Topic: Thoughts about points

[TwoTired]

Kitchen knives are deadly weapons.  Screwdrivers are deadly weapons.  Hammers are deadly weapons.  Autos are deadly weapons.  Motorcycles are deadly weapons.  A bottle of gas with a wick in it is a deadly weapon.
Mix bleach and ammonia from nearly any grocery store and you have a very deadly weapon.  According to the TSA, box cutters are deadly weapons.
So now we mustn't be allowed to discuss any deadly weapons?  No more freedom of speech?

Guns are tools and nothing more.  Seldom do you need a tool until you do.  Who are you to tell me I don't need one.  What ivory tower do you speak from?

More talk of guns is fine with me.  Education is a good thing, especially when it comes to powerful tools.  The more you know, the safer you can be.  The less you know, well that is just ignorance.  And words from the ignorant are far worse than talk about guns.

A government that does not trust guns in the hands of its citizens is not a government to be trusted.  That is a ruling government placing itself above the rights and needs of it's citizens.

And mealy mouthed nincompoops with emaciating agendas have no right or the intelligence to tell me what I need.  If you think otherwise, there are plenty of places in America that are more interested in exploiting the people than serving their actual needs...like education, for example.  Just move to the areas that have the strictest gun laws and ignore the high crime stats for the area...happily.

What's the old adage?  Keep the people fat dumb and happy and you can rule for eternity.  And misinformation is just another way of keeping the people dumb.

The anti gun agenda is evil in its conclusion.  It only serves to force subservience.
Lynch mobs proved that the majority is not always right.  Similarly vogue for the time.

This country was founded placing individual rights above all else.  Innocent until proven guilty.  Most other counties added selected individual rights as an afterthought.

I tend not to listen to those indoctrinated in countries outside the US.  Your rules and in many cases sensibilites just don't apply here in this culture.  I have no problem with you staying where you are and living under the rules you cherish.  If I thought your ways were better, I'd move there.

I'd rather live here.  Leave me alone with your propaganda.

[Lostboy Steve]

And if it weren’t for all those wild guys with their 1911s and M1s, your butt would be speaking Deutsch 

Are you really that old? How can we ever thank you? BTW... I speak Dutch and German and French and English and Spanish. Besides, I wouldn't go that route if I were you. FYI, it's widely acknowledged that the Soviet Union and it's army made the biggest offer by far in WOII: 10.700.000 deads (military) and another 11.900.000 civilians but, hey, that doesn't make a good holywood film, now does it? BTW, did they ever teach you anything on those numbers when you were in highschool? Oh, btw, when the liberation started (finally) my father and grandpa were still encarcerated for their work in the resistance. What do you think, are they excused? Shall we leave it here or do you maybe wanna discuss those wild guys with their 1911s and M1s in 'Nam? I dont know about you but I suggest we leave it here.

So you don't think armed Jews would have had a better chance evading or defending against the ss? That is naive of you.


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[BomberMann650]

Deltarider,
Your experience with sohc is greatly appreciated by me and your contributions to this board are immense. HOWEVER, I find your choice of avatars to be offensive as well as the video that you reccommend as being funny. I do not think it is appropriate. Generally, Americans would not think of offending any one from another country. We respect others choices and individualism here. Uour poitics are just that...they are our politics
Dickl

Delta and I don't always see things eye to eye.
But I find his choice in avatars to be a rather pointed commentary on the state of the world.
That said, I'm not offended.  Disturbed maybe.  But not offended.

[madmtnmotors]

I was not aware that dual point ignitions carried such global political implications... 

[Terry in Australia]

And if it weren’t for all those wild guys with their 1911s and M1s, your butt would be speaking Deutsch 

Are you really that old? How can we ever thank you? BTW... I speak Dutch and German and French and English and Spanish. Besides, I wouldn't go that route if I were you. FYI, it's widely acknowledged that the Soviet Union and it's army made the biggest offer by far in WOII: 10.700.000 deads (military) and another 11.900.000 civilians but, hey, that doesn't make a good holywood film, now does it? BTW, did they ever teach you anything on those numbers when you were in highschool? Oh, btw, when the liberation started (finally) my father and grandpa were still encarcerated for their work in the resistance. What do you think, are they excused? Shall we leave it here or do you maybe wanna discuss those wild guys with their 1911s and M1s in 'Nam? I dont know about you but I suggest we leave it here.

