Topic: CB Digital Ignition

[Bamboozler]

The weather is shaping up and the riding weather is here.  I’m finally getting motivated to write about the side project adventure that I’ve been kicking around with the help of a few friends.  I’ve been fortunate to get to know some talented individuals whose expertise lie in hardware and firmware design. So naturally I’ve made it a point to bother and annoy them into helping create a digital ignition for CB and other points platforms.  If all goes well I wish to offer it to anyone that would find it worth while, which I believe from a feature set vs price standpoint it will be when all is said and done.  I'm sure it will not be for everyone, the few non microprocessor based iggys being sold are excellent units and suit/satisfy most very well.  This will guy will hopefully satisfy a gap between the base ignitions and high end versions for those wanting a bit more flavor without breaking the bank.

The idea to pursue an ignition was picked up when fabbing my turbo CB, thinking that a digital iggy for controlling spark timing while in boost would be a benefit to have.  Seeing the steep price for what was available, the idea to offer an equivalent and less expensive iggy that was bomb proof was attractive and fun project.  It was a year+ ago that I made the development platform (motor, magnet rotor, power supply, magnet sensor) for Eric the firmware coder to play with in order to start writing code.  But the idea drifted a bit until fall/winter this last year when I finally took the time to write up some specification for him to code toward.  After the specs were loosely written down, my friend Eugene crafted the first rev of hardware schematics, and earlier this year I ordered and assembled 5 proto/test units.  The project has been a great learning experience to say the least!  Coming from an electronic tech background I’ve been most fortunate to be able to be the glue between it all.

For a general description the iggy is a magnetic hall effect pickup based microprocessor controlled ignition.  It has its own CNCed rotor and hall sensor PCB plate that replaces the stock CB’s points and advancer unit.  Controlling the advance/retard of the spark gives quite a bit of options and flexibility/control.  Currently the iggy uses two hall sensors and one magnet, but that is being changed for a single bipolar latching hall and two magnets to help reduce setup error offset (will touch on this later).  The main board has three rotary switches for setting parameters, two LEDs: one for 'power on' and one for setting TDC, as well as a handful of I/O wires.  The feature set is most equivalent to a Dyna 2000 if it were to be compared to another with some unique features of its own.

The current feature list is loosely set and can be added to or subtracted.  There will for sure be one (knock on wood) more hardware spin and then hopefully will be considered a releasable candidate.  I will say that I’d be interested in hearing any suggestion that would make this guy better.  If anyone has any comments for better or worse I’d appreciate the feed back.  It’s still quite early in the project’s development and as noted, features can be added and removed.  What features would you like to see or have access to? 

The iggy hasn’t ran a bike yet, just a set of plugs on the bench.  I just received the first prototype CNC rotor and I’m excited to be able to start testing with the bike soon.  I am in the process of getting the bike out of hibernation and waiting for a new release of firmware that incorporates an improved acceleration algorithm.

I’ll pick apart the specs and shed additional detail and test info in future updates to this thread when time permits.  Below is the “loose” spec list that is currently built into the rev 1 hardware and is subject to change.  (Sorry for the wall of text in this post).






Current feature set, Release Candidate 1 code base  (sorry for the few ported formatting oopsies)

