

I'm with you here, I don't have a strong opinion either way never having used the E ignition of any sort. I ride everyday with points and have never had to fuss with the 750. The 550 I have, but it's been user error on my part.

The 360 I had, on the other hand, required constant attention.

But really - whatever works. I see the appeal of the E, maybe I should get one and try it out.
*1973 CB750K3 (Bow)

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,802
Re: Thoughts about points
« Reply #163 on: September 27, 2017, 12:47:20 PM »
electronic is set and forget and makes a nice fat blue spark but if it fails you're done, and it can overheat.

The "fat blue spark" is certainly a visual feast.  OOO - AAHH.   And quite attractive to those who are easily amused with shinny things.  But, it is not solely the result of replacing points with a transistor switch.  The coils are fed with 12V in either case.
The spark needs other components to make spark, like coils for example, and the actual color of the spark is dependent on the composition/ particle contamination of the atmosphere around the plasma channel that has formed.  How do you think that neon signs can emit different colors when fed an identical electrical charge?

The step up ratio of the coils (remember, that is also part of the ignition system?)  determines how much the 12v can be multiplied to a firing voltage.
The actual voltage attained is determined by how big a gap that is jumped.  Larger gaps need a higher initial voltage to bridge the gap.

A half inch gap jumped outside the combustion chamber, is fricking meaningless to what happens inside a running engine with spark gaps of .025 of an inch. 

To make yourself visually satisfied, you can put 3 ohm or less coils on a points trigger system and get that very same fat blue spark (outside the combustion chamber) that is irrationally idolized by many.

No one here, has actually relayed information about how a "fat Blue Spark" has any translation to HP or MPG improvement in a stock bike, only that it "feels" almost as impressive as it is visually appealing.  There is no science in these anecdotal reports.  And science has proven that humans are irrationally convinced that their purchases do what they want rather than what they actually provide.  It's a self reinforcement human trait.  And one reason why anecdotal reports are so famously unreliable.

If it's louder, its faster.  No need to actually measure it.  If I believe the bike is faster, then it feels like it, too.  It's what I expect and want.  That is what the "spark picture" is selling.  Further, "since I purchased it, if everyone else does too, it justifies my cash outlay".  (More human base psychology).

Picture of a "fat Blue Spark" is just eyewash.  If you are superficial enough to be swayed by such flashy images, you deserve to have your wallet further depleted.

The "electronic ignition" buzzwords are just a convenient marketing type label misapplied to a single ignition component.
Adding one or two transistors to replace point contacts, in no way approaches the modern vehicle equivalent to state of the art electronic ignition systems.  Such comparisons are disigenuous at best.

If you want to feed the greed of suppliers intent on extracting as much as they can from you, go ahead.
Also, if you are inept or unwilling to properly set a points system up to have the same HP and mileage as your friendly money splurger, go ahead.
Just don't feel you HAVE to buy an "electronic ignition" component, because that's what you need to be popular or be in with the "in crowd".
Your SOHC4 will run fine with the point system Honda provided.  All mine do.

I still maintain that the Dyna-S is an unworthy power hog design.  I'm glad I didn't buy it when seriously tempted in the 80's.

If you are irresistibly attracted to shinny things this should keep you occupied for hours.   ;D

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline BomberMann650

  • Holy Cow! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 6,581
  • Dr. Bovinestein iBa#80333
Re: Thoughts about points
« Reply #164 on: September 27, 2017, 01:16:50 PM »
Long time ago my old man and I were witness to the sales pitch like tt scorns.

Man in a sales tent with an old v8 luxury car was selling coil power booster gadgets.
Of course he'd memorized the usual sales pitch "power, performance, economy"

But he went on to the "bigger better spark" display.  Had a little setup to show everyone what a spark would do to a piece of paper.  With and without his little gadget.  Stock part lit the paper on fire.  The gadget changed the spark and it burned a clean hole right through.  (Don't ask me to explain the science there.)