So you don't think armed Jews would have had a better chance evading or defending against the ss? That is naive of you.


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Did you ever wonder why the Jews stayed in Germany when it was clear that they were in immense danger? Google SS St Louis (also known as "The ship of the damned") when you have a quiet moment, it's a story that we should all be ashamed of.

[PeWe]

.......
My old Borg-Warner racing (high performance) dwell meter shows my 750 at 44-46 degrees between 0.012" and 0.014" gap. That's where I usually run mine.

OK, that is the 0.3-0.35mm area.
Minimum gap will load ign coils more, right?
But need to be adjusted when points wear with reduced gap.

I'll see if the bike will run different with slightly less gap.

Checked ignition today
My cheap auto multimeter with dwell function showed 24 degrees at 8 cyl setting. I had set the points to 0.35mm (0.01378") the old way with feeler gauge.

I have had problems at low rpms lately that I have blamed the open exhaust and cam combo.
During ignition setting with strobo lamp: Engine idled really smooth when the 3 point plate screws were loosened, erratic idle when tighten them. I could finally tighten them with OK idle after some attempts where F should align case mark correctly too.
I guess I witness the problem with point plate orientation that some use shims to center the plate properly.
I'm rather sure that this problem can be seen as carb problem and  a throttle synch will not help.

Another project then, add shims for correct plate alignment. If wrong, ignition is not possible to set correctly.
Erratic idle, rattling chains  which feels like typical CB750.... when I know better, typical wrong centered point plate. My point plate is a TEC.

I see this sometimes, too. When I have seen it, I found that the 'foot' of one of the points sets was hitting the points cam at an angle, so only one corner of the 'foot' was pushing open the points. I fixed it by slightly bending the pivot shaft on the points (had to take them all apart for this, slow process!).

Thanks for your observations Mark, I'll check the points and how they have contact with the cam. I have new  spare TEC points if needed.

Just install an EI Per and get rid of that mechanical crap. Sure, it might be more expensive than points or fail after 30 or 40 years like Danny's Martek did, but by then you'll be too old to remember how much you paid for it!

I have an almost new Dyna-S on the shelf.
Points are a part of the CB750 despite it's not seen until the cover is removed. The points must have got a shock of a kind at last teardown of the engine or later when I shifted advancer, a point or both not properly aligned and need to be adjusted.
An EI might not have survived a similar event

[Terry in Australia]

I have an almost new Dyna-S on the shelf.
Points are a part of the CB750 despite it's not seen until the cover is removed. The points must have got a shock of a kind at last teardown of the engine or later when I shifted advancer, a point or both not properly aligned and need to be adjusted.
An EI might not have survived a similar event

Yeah mate, points came standard on a CB750, but from memory, you've got a 1000cc engine with a billet block, ported and polished head, bigger valves, heavy duty studs, rods, lightened and balanced crank, heavy duty primary chains, Mikuni carbs, and probably lots more, so why, with all of those other non-original parts fitted, is it important for you to keep bumming around with points?
 
Your points are giving you problems because they might have received a shock at the last rebuild? Here's a pic of my K2 that I bought back in 2010, Ken, the PO, crashed it at over 60 MPH, destroying the forks, the NOS speedo and tach, ripping open the fuel tank and oil tank, and as you can see, it came down very hard on the points cover. The Dyna S ignition behind that mangled points cover still worked perfectly..............

TerrysCanberratrip13Mar20101 by Terry Prendergast, on Flickr   

[DickL]

Anyone using the Chevy 57 to 74 points with the condensor attached that has the allen wrench dwell adjustment screw?

[ekpent]

Anyone using the Chevy 57 to 74 points with the condensor attached that has the allen wrench dwell adjustment screw?

  If your talking about the Maxi-Dwell set-up I have a couple new still in the packages but have never tried one yet. As well as fitting on a CB750 they also fit the Kaw 900 z series.

[Terry in Australia]

Do they come with a backing plate Eric? The Z1 backing plate is bigger than on a CB750. Cheers, Terry.

[ekpent]

Do they come with a backing plate Eric? The Z1 backing plate is bigger than on a CB750. Cheers, Terry.