    * Low RPM power savings with equivalent spark energy vs stock points (edited to remove better)
          o ~70% less current draw from stock coils at 1200RPM w/ equivalent spark energy
          o ~50% less current draw from stock coils at 2000RPM w/ equivalent spark energy
          o ~22% less current draw from stock coils at 3000RPM w/ equivalent spark energy
          o Matches or exceeds stock coil current draw from 3800RPM to red-line (yet to be set in stone: how much to exceed stock spark energy vs consume too much current)
          o Optimal for additional battery loads (hot coils, pumps, lights) in town stop and go traffic riding conditions
    * Spark Timing control rotary (2500RPM to red line)
          o Advance: 2-16 degrees in 2 degree increments
          o Retard: 2-14 degrees in 2 degree increments
          o OFF
          o from 1000 to 2500 (full advance) spark event advances from 10 degrees to 35 degrees; stock CB750 profile (or CB550 ect..)
    * RPM limit control rotary
          o 6000 - 13,000 RPM limit in 500 RPM increments
          o OFF
    * Shift Light Indicator or RPM activated trigger control rotary
          o 6000 - 13,000 RPM set points in 500 RPM increments
          o OFF
          o Able to sink 2.5A (3A max) of accessory current (shift light, relay, small pump, ect)
    * Boost/Vacuum switch enabled timing control
          o Advance or retard timing based on trigger events from a external pressure or vacuum switch
          o Allows stock timing profile until pressure/vacuum switch event. After switch event timing retards or advances to  the     setting dialed on the timing set rotary switch.
          o Pull timing with boosted applications (Boost Pressure Switch)
          o Advance timing for greater motor efficiency/fuel economy  with high vacuum steady RPM cruising (VOES Switch)
    * Digital tachometer output
          o 5V output
          o outputs 1:1 true RPM. 
    * Security disable
          o Grounding the security disable control wire disables spark output
    * Timing light (strobe) for dynamic timing verification
          o Connector on hall sensor board allows for a LED timing light accessory to be plugged in
          o timing light drive circuit build into main board (yet to be implemented on current Rev 1 hardware)
    * With ignition on, coils stop drawing current when no crank rotations are detected after a certain time period



Current Electrical Features

    * Robust design with reliability as #1 underlying goal
          o Tantalum (dry) capacitors in place of Electrolytic (wet) capacitors
          o IGBT coil current control
          o Reverse battery protection
          o External input/output wires clamp protected from environmentally noisy EMI energy to prevent damage to sensitive on board electronics
          o External input/output wires terminated directly to main circuit board (no connectors)
          o All PCB components specified for a minimum of 105C/221F, processor rated at 140C/284F
          o PCB encapsulated in hybrid epoxy elastomer, ultimate in weather proofing
                + Excellent thermal cycling performance
                + Supple 37ShoreA hardness
                + Exceptional encapsulating shield
          o Sealed Rotary DIP switches
          o EMI Shielded cable connects Main board to hall sensor rotor board
    * Crank position data provided by dual magnetic Hall sensor (changing to 1 hall 2 magnets)
    * 5-3ohm compliant, possibly 2.2-1.5ohm coils (needs test coils and heat testing)
    * Low current draw
    * 20MHz processor operating speed
    * Power On LED
    * Cylinders 1/4 Top Dead Center indicator LED
    * Small enclosure foot print (approximately 3"x2"x0.6" w/ two 0.5" mounting tabs)

[Hasenkopf]

woah.......

[Pinhead]

VERY NICE!

You've probably already looked into it and decided it'd be too complicated to implement... But how about vacuum advance/retard using a GM MAP sensor?

And how about selectable dwell control (in ms) to create a "constant energy" ignition system? This would allow people to run cheap and more widely available automotive coils that produce a MUCH stronger spark.

[Bamboozler]

Doug, great ideas you have!   I can’t say I’ve thought to accommodate a GM MAP sensor directly on the main board. I think you would have to in order to set it's switch point and control how you want it to trigger.  A GM turbo 3 bar MAP sensor would work well in that it gives your both pos/neg pressure, really like that idea!


As of now there are two wires that control the timing retard/advance, one wire (enable) that needs to be grounded to tell the micro that there is a switch in place and a second wire (activate) which is grounded by said external boost/vacuum switch when activated to tell the micro to add/subtract the dialed in + or – degrees of timing.  Without the enable wire grounded (no switch being used) the micro looks at what degrees of timing + or – is dialed up on the rotary and simply applies it when the full timing RPM is reached (from 2500 RPM to redline). If you do have the enable wire grounded (switch installed), until the switch activates and grounds the trigger wire the stock timing is used for full advance RPMs of 2500+ (35 degrees BTDC in the CB750s case).