But the running motor test.  Without the gadget, it was a runner.  Little sluggish even.  Carbureted v8 yay. He'd start pulling plug wires off.  1 wire, motor started limpin.  2 wires, shut down.
With the gadget, motor ran with a bit more pep.  Then he pulled plug wires, 1, 2, 3 - motor still running.  On 5 cylinders.

Point of the story - maybe there is something to still take away from a "spark in atmosphere" test.  But certainly much to understand about the nature of coil saturation/output powers/quality.  Which begins with your timing sensor!

If you get better more consistent signal from the crank to the coils - that would be a veritable improvement to a points system.  Electronic or mechanical, it is important.

Now one thing I'm not understanding in this thread - why is the dyna the common denominator?  There are much more technologically advanced ignitions available for CB motorbikes.  An electronically controlled variable timing curve system is proven - time and time again - to be extremely effective (and reliable) at getting the most performance from whatever motor it is tailored to.  In a competitive field where rider style is a thing, a bespoke ignition timing system is a competitive advantage.  (Just don't ask me to explain the science)

Speaking of competition, why haven't magnetos come up in discussion?

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,802
Re: Thoughts about points
« Reply #165 on: September 27, 2017, 03:03:24 PM »
If you get better more consistent signal from the crank to the coils - that would be a veritable improvement to a points system.  Electronic or mechanical, it is important.

How will you prove or disprove your "if / then" statement?  I'm wondering if innuendo is enough?  I don't know why you think points have any inherent instability.  Perhaps if measured in nanoseconds.  The engine doesn't need or will notice any time increments that small.

Now one thing I'm not understanding in this thread - why is the dyna the common denominator? 

I think Dyna was the most popular cash cow in the EI trigger offerings.  They had excellent marketing.  Pity their design was lacking in sophistication.

Speaking of competition, why haven't magnetos come up in discussion?

Er, they have points.


Anyway,
For a conversion, I really favored the CD ignition systems.  They would take your original coil and up the input voltage to 300-400 Volts.  Now THAT would make even worn out spark plugs fire like new.  They also provided multiple spark benefits with low currents for the spark electrodes.   This is important for spark plug electrode life.

A low ohm primary coil, is indeed capable of storing big power, as Terry's picture flash implies, but, with big electrical system drain, too.  However, if the voltage is clamped to existing spark gap levels, the current goes way up, and you get EDM effects or electrode erosion.  "Modern" EI systems use very large spark gaps and Iridium spark electrodes to provide extended spark plug life.  Further, "modern" EI such as coil on plug systems don't even store energy in the coil.  It is simply used as a voltage magnifier, that's why they are so physically small.

The Gerex was the only CD offering that I knew about, for the SOHC4, and they were (are) rare and costly then and now.  The payback period was so long as to make the product mostly out of reach at 3-4 times the cost of the cheapest Dyna-s.
That's another reason why the Dyna became popular, cheapest of the expensive flashy bits.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Bailgang

  • Scott
  • Old Timer
  • ******
  • Posts: 2,708
  • Indiana
Re: Thoughts about points
« Reply #166 on: September 27, 2017, 03:38:44 PM »
Long time ago my old man and I were witness to the sales pitch like tt scorns.

Man in a sales tent with an old v8 luxury car was selling coil power booster gadgets.
Of course he'd memorized the usual sales pitch "power, performance, economy"

But he went on to the "bigger better spark" display.  Had a little setup to show everyone what a spark would do to a piece of paper.  With and without his little gadget.  Stock part lit the paper on fire.  The gadget changed the spark and it burned a clean hole right through.  (Don't ask me to explain the science there.)

But the running motor test.  Without the gadget, it was a runner.  Little sluggish even.  Carbureted v8 yay. He'd start pulling plug wires off.  1 wire, motor started limpin.  2 wires, shut down.
With the gadget, motor ran with a bit more pep.  Then he pulled plug wires, 1, 2, 3 - motor still running.  On 5 cylinders.