I will have to look at the package again Terry. It just seems from memory that both bikes,models were listed on the package but the memory may have an error also. Will take a pic. Speaking of the back plate that was a weak spot supposedly on the Maxi-Dwell. Instead of being made of some thicker steel it was made from a thinner type of aluminum or other alloy and could supposedly change with the heat throwing things off a bit.
Edit- Think your correct Terry as I see the Kaw is listed as a different model then the Honda 4. Have to check out my package though and my memory also-    Here is some official hype as to why you NEED this unit. Pays for itself in the first 3 minutes     http://www.xpipe.org/pdf/M-Dsalesinfo.pdf

[Deltarider]

Of all the countries that I've travelled, only two states had reached that level of civilisation where one is allowed to carry a gun in public: the USA and... Yemen.
  This is what happened a couple of weeks ago. The room was full with friends and beer as we were to watch a footballmatch on television. First there was this newsprogram. It was about the flooding in Houston. A reporter interviewed a man in front of what once had been his house and now was nothing but a pile of rubble. He aged 35, was in shorts and, both hands firmly on his sides, looked very manly. Right below his left hand his gun. He didn't seem sad at all. This is what the Texan answered the reporter: "Look, I've saved my kids, saved my wife, saved the dogs, saved my guns... " He stopped and shrugged his shoulders. I will not forget that picture. Why the gun? Behind his back there was nothing to defend, ab-so-lute-ly nothing. Why the gun?
  I asked a question: "Am I the only one that... etc". And I pointed at the remarkable difference in reception when you openly show (and praise) guns, which I consider bad taste, in comparison with images shown of a couple making love. And I still think this difference is worth giving it a thought.
  I finished highschool in the 70s. Our teacher English in 4th grade happened to be an American. From the works of Shakespeare, he would jump to our modern time every now and then and inform us on life in the US. I remember distinctly Mr Cloony (or Clooney) was of the opinion that the freedom to carry a gun in public was a misinterpretation of the Second Amendment. The right to keep and bear arms in his view had been ripped out of context as was never ment to allow just every Tom, Dick or Harry to walk around with guns.
OK, guys, enough of this. I like you to smile again, so here is reporter and candidate gunslinger Sacha Baron Cohen. Enjoy:

[754]

The Maxi Dwell uses solid state condensors, very small and yellow I  believe.  About 7/16 or so square,  stacked together they took up Very little space . Plus they had the  built in timing light, very small switch.
 The base was aluminum, much lighter. Be easy to make now, just waterjet them.

[Glenn Stauffer]

Hey everyone.  This is an informative technical thread about points and electronic ignitions that threatens to be derailed by a debate on gun ownership.  The gun posts will be removed from this thread shortly.  In the meantime, please keep the discussion to the topic.

[Geeto67]

I choosed both, Points AND Electronic ignition. Hondaman module
It got condensors (capacitors) today too. Were delivered with the point plate, NOS TEC
I have used it without most of the time. I have had some minor misfires now and then at higher rpm that might be the result of no condensors.

I checked ignition setting today with dwell meter and strobe lamp. Still spot on since  almost one week back!! I was sure that the setting should go bad when I moved point plate a little counterclockwise and then clockwise from my setting to see if dyno result will change. (It did not like more advance at higher rpm, a little bit later OK, but no big deal.
I'll have to adjust again this winter when I lift cam to re-torque the head just  for sure. Maybe I let another cam play around for a while...

Set ignition is a must for me anyway since I remove the ignition when timing the cam, degree wheel is mounted on the advancer.

Alright guys.  I'm biting the bullet of embarrassment.  What is dwell on this system?

The 'dwell' angle is the amount of time the points are closed in one revolution, measured in degrees.
But, cheap dwell meters will yield different readings from those often published here. If the dwell meter you have in use can first be calibrated to points-closed reading (zeroed) and then run, it will give an actual dwell. Most aren't that good, today, being just pulse-width measurement estimation gadgets. I have on old racing meter which IS accurate, but for the sake of not starting another 'oil thread'-like argument, I won't published what the real dwell numbers are from these bikes.
Instead, set the gap and timing to be spot-on for YOUR bike with YOUR dwell meter, and then remember that value, instead.