In the ignition’s current config a Hobbs switch or VOES switch would work off the shelf because they have an adjustable trigger point built in with a set screw.  Unfortunately you have to choose your poison, play with advance, or retard (NA or boosted), but not both. With the GM MAP you’d have to add circuitry on the iggy or with an external circuit to instruct where within the 0-5V output level you want the switch point, and also to tell the micro how to trigger (dropping or rising into the set point for vacuum/boost respectively).  But with basic/crude controls (rotary switch) it would be difficult to setup a more complex scheme than a single switch event. This is where a simple USB to PC cable and PC configuration app comes in to save the day. 


Regarding the selectable dwell control, I haven’t tested any other coils outside of the stock coil pack, Dyna 5 ohm, and Dyna 3 ohm.  What coils do you have in mind?  I’d be willing to run a current profile on them and see what they look like on an oscilloscope. It’s quite possible to add adjustable dwell, the only down fall is that one of the rotary’s would have to be scarified.  If any I guess it would be the shift light or RPM window activate rotary.  It’s in a way novelty, but could serve useful in certain applications.  Wish I could add another rotary but the available I/Os on the mirco are nearly full. 


Thanks again, I appreciate the input!

[Retro Rocket]

Subscribed

[750]

Me too

[MasterChief750]

very very very interested in this. tried the pamco and it works but not what i want.

[pamcopete]

Very interesting product and one that will find a market here. What is your projected selling price for the system? What is the operating voltage range? When will it be available?

[brandEn]

subscribed!

[Bamboozler]

Hey Pete, The operating voltage is one thing that I forgot to add to the specs.  The micro runs at 3.3v and is clamped on the high end at around 22v, so I'd say a healthy operating voltage would be 5-20v.  It should be well low enough to allow the coils to fire before the voltage becomes too low to allow the plugs to fire the air/fuel reliably.

We'll see how fast the changes can be implemented.  There's a 5-6 week lead time on a small order of rotors and the main and rotor PCB need to be spun again.  I'm hoping somewhere around June/July.  But as with every hopeful estimate, tag on a x2+.  I'm hoping to stick to the early summer date.  This will firm up and time goes on.

Pricing is not firm yet, still have to finalize the bill of material.  I’m going to loosely say ~$200 give or take and it’s looking promising that it could come in on the underside of that figure.  The biggest question will be assembly methods and quotes that need to be requested yet.  This is for main board, rotor board, black anodized laser or machine etched CNCed rotor, and small timing light LED accessory (if its determined to packaged that way).

Just want to note that this is the best current guess based on what I know at the moment.

[Flying J]

Your work continues to amaze me. Subscribed and in line. 

[TwoTired]

Quick comment on your specs.

You need to specify an operating environment.  (It is not the same as the part maximums.)

The power consumed or sink'd inside the box will add to the temperature rise inside.  How will that exit the box?
This heat will add to the whatever the box is operating within.
(Consider, if the box were a perfect insulator, the temp would just rise and rise until failure, even if it was just a watt or 10 degrees/minute.)


Probably needs a humidity (non-condensing) and altitude spec, as well  (these effect heat dissipation radiation).

To protect yourself from returns you will need to specify input limits that can damage the unit. (Like spark V on the power supply) 
Yes, you have to assume the worst in the hands of the public.  They'll be mounting directly to the head pipe and run full bore through the desert unless you tell them that's not acceptable and not covered under warranty.

- Mechanical shock and vibration spec, operating/non-operating. 

[articblue]

Neat. Looking forward to this.

[HondaMan]

Quick comment on your specs.

You need to specify an operating environment.  (It is not the same as the part maximums.)

The power consumed or sink'd inside the box will add to the temperature rise inside.  How will that exit the box?
This heat will add to the whatever the box is operating within.
(Consider, if the box were a perfect insulator, the temp would just rise and rise until failure, even if it was just a watt or 10 degrees/minute.)


Probably needs a humidity (non-condensing) and altitude spec, as well  (these effect heat dissipation radiation).