My dad was an old school mechanic and he used to say that he'd never ever be fooled by a sales tent salesman in regards to anything automotive that is until he got suckered into a demonstration that seemed very similar to what you described many years ago. It was a gizmo that went in between the distributor cap and coil wire and supposedly would boost the output of the coil and the salesman had a very convincing sales pitch and demonstration because he was selling them like crazy and my dad bought one. He promptly put it on his 72 Ford F150 only to find out it didn't make the truck run any better in fact it lost 1 mpg in fuel mileage with that gizmo installed so off it came and my dad ultimately admitted he got fooled. I eventually found out that all that gizmo did was put a gap between the coil wire and the distributor cap which made the coil work harder to produce a spark and the reason it seemed so convincing on the demonstration engine supposedly had something to do with a smaller than normal sparkplug gap on all the plugs on the demo engine, maybe TT can understand this and explain. Essentially that gizmo was nothing more than a scam.








Scott


71 cb350 twin
77 cb750 F2
83 gl1100 Interstate

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,046
Re: Thoughts about points
« Reply #167 on: September 27, 2017, 04:28:08 PM »
Its amazing and not unusual to feel a difference after opening the wallet and installing a new goodie.
 I mean you really want it to work. 
 My big WTF moment....
 I sold my amen chopper, but kept the motor, my Andrews  coils went with it.
 Later put motor in stock frame, and not having the Andrews coils, I ran stock. And I thought it won't run as crisp.
To my surprise,  it did not feel different. Then I thought well maybe it will suffer at high rpm. I would shift at  11,000 or 11, 500 rpm .. ran clean..  so I was thinking WTF just happened here..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

AirCanuck

  • Guest
Re: Thoughts about points
« Reply #168 on: September 27, 2017, 09:23:05 PM »

electronic is set and forget and makes a nice fat blue spark but if it fails you're done, and it can overheat.
 

Carry a spare points plate in your breakdown kit. you do have a breakdown kit don't you?

I have only ever had one ignition trigger failure while riding a motorcycle, it was on points and it was because my points cover had been mangled so it was open and I got caught in a rain storm. Wet points don't fire. wasn't the points fault, I had just had an accident with the bike and I hadn't sourced a new points cover yet.

If you do something wrong installing them or maintaining them both have the ability to make you walk. years ago I accidentally deleted a resistor wire installing a hot coil in my GTO and I burned through a set of points in record time (GM points distributors use 8 volts, the resistor wire knocks it down from 12v). I switched to a petronix electronic ignition and an MSD digital 6 box only to have the msd box go bad in 2015 (at least I got 17 years of service out of it).

The only thing I personally object to is people waxing poetic about points like it is some kind of special man and machine magical bond. It's a set of clappers that makes spark.

As a new rider, and a first time bike owner, I do NOT have a break down kit (as I literally haven't ridden my bike - see my other posts - it lives at the mechanics it seems).  What do you recommend

AirCanuck

  • Guest
Re: Thoughts about points
« Reply #169 on: September 27, 2017, 09:26:29 PM »
electronic is set and forget and makes a nice fat blue spark but if it fails you're done, and it can overheat.

The "fat blue spark" is certainly a visual feast.  OOO - AAHH.   And quite attractive to those who are easily amused with shinny things.  But, it is not solely the result of replacing points with a transistor switch.  The coils are fed with 12V in either case.
The spark needs other components to make spark, like coils for example, and the actual color of the spark is dependent on the composition/ particle contamination of the atmosphere around the plasma channel that has formed.  How do you think that neon signs can emit different colors when fed an identical electrical charge?

The step up ratio of the coils (remember, that is also part of the ignition system?)  determines how much the 12v can be multiplied to a firing voltage.
The actual voltage attained is determined by how big a gap that is jumped.  Larger gaps need a higher initial voltage to bridge the gap.

A half inch gap jumped outside the combustion chamber, is fricking meaningless to what happens inside a running engine with spark gaps of .025 of an inch. 

To make yourself visually satisfied, you can put 3 ohm or less coils on a points trigger system and get that very same fat blue spark (outside the combustion chamber) that is irrationally idolized by many.