Hey Hondaman,

Can you walk me through the process of checking both Dwell and Tach on the CB750. It has to be like 15 years since I have done it with a dwell meter, I found my old dwell meter the other day and for the life of me I couldn't remember how to use it on a motorcycle.

I actually just want to check tachometer accuracy more than point dwell but this thread could use some tech instructions in it.

[Lostboy Steve]

Of all the countries that I've travelled, only two states had reached that level of civilisation where one is allowed to carry a gun in public: the USA and... Yemen.
  This is what happened a couple of weeks ago. The room was full with friends and beer as we were to watch a footballmatch on television. First there was this newsprogram. It was about the flooding in Houston. A reporter interviewed a man in front of what once had been his house and now was nothing but a pile of rubble. He aged 35, was in shorts and, both hands firmly on his sides, looked very manly. Right below his left hand his gun. He didn't seem sad at all. This is what the Texan answered the reporter: "Look, I've saved my kids, saved my wife, saved the dogs, saved my guns... " He stopped and shrugged his shoulders. I will not forget that picture. Why the gun? Behind his back there was nothing to defend, ab-so-lute-ly nothing. Why the gun?
  I asked a question: "Am I the only one that... etc". And I pointed at the remarkable difference in reception when you openly show (and praise) guns, which I consider bad taste, in comparison with images shown of a couple making love. And I still think this difference is worth giving it a thought.
  I finished highschool in the 70s. Our teacher English in 4th grade happened to be an American. From the works of Shakespeare, he would jump to our modern time every now and then and inform us on life in the US. I remember distinctly Mr Cloony (or Clooney) was of the opinion that the freedom to carry a gun in public was a misinterpretation of the Second Amendment. The right to keep and bear arms in his view had been ripped out of context as was never ment to allow just every Tom, Dick or Harry to walk around with guns.
OK, guys, enough of this. I like you to smile again, so here is reporter and candidate gunslinger Sacha Baron Cohen. Enjoy:

Why the gun? Looters, that's why. Like stated previously by others, you don't live here, you have no idea why we cherish our 2nd amendment.


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[BomberMann650]

The admin has spoken.  Don't make him go get his "enforcer" 

[PeWe]

I have an almost new Dyna-S on the shelf.
Points are a part of the CB750 despite it's not seen until the cover is removed. The points must have got a shock of a kind at last teardown of the engine or later when I shifted advancer, a point or both not properly aligned and need to be adjusted.
An EI might not have survived a similar event

Yeah mate, points came standard on a CB750, but from memory, you've got a 1000cc engine with a billet block, ported and polished head, bigger valves, heavy duty studs, rods, lightened and balanced crank, heavy duty primary chains, Mikuni carbs, and probably lots more, so why, with all of those other non-original parts fitted, is it important for you to keep bumming around with points?
 
Your points are giving you problems because they might have received a shock at the last rebuild? Here's a pic of my K2 that I bought back in 2010, Ken, the PO, crashed it at over 60 MPH, destroying the forks, the NOS speedo and tach, ripping open the fuel tank and oil tank, and as you can see, it came down very hard on the points cover. The Dyna S ignition behind that mangled points cover still worked perfectly..............

TerrysCanberratrip13Mar20101 by Terry Prendergast, on Flickr   

Hi Terry,
1004,725cc (71.25mm pistons), cam too, DP315 with a high overlap that might cause additional adjustments. DP327 cam in and an RC sidewinder exhaust on and I'ts ready for the strip! The CR might be too low though, only 10.5:1. Dilute the fuel with nitro might compensate...
Threads like this makes this forum really fun! Different tech talk and ideas based on hundreds of years in combined experiences of bad and good.

I believe that the points can work as good as Dyna-S ignition and be more robust (no electronics that might not withstand overcharging that happen during a few minutes now and then).
I have Dyna 5 ohm coils on the bike that must be an upgrade compared with stock.

I can test the Dyna-S to compare but has not time now since I have OK ignition and dyno time soon.

It is a challenge for me to make the bike to run perfect with points as I'm sure it will I can replace the TEC condensors with other capacitors of correct value, smaller size.

I have mostly had carb jetting work behind. I have done dyno times this year to find the correct tuning and has found most of the settings for street and cruising speed. Carbs had no recommendations and I had to change all, pilots, needles and mains. Important to find correct order of the jetting to avoid change again.