To protect yourself from returns you will need to specify input limits that can damage the unit. (Like spark V on the power supply) 
Yes, you have to assume the worst in the hands of the public.  They'll be mounting directly to the head pipe and run full bore through the desert unless you tell them that's not acceptable and not covered under warranty.

- Mechanical shock and vibration spec, operating/non-operating. 

Good, TT.
Also: consider that many of the bikes are stored to -40 degrees, as well. Surface-mount boards may struggle with this.

Quick comment on your specs.

You need to specify an operating environment.  (It is not the same as the part maximums.)

The power consumed or sink'd inside the box will add to the temperature rise inside.  How will that exit the box?
This heat will add to the whatever the box is operating within.
(Consider, if the box were a perfect insulator, the temp would just rise and rise until failure, even if it was just a watt or 10 degrees/minute.)


Probably needs a humidity (non-condensing) and altitude spec, as well  (these effect heat dissipation radiation).

To protect yourself from returns you will need to specify input limits that can damage the unit. (Like spark V on the power supply) 
Yes, you have to assume the worst in the hands of the public.  They'll be mounting directly to the head pipe and run full bore through the desert unless you tell them that's not acceptable and not covered under warranty.

- Mechanical shock and vibration spec, operating/non-operating. 

Good, TT! They will need all the similar suggestions they can muster, to make it successful.
A thought or two: many of the bikes are stored to -40 degrees. Surface-mounted components can struggle to be reliable with this cycle if the details are not closely watched.  Too many of these bikes get hit with a 20+ amp battery charger, then started, come Spring: study how this will impact your power situation. The inductance of the coils varies widely, and can cause IGBT or MOSFET devices to act unusually: ensure flyback OFF control to make sure the gate turns off, no matter what. This may require adding source resistance, which takes you back to TT's second comment about the heat.

A feature suggestion: in these waste-spark engines (Kawis, too), there may need to be a point to retard the timing a bit between 2 distinct RPM ranges. See the "Thoughts of Hondaman" post about 14k-16k RPM versions of the CB750 to understand the issues. This is a phenomenon known to some of the vintage racers and midget car riders, too.

Best of luck with it! Sounds like fun.

[Bamboozler]

Great point you make TwoTired and I appreciate the thoughts!  I would like to add that the specs are just a ballpark of the electrical based on spec sheets as noted.  Please don't take them for anything other than a quick reference of what's inside.

I'm fortunate to have access to an environmental chamber via my hardware friend (freon system for cold, humidity, and heat), an industrial shock vibration table, ESD gun, and a hipot tester and will be compiling numbers to create a more extensive real world specs and to see what exactly the unit can endure.   I hope within the next month I will be able to put together a more comprehensive list of operating parameters as you noted.  It's something that has been planned to be done before the second and final board spin.  The five proto units are intended to contribute to this testing.

The one thing that is of the highest importance is making sure this is a reliable unit.  Components have been selected to provide the best chance of survival in the extremes.  One of the greater concerns is just that, the ability for the unit to shed it's heat, especially when being encapsulated in potting compound and having a relatively small foot print for the IGBT in order to keep the unit's foot print small.  So far in free air with an ambient of 80F the IGBT heat sink pad normalized at around ~64C during maximum coil current draw when measured with a thermistor, which is promising .  But needs to be potted for the real testing to begin.  If something turns up to be marginal in performance it will be address before it will be released.  Last thing I would want to see is failures due to improper design.  Thanks for the notes regarding the assumption of worst case scenarios, an excellent reminder to keep in mind!

[Bamboozler]

Good, TT! They will need all the similar suggestions they can muster, to make it successful.

Just want to note again that I really appreciate the comment and helpful suggestions that both of you are providing.  This is the first adventure down a development path for me, and while there is quite a bit of experience that I have to seek from my friends who have been down this path many time themselves, the drive is coming from my corner.  Any different angles that can be brought forth to and have light shed on I will open with open arms. 

HM, thanks for your cold weather suggestions!  Gives some good ideas to test toward.  I'll be digging your thread suggestion up and look into that dual timing retard. Thanks again for the heads up!

