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Brand new CDI for Hondamatic CB400A/CM400A/CM450A

Maraakate

Maraakate

Veteran Member
Joined
Jun 7, 2022
Total Posts
2,579
Total likes
693
Location
Lancaster, PA, USA
Hello,

I've been working on reverse engineering the Hondamatic CDI for the CB400A, CM400A, CM450A bikes. It's now been successfully road tested for more than 3000+ miles in stop and go traffic, and highway. Over 20 sold.

Here is a video of the prototype running on my 79 CM400A:

CURRENT STATUS 09-23-2023:

Now available for order. 20 cases this time to keep up with demand!
Added product variation when ordering CDIs. It will now ask you if have the 1978 year. This is to let me know if you require the bullet connectors or 2-pin canon plug for the blue and white wires.

Winter time project sale. All CDIs are $100 off (sale price $200) until March 31. Get that bike running before spring!

Special 20% discount for VHT Forum Members. Use code 'VHTMembers' at checkout!
  • Total price is $300 shipped to the US. International customers please E-Mail me to discuss options. Current lead time is 2 weeks as each one is built individually by me and tested dynamically with an actual stator/rotor.
  • Kits are discontinued due to user error. If you can convince me that you're competent and understand there is zero warranty/support then send me a PM. I will only offer this for VHT members.

You can order the complete plug and play unit here. Other ordering options include my ebay store https://www.ebay.com/usr/eggmatorch, direct PM on VHT, or via E-Mail.

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I have had a few questions elsewhere as to why the cost is what it is. The metal case, which bolts up the same as the original is high quality and manufactured locally. It's even thicker gauge than the original and slightly taller to allow more room for the components, reducing stress on them.

I take no compromises on the quality of this unit. Each CDI is hand assembled by me, with high quality automotive rated components and Japanese Nichicon capacitors, just like the original. The harness uses high quality components from Matt over at Vintage Connections/Sparck Moto. This is not cheap junk, it will last as long as, if not longer, than the original unit. I personally use it on my own bike and wouldn't settle for anything less.
 

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Looking good there and finally we will have some help with A model CDI's with new parts instead of used and abused if even functional salvage parts.
 
Maraakate said:
Hello,

I've been working on reverse engineering the Hondamatic CDI for the CB400A, CM400A, CM450A bikes. I've successfully built some larger than original dimension prototypes and I am now sending off the shrunk PCB design to the manufacturer.

What's the degree of interest? Is anyone interested in purchasing one? They won't be ready for probably about a month or two as I will also have to work out the sheet metal work for the outer casing. But these will have brand new wires, connectors, etc. Current cost is unknown, but I'm anticipating somewhere around $80-$150.

I also plan to make them available as a kit with the bare PCB and components and you can solder it yourself and reuse your old harness and mount it however you like.

Here is a video of the prototype running on my 79 CM400A:
https://youtu.be/neOAnKUinyA

CURRENT STATUS 06-07-2022:


  • Ordered additional parts to make about 10 CDIs from Digikey. Parts shipped yesterday and will be here Thursday.
  • PCB layout with the reduced size to fit in the original size can sent to China, approved, and has shipped. Will be here Monday.
  • Working with an epoxy supplier on some additional questions about the use of this particular brand. I'd like to coat part of the inside of the metal can as well, let it cure, then put the PCB in and fill again. I want to make sure this epoxy can adhere to itself or if I have to do a different method.
  • Contacted Vintage Connections about getting Green with White tracer coloured wire (had to substitute Green with Yellow) and smaller gauge Green with Black tracer (they only had 14, which works, but is overkill and more difficult to work with for a simpler jumper in the harness). I also contacted them about possibly supplying me harnesses cut to size and ends crimped to save time on my end for an additional fee. I gave them measurements, etc. and they are looking into this.
  • Someone donated me an empty CDI can, waiting on that to show up so I can get proper dimensions and then map it in CAD software so I can send it off to get some quotes.

For those interested: I have 2 prototype PCBs remaining. They are larger than the original, about 3 inch by 3 inch. If you want the blank PCB and/or parts as a "kit" please let me know.
Click to expand...

Please check your PMs (private messages). Thanks
 
More parts arrived from DigiKey today, waiting on the new PCBs. In the meantime someone did want the larger prototype one built so I have built another one, tested it, and this one has a fresh harness I made. Works great, will be shipping tomorrow.

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NB: The through hole sizes for the harness are wrong on the prototype boards. It's been fixed in the new boards that arriving. Thus the solder blob bus I got going on on the backside for the harness. User was OK with this as they have a non-running bike and just want to get it running.
 
STATUS UPDATE 06-10-2022:

* DHL says revised PCBs will arrive this afternoon. Will solder up one for testing and confirm.
* Consulted with the epoxy supplier for my application. It will work, and set the way I am expecting it to. This is now ordered.
* Mixing cups and larger digital gram scale for weighing out the epoxy ordered, will be here tomorrow.
* Person who is donating me empty CDI casing is shipping today, should be here next week.
* Once arrived, a local friend who uses CAD will map it out as a 3D model for me to get quotes on sheet metal pricing.
 
Thanks for the progress updates. You won't have the strict corporate attitude here about making these available for owners like our members, all they're concerned with at that other forum is the money VS can make off their hostage members.
 
STATUS UPDATE 06-10-2022 PART 2:

* New, smaller boards arrived, soldered one up. It works.


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Just took it out on a 10 mile ride. Rode it kind of hard revving up "Lo/1" upto about 45-50mph then shifting to "Hi/2". Passed the test. Now we just gotta wait for the epoxy and getting the cases.