I'll check again on Wednesday this week to verify the last correction of float setting on carb 1-2 that caused lean at WOT. Full power and A/F ratio measured in each exhaust with no baffles/diffusers. I balanced the carbs wrong earlier, all 4 at same clear tube setting. These carbs seems to work different so I change back the adjustment I did earlier causing lean on carb 1,2.

Then another hp/torque run with baffles/diffusers in since this will be the setup I'll use which work rather fine right now.

I understand racing guys that use Dyna 2000 with adjustable advance curves.
Maxi dwell might be something since it will most likely work fine with Hondaman ignition module.

*** More Point Hi-Tec *****
I checked the points today to verify Hondaman's observation of how the points bakelite fot contact cam on adv unit. Must be parallel and not bent point hitting the cam with the corner of the fot first. Both points operated correctly when I exercised them manually, contact to cam parallel and electrical contact points looked correct too. Not like old cheap points almost hitting sideways.
The point plate however, is in the good position since last ign setting.

I'll check that the advancer unit has no dirt between the unit and crank and that the point plate is clean with smooth surface where it has contact with cases which must be good too.
These last checkpoints must be valid for a Dyna-S too, right? How it is centered is not that sensitive as for a Point plate?

I have to find the old thread were TwoTired described the importance of a properly centered point plate, shims might be needed.

[PeWe]

I choosed both, Points AND Electronic ignition. Hondaman module
It got condensors (capacitors) today too. Were delivered with the point plate, NOS TEC
I have used it without most of the time. I have had some minor misfires now and then at higher rpm that might be the result of no condensors.

I checked ignition setting today with dwell meter and strobe lamp. Still spot on since  almost one week back!! I was sure that the setting should go bad when I moved point plate a little counterclockwise and then clockwise from my setting to see if dyno result will change. (It did not like more advance at higher rpm, a little bit later OK, but no big deal.
I'll have to adjust again this winter when I lift cam to re-torque the head just  for sure. Maybe I let another cam play around for a while...

Set ignition is a must for me anyway since I remove the ignition when timing the cam, degree wheel is mounted on the advancer.

Alright guys.  I'm biting the bullet of embarrassment.  What is dwell on this system?

The 'dwell' angle is the amount of time the points are closed in one revolution, measured in degrees.
But, cheap dwell meters will yield different readings from those often published here. If the dwell meter you have in use can first be calibrated to points-closed reading (zeroed) and then run, it will give an actual dwell. Most aren't that good, today, being just pulse-width measurement estimation gadgets. I have on old racing meter which IS accurate, but for the sake of not starting another 'oil thread'-like argument, I won't published what the real dwell numbers are from these bikes.
Instead, set the gap and timing to be spot-on for YOUR bike with YOUR dwell meter, and then remember that value, instead.

Hey Hondaman,

Can you walk me through the process of checking both Dwell and Tach on the CB750. It has to be like 15 years since I have done it with a dwell meter, I found my old dwell meter the other day and for the life of me I couldn't remember how to use it on a motorcycle.

I actually just want to check tachometer accuracy more than point dwell but this thread could use some tech instructions in it.

Dwell is very easy, done when bike engine is running. MRieck started a thread where I filled in with photos.
One thing I did different last time and better, smaller gap, 24 degrees at 8 cyl setting 0.35mm gap according to my dwell meter
http://forums.sohc4.net/index.php/topic,147444.0.html

Do the basic ignition first
http://www.hondachopper.com/garage/carb_info/timing/Static_and_Strobe_Timing.pdf

Advancer unit springs can be something too, Hondaman has written about it which I read and could make my engine to run better.
http://forums.sohc4.net/index.php?topic=131339.0

[Geeto67]

thanks PeWe

[HondaMan]

I choosed both, Points AND Electronic ignition. Hondaman module
It got condensors (capacitors) today too. Were delivered with the point plate, NOS TEC
I have used it without most of the time. I have had some minor misfires now and then at higher rpm that might be the result of no condensors.