[Bamboozler]

I'm just happy I wasn't asked to provide any radiated EMI or conducted emission test data... though the altitude data threw me, now I'm going to have to rent a hot air balloon and figure how to get the CB inside the basket for collecting data....    (Just kinding TwoTired, all in fun   I've read plenty of TT threads and if there's a hole he will find it.  But as a result, the conversations and knowledge that ensues benefits everyone who follows along for the ride, which is appreciated.

When posting info, data, test results from a project you can guaranteed a good majority of views are looking at it with a critical eye to knock a hole in what you've reported; human nature.  But as long as you are willing to be open minded it can help to improve what you're working on.

Thanks for the luck Pete!

[Bamboozler]

I would like to briefly touch on the fundamental operation of the ignition and current savings in the low RPM that comes with it.  I think this is a real benefit to those that have extra loads on their bikes such as hotter coils, extra lights, pumps and so on.  I myself am interested in this feature with the two extra pumps that I’m running (fuel and oil scavenge). 
 
The stock points based ignition operates with roughly a 190 degree charge or dwell, and a 170 degree discharge (model dependent).  This fixed charge time lends itself to a bit of inefficiency during the lower RPMs.  For an example, at an idle of 1250 RPMs the time it takes the motor to make a single revolution is 48mS. Of this 48mS, 52.7% of the revolution (190 degrees, (190/360))  is dedicated to charging the coils, or roughly 25.3mS.  The next thing that needs to be looked at is how long do the coils need to be charged to reach full charge.
 
With the help of an oscilloscope and current measuring circuit 3 common coils where bench tested for their current changing characteristic; the stock coil pack, Dyna 5 ohm, and Dyna 3 ohm.  If the pictures are not legible, the time between the two dotted lines marking the start and stop is ~13.0-13.3mS (full charge); or 2mS per division.  The typical discharge waveform is thrown in at the end.
 

Stock CB750 coil (4.5 ohm)


Dyna 5 ohm coil (black)


Dyna 3 ohm coil (green)



characteristic discharge curve thrown in for good measure
 
The Oscope screen captures shows it take roughly ~13.3mS to achieve nearly full 99.5% charge, each coil being a slight bit different.  For the current rev the digital iggy we choose to allow a dwell of 8.2mS which falls within the 95% of full charge.  Slightly down on spark energy vs 13.3mS's 99.5%, but for the most part equivalent.  This value is flexible and can be changed, but 8.2mS it is for now.  As Doug point out earlier in this thread, this value is what could be tied to a rotary to provide a selectable dwell value.
 
Back to the stock points ignition at 1250 RPMs, it sits charging for ~25.3mS vs the digital iggy that is charging for 8.2mS.  That being said, ((25.3mS – 8.2mS) / 25.3) * 100 = ~68% current savings with nearly the equivalent spark energy.  I think 8.2mS dwell is reasonable compromise of current savings vs spark energy.  By around 3600 RPM the saving is dried up and gone because one revolution of the motor takes ~16.5mS and 52.7% of that 16.5mS is given to the charge dwell, or 8.2mS; at this point the stock dwell matches the digital iggy’s 8.2mS for charge time.  From this point on the digital ignition maintains the stock points 190°/170° dwell until redline. *note below
 
The first chart below shows the current draw of the whole system with the digital iggy using a stock points equivalent 190°/170°charge/discharge profile (to replicate the stock points ignition's current profile). The second chart shows the current draw of the whole system utilizing a 8.2mS charge dwell until 3600 RPM while maintaining near equivalent spark energy (~95%) as in the first chart. The supply voltage was set to 13.6v and current measured with a both a digital and analog meters and spark plugs where firing. There’s quite a bit of current savings with a near (95%) equivalent spark.  This would be a nice benefit when sitting and a stop light or while doing a lot of in city stop and go riding with a power thirsty CB.