No one here, has actually relayed information about how a "fat Blue Spark" has any translation to HP or MPG improvement in a stock bike, only that it "feels" almost as impressive as it is visually appealing.  There is no science in these anecdotal reports.  And science has proven that humans are irrationally convinced that their purchases do what they want rather than what they actually provide.  It's a self reinforcement human trait.  And one reason why anecdotal reports are so famously unreliable.

If it's louder, its faster.  No need to actually measure it.  If I believe the bike is faster, then it feels like it, too.  It's what I expect and want.  That is what the "spark picture" is selling.  Further, "since I purchased it, if everyone else does too, it justifies my cash outlay".  (More human base psychology).

Picture of a "fat Blue Spark" is just eyewash.  If you are superficial enough to be swayed by such flashy images, you deserve to have your wallet further depleted.

The "electronic ignition" buzzwords are just a convenient marketing type label misapplied to a single ignition component.
Adding one or two transistors to replace point contacts, in no way approaches the modern vehicle equivalent to state of the art electronic ignition systems.  Such comparisons are disigenuous at best.

If you want to feed the greed of suppliers intent on extracting as much as they can from you, go ahead.
Also, if you are inept or unwilling to properly set a points system up to have the same HP and mileage as your friendly money splurger, go ahead.
Just don't feel you HAVE to buy an "electronic ignition" component, because that's what you need to be popular or be in with the "in crowd".
Your SOHC4 will run fine with the point system Honda provided.  All mine do.

I still maintain that the Dyna-S is an unworthy power hog design.  I'm glad I didn't buy it when seriously tempted in the 80's.

If you are irresistibly attracted to shinny things this should keep you occupied for hours.   ;D

Cheers,

I actually grabbed a timing light recently because I WANT to learn how to work with point ignition... I'm not leaning towards electric by any means.  I was just doing my best to summarize the two sides of this discussion, which largely seem to be anecdotal

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 16,375
  • Bike almost back to the 70's 2015
Re: Thoughts about points
« Reply #170 on: September 27, 2017, 09:38:16 PM »
More ignition facts and experience to fill this thread with? This will be a future dwell of wisdom and practical hints how to....
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,802
Re: Thoughts about points
« Reply #171 on: September 28, 2017, 01:09:36 AM »
...I eventually found out that all that gizmo did was put a gap between the coil wire and the distributor cap which made the coil work harder to produce a spark and the reason it seemed so convincing on the demonstration engine supposedly had something to do with a smaller than normal sparkplug gap on all the plugs on the demo engine, maybe TT can understand this and explain. Essentially that gizmo was nothing more than a scam.
Lots of marketing techniques borrow from the magician's tool kit.  Slight of hand and misdirection, for example.

For analysis, I'll use a points model, but a transistor switch/gate behaves similarly.
When the points close (or transistor on) the coil recieves power and stores it.
When the points open, the stored energy field's lines of flux colapses. The coil secondary windings are arranged physically within these lines of flux.  As the lines of flux collapse, they cross the secondary wires and induce a voltage.  This voltage rises (with the flux line crossings) in the secondary circuit which include the spark gaps of the spark plugs.  When the voltage attains enough voltage to form a plasma channel between the electrodes, spark happens.  The plasma channel behaves as a short circuit and requires much less voltage to maintain the channel.  But, the short circuit also means that the coil can't build up any more voltage potential, as it is drained off too fast by the short circuit at the plug electrodes.  This is why I maintain that the spark voltage in the SOHC4 is determined by the spark gap(s).  In fact, it is the sum of all the spark gaps, wherever they occur in the secondary circuit.  Increase the gap distance and the coils must develop more voltage to form the plasma channels in all the gaps in the secondary circuit. This is one reason why spark plug caps that measure open, can still fire the spark plugs.  There is almost always enough margin in the ignition system design to allow more than required spark voltage.  The stock coils are no exception.
So, adding a device in the spark plug lead pathway that presents a bigger gap to jump, increases the voltage needed to jump all those gaps and form plasma channels in each one.
There are always trade offs.  Working the coils harder, of course, increases their heat build up.  On hot days they can overheat and damage the insulation on their internal windings.  Further, at high RPM, they can demand more recharge time between firing events than is available, meaning they can't quite reach a voltage high enough to make plasma channels in all the gaps present.  Further still, if the system voltage is too low (think starter motor drainloads) there may not be enough power to store in the coil to allow the larger gap sum to form plasma channels.