I checked ignition setting today with dwell meter and strobe lamp. Still spot on since  almost one week back!! I was sure that the setting should go bad when I moved point plate a little counterclockwise and then clockwise from my setting to see if dyno result will change. (It did not like more advance at higher rpm, a little bit later OK, but no big deal.
I'll have to adjust again this winter when I lift cam to re-torque the head just  for sure. Maybe I let another cam play around for a while...

Set ignition is a must for me anyway since I remove the ignition when timing the cam, degree wheel is mounted on the advancer.

Alright guys.  I'm biting the bullet of embarrassment.  What is dwell on this system?

The 'dwell' angle is the amount of time the points are closed in one revolution, measured in degrees.
But, cheap dwell meters will yield different readings from those often published here. If the dwell meter you have in use can first be calibrated to points-closed reading (zeroed) and then run, it will give an actual dwell. Most aren't that good, today, being just pulse-width measurement estimation gadgets. I have on old racing meter which IS accurate, but for the sake of not starting another 'oil thread'-like argument, I won't published what the real dwell numbers are from these bikes.
Instead, set the gap and timing to be spot-on for YOUR bike with YOUR dwell meter, and then remember that value, instead.

Hey Hondaman,

Can you walk me through the process of checking both Dwell and Tach on the CB750. It has to be like 15 years since I have done it with a dwell meter, I found my old dwell meter the other day and for the life of me I couldn't remember how to use it on a motorcycle.

I actually just want to check tachometer accuracy more than point dwell but this thread could use some tech instructions in it.

It has to start with correctly-gapped points. Set them at 0.014" precisely, for starters. Then, short the leads of the dwell meter (if it has a CAL function) and adjust for zero dwell. Then hook up to the points and run the bike: the dwell number that it shows will then be correct for the meter in use. You can then take that number to any bike that has the same coils on it.

If the coils are different ohms, this process must be done for that bike, and that dwell number recorded. The inexpensive dwell meters all presume a 12.0 volt power to the coil of 1.8 ohms (which is the old standard coil's resistance wire for cars in the USA), and these bikes are either 4.6, 4.4, 4.3 3.0, or maybe 5.0 ohms, so the number can change from one bike to the next. The better meters have the ZERO function, which drops this calculation out of the equation. For this reason, meters like my (very) old Borg-Warner will read the same dwell for 0.014" on any of the SOHC4 bikes with the TEC, Hitachi, of ND spark advancers, which all used the same dwell angle. But, this number will not match the number from a typical multimeter-with-dwell function, which is just an averaging circuit that reads out the root-mean-square-voltage value in the pulse.

[fireman1073]

 In the 70s I had a 1974 Honda 750 and I converted from points to electronic ignition, seem to have better throttle response and easier starting. Later  I purchased at 77 Kawasaki KZ 1000 and also converted it to electronic ignition for the same reasons, of course this doesn't take into account my poor wrenching skills  at the time,I was young
 I never experienced any issues  with either points or the electronic ignition, I just noticed better performance with the electronic ignition
 At the time it seemed state of the art and was considered  A great upgrade
fast forward many years and I am surprised that people migrate toward using the point set up  with one exception when the points have an issue it's easier to correct than the electronic gizmo . I do find Hondaman's ignition  interesting and will use one on my next build

Steve

[PeWe]

I choosed both, Points AND Electronic ignition. Hondaman module
It got condensors (capacitors) today too. Were delivered with the point plate, NOS TEC
I have used it without most of the time. I have had some minor misfires now and then at higher rpm that might be the result of no condensors.

I checked ignition setting today with dwell meter and strobe lamp. Still spot on since  almost one week back!! I was sure that the setting should go bad when I moved point plate a little counterclockwise and then clockwise from my setting to see if dyno result will change. (It did not like more advance at higher rpm, a little bit later OK, but no big deal.
I'll have to adjust again this winter when I lift cam to re-torque the head just  for sure. Maybe I let another cam play around for a while...

Set ignition is a must for me anyway since I remove the ignition when timing the cam, degree wheel is mounted on the advancer.

Alright guys.  I'm biting the bullet of embarrassment.  What is dwell on this system?