Current (Amps) vs. RPM

digital ignition flashed with a replicated stock points 190°/170° dwell

Current (Amps) vs. RPM

digital ignition flashed w/RC1; 8.2mS dwell until 3600 RPM and stock points 190°/170° dwell from 3600 RPM to redline.  Equivalent spark energy as the first graph, with a lot less current draw.


*As of now the post 3600 RPM dwell will remain the stock 190°/170°.  However there will be some evaluation to see if optimizing this charge/discharge spilt has any benefit.  Possibly extending the 8.2mS further and or creating an optimize charge/discharge algorithm.

More when time permits...

[HondaMan]

Nice work on those charts! 
It shows well the issues we've learned to live with (or struggle with) on the various coils.

Your traces look a lot like the ones I saw when we developed the unit that everyone now calls the Hondaman Ignition (it is really called the "S3" for "Solid State Sparks", but no one remembers that now  ). That's a good idea, shortening the dwell in slow speeds for saving a little energy for other thingies on the bike. The alternator-challenged 550 comes to mind...

I might suggest the use of the ND X22ES-U sparkplug for the 500/550 engines with this gizmo when you get it working, as those particular plugs already improve on those bike's in-city spark, but with the truncated dwell they would allow at least a spark equivalent to the D7EA fire at full dwell and full 12 volt coil supply. What we have seen on those bikes is the need for something that can make a more ionized spark at 10 volts drive to the coils after about 15 minutes or more in heavy traffic, where the front running lights and typical halogen headlight lower the system voltage a little too much (this has always been their Achilles Heel, since they were new).

My long-winded thought about this is: the stock Honda coils on these bikes (turns ratio 400:1) charge a bit faster than the 750 coils you are showing here. So, for those riders who would like to implement this new controller with the stock Honda coils, using the X24ES-U plugs, the result could be the same spark voltage and duration as is found at 3500+ RPM, which is where the resonance of the 400:1 coil first reaches above the 63% peak spark voltage range, when used with stock condensors.

I used a form of analog trickery to accomplish this boost on the S3, which results in better cold-fire spark performance for the 1975 and later "lean-burn" versions of these bikes, and collaterally improves on the low-speed performance for the 500/550. 

[pamcopete]

bamboozler,

So, if I read it right, your new system will not offer any benefit above 3600 RPM? No increase in HP or torque?

I was a little surprised that you did not include sub 1 Ohm coils or coil on plug or split the timing and get rid of the wasted spark system with its 40% energy penalty on the positive plug wire.

Basically, you could design a system for a coil per cylinder with four IGBT drivers driving four coils all of which would produce a negative voltage instead of the positive / negative voltage of a dual output coil. The coils would, of course, only fire on the compression stroke.

Such a system would double the time between pulses while cutting the duty cycle in half. You could  continue your dwell angle algorithm up to 7200 RPM, increasing HP and torque along the way. If you used a sub 1 Ohm coil, you could continue all the way to red line, any red line.

The trick is to find a way to determine when a piston is on its compression stroke. I suppose there are various schemes to determine which stroke a piston is on. The simplest would be a vacuum sensor that would tell you when the cylinder is on the intake stroke and go from there.

I think that you mentioned that you may include vacuum sensors anyway to assist with the advance curve management and allow a greater advance, so the vacuum sensors would be in place anyway.

Splitting the cylinders and eliminating the wasted spark and the 40% penalty also means that the effectiveness of exotic spark plugs, such as the Iridium plug, would be doubled. With a wasted spark system, only one of the two cylinders truly benefits from the Iridium plug, or Platinum or whatever precious metal is used.
This increase in efficiency would be reflected in better mileage and more power.

[Pinhead]

Regarding the selectable dwell control, I haven’t tested any other coils outside of the stock coil pack, Dyna 5 ohm, and Dyna 3 ohm.  What coils do you have in mind?  I’d be willing to run a current profile on them and see what they look like on an oscilloscope. It’s quite possible to add adjustable dwell, the only down fall is that one of the rotary’s would have to be scarified.  If any I guess it would be the shift light or RPM window activate rotary.  It’s in a way novelty, but could serve useful in certain applications.  Wish I could add another rotary but the available I/Os on the mirco are nearly full. 