Hope this helps,

Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Geeto67

  • A grumpy
  • Old Timer
  • ******
  • Posts: 2,822
Re: Thoughts about points
« Reply #172 on: September 28, 2017, 07:00:36 AM »

As a new rider, and a first time bike owner, I do NOT have a break down kit (as I literally haven't ridden my bike - see my other posts - it lives at the mechanics it seems).  What do you recommend

Start with better versions of what's in the honda tool kit (except the plug wrench - the honda plug wrench works pretty well and takes up minimal space). If you are wondering what's in a honda tool kit you can find that here:
https://www.cmsnl.com/honda-cb750-four-k5-1975-usa_model483/partslist/F++29.html#results

Honda Tool Kit substitutions
- 10mm and 14mm wrench: I replaced mine with a stubby gear rachet with an open crecent on one end
- philips head screwdrivers: I replaced the honda kit ones with 3 Hozan JIS screwdrivers in similar sizes
- Pliers: replaced with a Leatherman wave
- I kept the honda plug wrench, the 26mm eye wrench, the handle for the eye wrench, and the 45mm spanner. I didn't keep the lever since the screwdrivers have handles.

Added to the breakdown kit:
- Used but functional points plate, small square of sandpaper, and a book of matches in a ziploc bag.
- small coil of safety wire
- Small coil of electrical wire 18 gauge stranded wire
- folding knife. The leatherman has one as well but it's harder to use. I found a really flat one that's just a blade for cheap
- extra glass fuses in all sizes. At least two of each. I also have a screw that is the same size and length as a glass fuse and while I don't recommend it because it melts your fuse box, it will get you home.
- small square of folded tin foil
- needle nose vice grips
- folding allen key set in a holder that can be-disassembled.
- spare spark plug
- electrical tape
- tire gauge.
- small tube (1/2 oz) of super lube grease
- 12mm and 13mm stubby gear wrench
- half a dozen zip ties in various sizes.

On my bike keys as a "keychain":
- 8mm wrench
- thumbscrew philips head screwdriver
- thumbscrew flathead screwdriver
my local hardware store carried the key chain screwdrivers for cheap but here is what they look like:
https://www.ebay.com/i/281918660376?chn=ps&dispItem=1

non essential but it ended up on my bike anyway: A set of roll up sunglasses. Someone stole my helmet once and I had to ride home sans anything, crying all the way because of the wind. A buddy who did a lot of touring kept a pair of roll up sunglasses in a compartment in his goldwing and when he showed it to me I bought a pair. It's basically a film canister sized thing on a lanyard and fortunately I have never had to use it to ride home but I have used it once or twice as actual sunglasses when I forgot mine.
https://www.amazon.com/SportEYZ-Roll-Up-Sunglasses/dp/B01KYXDPXQ

I used to keep all this stuff in a strap on tool bag, but then someone walked away with it and honestly, it was a really nice hand tooled one a friend had made an I was madder to lose the bag than the tools. The next one I had was made out of a small square purse I found at a thrift store but someone cut that off the bike as well. So now I just keep all the tools and stuff stashed around the bike. for instance I keep the coil of electrical wire, the flat knife, the fuses and the aluminum foil in the paper's pocket under the seat. I keep the reg/insurance in a stick on pocket attached inside the side cover (I get those cellphone stick on card holders all the time from work for free so I figure I should put them to work). most everything else fits under the seat except for the things I keep on my key chain.