The 'dwell' angle is the amount of time the points are closed in one revolution, measured in degrees.
But, cheap dwell meters will yield different readings from those often published here. If the dwell meter you have in use can first be calibrated to points-closed reading (zeroed) and then run, it will give an actual dwell. Most aren't that good, today, being just pulse-width measurement estimation gadgets. I have on old racing meter which IS accurate, but for the sake of not starting another 'oil thread'-like argument, I won't published what the real dwell numbers are from these bikes.
Instead, set the gap and timing to be spot-on for YOUR bike with YOUR dwell meter, and then remember that value, instead.

Hey Hondaman,

Can you walk me through the process of checking both Dwell and Tach on the CB750. It has to be like 15 years since I have done it with a dwell meter, I found my old dwell meter the other day and for the life of me I couldn't remember how to use it on a motorcycle.

I actually just want to check tachometer accuracy more than point dwell but this thread could use some tech instructions in it.

It has to start with correctly-gapped points. Set them at 0.014" precisely, for starters. Then, short the leads of the dwell meter (if it has a CAL function) and adjust for zero dwell. Then hook up to the points and run the bike: the dwell number that it shows will then be correct for the meter in use. You can then take that number to any bike that has the same coils on it.

If the coils are different ohms, this process must be done for that bike, and that dwell number recorded. The inexpensive dwell meters all presume a 12.0 volt power to the coil of 1.8 ohms (which is the old standard coil's resistance wire for cars in the USA), and these bikes are either 4.6, 4.4, 4.3 3.0, or maybe 5.0 ohms, so the number can change from one bike to the next. The better meters have the ZERO function, which drops this calculation out of the equation. For this reason, meters like my (very) old Borg-Warner will read the same dwell for 0.014" on any of the SOHC4 bikes with the TEC, Hitachi, of ND spark advancers, which all used the same dwell angle. But, this number will not match the number from a typical multimeter-with-dwell function, which is just an averaging circuit that reads out the root-mean-square-voltage value in the pulse.

There is one good thing with the cheap Dwell meter, both points can be set equally when engine idles. Start with a gap your recommend, then verify both with dwell function and adjust if needed.
There are a many new cheap multimeters for sale in the 25USD area, then used vintage meters in unknown status. The function might not change due to aging components

[PeWe]

I'm not a native English language person but I know the expression "there's no point in" (doing something)....
It must therefore be meaningless without points !

EDIT: I found TwoTired's description of not centered point plate in the FAQ section
http://forums.sohc4.net/index.php/topic,5752.msg47539.html#msg47539

[Terry in Australia]

In the 70s I had a 1974 Honda 750 and I converted from points to electronic ignition, seem to have better throttle response and easier starting. Later  I purchased at 77 Kawasaki KZ 1000 and also converted it to electronic ignition for the same reasons, of course this doesn't take into account my poor wrenching skills  at the time,I was young
 I never experienced any issues  with either points or the electronic ignition, I just noticed better performance with the electronic ignition
 At the time it seemed state of the art and was considered  A great upgrade
fast forward many years and I am surprised that people migrate toward using the point set up  with one exception when the points have an issue it's easier to correct than the electronic gizmo . I do find Hondaman's ignition  interesting and will use one on my next build

Steve

Yeah mate, I'm looking forward to installing the Dyna III ignition that I bought from Chewbacca here a few weeks ago, in my CB750K2. I bought one from another member (Mike Beltrami) back in the 1990's and I installed it on my first CB750F2. The difference between it and the new genuine OEM points plate and coils that were in it (I was trouble shooting, the bike would run fine, then run like #$%* as soon as it rained, turned out to be a faulty ignition switch) was like night and day, with the Dyna it had a big fat blue spark like the one in the pic I've posted here a couple of times, it'd start as soon as I touched the button, and it felt more powerful, with much better throttle response.

Like you say, "back in the day" they were considered a performance improvement, and while ignition amplifiers were available from a couple of companies and cheap to buy, a "proper" electronic ignition was a better option. I often wonder what power loss, if any, is caused by the parasitic nature of spring loaded ignition points continually rubbing against the points cam? I know that Mark said that just by removing the 8 small bolts in the newer cam towers that prevent the rocker shafts from turning is good for a couple of horsepower, so I can't help but wonder?

Over here it costs around 300 bucks to do a couple of dyno runs so I won't be doing any side by side testing any time soon, but I'll just spend half of that and continue to buy electronic ignitions and call it good! Cheers, Terry.        

DSCN0659 by Terry Prendergast, on Flickr