Thanks again, I appreciate the input!

Wells Manufacturing Corp. makes them. The model is the C849 coil. It fits most Chevy Cavaliers from the early 1980's to 2005, along with many other GM vehicles. The primary DC resistance is between .4 ohm and .5 ohm, and has an average inductance near 2.8 mH. This means it reaches 5.8 amps in approximately 1.3 to 1.5 msec.

Looking at your current profiles and comparing to the stock coils, however, it seems that this coil may be outside of the 500/550's charging capabilities. BUT since it only draws that current in a 1.4ms time-frame, the alternator may be able to keep up. I know my CB650 has no problems with it, though it also has about double the alternator output...

[Bamboozler]

Hey HM, that again for your notes.  I hope that the shorted low RPM dwell will give the fragile 500/550s a bit more fight again the battery run down.  Interesting to note regarding the ND plug, I hadn’t come across your findings regarding them but find it interesting to say the least. I will do a bit of research in your finding, thanks for the heads up!

Pete, whatcha talkin’ about, just crank up the timing advance dial and you’ll have a boat load more torque and HP, much more than any wiz bang spark can give ya… .  It’s obvious that you’ve been thinking about this before.  The very topic has been discussed when brain storming techniques to implement. 

The underlying reason to keep it simple is cost and simplicity.  I initially wanted to push the idea of config file based PC programmable spark widget that could do everything under the sun.  But after discussing back and forth it was decided to keep it simple, see how a ‘base’ entry flavor would work, and if it seemed to be worth the efforts, push forth on a ‘do everything’ model.  It works well for a base unit to keep the bill of material cost down for those not wanting to drop a ton of coin and gives something to look forward to on a more feature filled deluxe version for the enthusiast. 

I do acknowledge benefit of tech that you’re speaking of. You pointed out the benefits of such a system very well.

Doug, that current does rocket up right quick.. One thing I wonder is the balance of the low resistance/low inductance coils vs the high res. higher L like the stock bikes use.  The low res./L charges faster but stores less energy resulting in a shorter duration spark (verses the high res/L coils) but higher voltage spark.  In a way is like debating the CDI vs Inductive ignition systems (short high voltage spark vs longer lower voltage spark). Interested in taking a look that those coils.  You are very much correct that they are cheap!!

[pamcopete]

bamboozler,

OK. So, basically your are going to build an electronic replacement for points that does not have any advantage over points above 3600 RPM but has a few cute features at idle that will save some power and people are going to pay $200 + for this product?

1. The motorcycle engine spends most of its adult life above 3600 RPM.
Your product has no advantage above 3600 RPM.
2. The product you are describing can be made with an off the shelf Motorola MC79075 chip, no programing required.
3. You are going to base the design on a 5 Ohm coil and not take advantage of the much greater output of even a 2.5 Ohm coil or an HEI sub1 Ohm coil to solve the dwell angle problem at higher RPM's.
4. You have no interest in a coil per plug system that would solve the positive plug voltage penalty of a wasted spark system, the dwell angle at higher RPM problem and the excessive duty cycle associated with a wasted spark system because it would add $1.50 to the cost of hardware.
5. It also appears that you intend to introduce the product at a basic level, have a few hundred people buy it, and then hit them with an upgraded product soon after.

This product will not be any better than points, Honda Mans transistor driver,  PAMCO, or Dynas product, but it will cost more than any of them.

Like I said before...good luck!

[Flying J]

Are you competing with twotired for "idea killer" now?    I see you erased your previous comment.

[pamcopete]

Are you competing with twotired for "idea killer" now?    I see you erased your previous comment.

I did not erase my earlier comment. The management did.

I am not killing an idea here. bamboozler has a great opportunity to build a system that solves all of the problems of a wasted spark system that would add $1.50 to his bill of material. Without a solve for the inefficiencies of the wasted spark system, his system is not better than points above 3600 RPM, as he himself freely admits.