Keep In mind I have been riding for 25+ years so a lot of this came to me over time as I needed it or wished I had it and put it on the bike next time. If you wanted to "short cut", a friend of mine picked up this on closeout at iron pony and it isn't as fancy as what I have but it has a lot of the basics and a lot more than the honda kit:
http://www.ironpony.com/ipd/pi.asp/ImageName/490904EE1mOpen.jpg/Brand/WindZone/c2/Garage-and-Shop/c3/Tools/c1/ATV-Products/KitKey2/Essential-Metric-Tool-Kit

although I would still replace the plug wrench with an 18mm for the cb750.

There used to be a guy on this forum that sold a really nice tool roll for the cb750, complete with JIS screwdrivers.I forget his name and I haven't seen him around lately, but try searching. He sold the original frame kit too and carried the better quality (and now harder to get) Vessel JIS screwdriver sets.

I should add that this is only on my main rider 1975 cb750. It was a bike I rode almost daily into manhattan for years so it needed the most stuff. For my 2006 ducati, I don't carry anything more than the factory tool kit because anything that goes wrong with that bike is not fixable roadside. I carry almost no electrical stuff on my 1974 Ironhead HD because it runs a magneto so anything wrong with that is probably not fixable roadside, and anything electrical not wrong with it isn't important enough to worry about. The rest of the bike can be fixed with rocks and roadside debris so....

Always carry a cell phone. Always. I installed a cigarette lighter and carry phone charger in my cb750. In fact I charged my phone with it while I was out for a two hour night ride last friday night. I have a ram mount for my cell phone on the bars as well as a garmin GPS mount. none of this is essential but I like it. Why the garmin and not just use the phone for directions? I don't want to run the phone battery down and I don't want to be constantly charging the phone while riding. I also want it free to do other things.

Oddly, I am not a fix a flat roadside person. I've done it which is how I know I never want to do it again. If I was going cross country, maybe I would carry irons and a tube patch kit and spare tube, but otherwise not interested. Call AAA.
« Last Edit: September 28, 2017, 07:20:35 AM by Geeto67 »
Maintenance Matters Most

Offline Geeto67

  • A grumpy
  • Old Timer
  • ******
  • Posts: 2,822
Re: Thoughts about points
« Reply #173 on: September 28, 2017, 11:50:29 AM »
Christ’s sake, you’ll need a damn support vehicle to carry all that crap! Just carry a cell phone and a snack. Enjoy the snack while tow vehicle arrives and fix it at home.

Nope. It all fits on the bike and doesn't look any different from stock. It sounds like a lot, but it's all small stuff. I used some of it Saturday because the accel coils on the bike came free of their mounting and shorted out on the tank, shutting the bike down in traffic. the safety wire and zip ties got me home. I can't remember the last time the bike was in the back of a truck or trailer but it probably was 2004 when I had an accident on it and went to the hospital.

Actually I think the points plate isn't on it at the moment because I took it off to test the ignition system on my '75 cb750F when the Martek 440 wasn't firing. It turns out the coils were bad and I reinstalled the martek but didn't put the points back on the bike. When they are on there, they are zip tied to a frame rail under the airbox.  Since the bike is partially apart in my garage to remount the coils and make new plug wires, I should probably re-attach it.

Maintenance Matters Most

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 16,375
  • Bike almost back to the 70's 2015
Re: Thoughts about points
« Reply #174 on: September 28, 2017, 12:37:33 PM »
My bike has: Honda std tool set (best plug tool) + 3 allen keys (M5, M6, M8) + extra auto relays with fuses + small screwdriver for my carbs (horrible place for idle screw).
No problem in tool compartment and beside battery. My K6 have got a lower battery to get more space, Hondaman ign module is placed on top of it. 11Ah works fine with same size as std size except lower height.

I missed a bulb for rear light yesterday. I did not check it before riding to a nearby bike club's last meet for this year. 1:st time for years I rode in darkness and I missed the rear light. I had to activate brake....
Better bulbs need no extra. I'll replace it with Philips long life 21/5w I have been too lazy to replace the old one with.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967