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In the meantime, if anyone wants the bare circuit board with the components and a harness total cost is $70 shipped USCON for that. PM me if you want one. Turn around time will be about a week as I have to order more parts for that.
 
Someone requested a video of the new PCB. It's more of the same, but for brevity here it is:

 
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STATUS UPDATE 06-13-2022:

* I made a Revision 5 of the PCB. It's the same size as Rev 4, but I have added two mounting holes for those who want a kit. TH1 has been moved down, and D1 has been moved over to allow TR1 to be bent down for clearance in the original cases. Just like the original PCB. I also optimized the spacing of TR2 so you don't have to bend the pins back as much to get it to fit. Otherwise, the board is the same. These boards will arrive in two weeks. Not a high priority as the Rev 4 boards will work just fine with the new cases.
* I have a friend who is good with AutoCAD and will make a 3D model of the original case over the course of this week. The height of the case will be extended by half an inch to compensate for Rev 4 boards, but also to allow a bit more room for epoxy. We have an inch and a half of room to play with before you get clearance issues with the tank.
* Supplies needed to prep surfaces for epoxy have arrived. Epoxy should be here on Wednesday or Thursday.
* I got rid of the zip tied case, found a waterproof plastic container that will barely fit the frame and tank and it's now my main CDI. Will move it to metal cases when they're ready.

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Thanks! Now, if only I can figure out what power darlington transistor was used for that change switch relay and we could find a supplier who can make QUALITY carb insulators then we'll be in business!

I haven't mentioned it here previously, but someone got in touch with me a partial schematic of the CDI and the change relay, with notes. I was able to make a perfboard version of the change switch relay box. The lights on the dash work, but the starter won't turn over as it must think it's in gear. I did a lot of measurments at the probe points between my homebrew version and the original and it's mostly the same except for two spots. Working with an EE friend who has been patient with my dumb questions to figure that part of it out. Mostly it comes down to we don't know what darlington transistor was used so the specs required to on/off that part of the circuit is unknown. But he's given me advice on how to figure it out myself and been doing some reading on some circuit theory that I haven't had to think about it in a very long time. No guarantees on the change switch relay stuff, but I am poking at it in my spare time and do intend to come up with the circuit for this as well one of these days.

If anyone has broken change switch relays I'd be very interesting in buying them from you to get apart to further work on the reverse engineering of this module. You can email me, [email protected] or send me a PM on the forums.
 
Agree with Jim, your work on this is great and will be very appreciated by the 400A owners who are smart enough to take advantage of it.
 
Thanks for the kind words, but I can't take all the credit. God bless whoever the man was on the Yahoo Group from twenty years ago and posted some minimal information about the capacitor value and the larger SCR. And thanks to the person who sent me additional broken boards with a partial schematic that I was finally able to merge notes and come up with something that worked.

I'm fortunate that I have a friend who has been hosting one of my websites for years. I got in touch with him this evening about setting up a separate domain with an ecommerce page in order to sell these. I think we're at a point now that I could sell at least the kit for people who want one. Current turn around time will be about 3 weeks.
 
This really is remarkable. I don't trust my skill with the bare circuit board but I'm definitely tracking this project for a future order. Thank you for tackling this, Maraakate.
 
Hi knauff,

Thanks for the kind words.

Plug and play units should be available in a month or so. I also plan on updating the ecommerce page today to add a fully assembled and tested kit as an option for someone who wants to the circuit board to mount in a custom case, but doesn't want to do the soldering work.
 
ancientdad said:
Thanks for the progress updates. You won't have the strict corporate attitude here about making these available for owners like our members, all they're concerned with at that other forum is the money VS can make off their hostage members.
Click to expand...

The "other" forum has been kind enough to send me a PM now that an e-commerce page is available saying that is now "time" to setup a vendor option with them. I looked it over and they want $50/mo for the privilege of announcing that my product exists on their forum. I did mention that I am just some guy making them on my workbench and if it is possible to continue updating the thread with status reports on the plug and play units and then locking the thread when this is done.

$50/mo is quite nuts. $50/yr might be reasonable. I would be sincerely surprised that I would be selling enough of these monthly to justify the $50/mo. Quite sad the state of affairs for revenue at the "other" forum.

Hopefully people over there can smarten up, find the thread here and join this forum and not deal with that level of silliness.
 
Too bad they can't search for it any more either. I have now noticed they have deleted the thread in it's entirety. So anyone who was asking questions can no longer receive help for me. Glad to see they're interested in helping riders keep these bikes running.
 
Maraakate said:
Too bad they can't search for it any more either. I have now noticed they have deleted the thread in it's entirety. So anyone who was asking questions can no longer receive help for me. Glad to see they're interested in helping riders keep these bikes running.
Click to expand...

Wow. It's one thing to be derelict in their duties in maintaining the board. Openly suppressing an idea that is clearly helpful to riders and fills a need is another. What a shameful mess corporate ownership has made of that board. You're in the right place now, I think.
 
I'm quite surprised by their pricing structure for advertising. If it was say... $5/mo for small, independent "vendors" such as myself then I would begrudgingly pay it. The price structure is clearly designed around large vendors that everyone knows such as 4into1 where they could afford such advertising.

Well either way, I guess it's over on the "other" forum. I do find it a real shame that the information there is now lost.

Their response to allowing the thread to continue with status updates only regarding the plug and play unit until it is complete:

"The free tier does not allow business promotion. I'm not the guy to negotiate with. You are using our population to promote your product. If you sell on eBay they will take a cut in return for access to their marketplace. Same here as I see it."

I countered with on ebay they only take a cut of the sales, and their pricing structure is not affordable to someone like me who is making a small run product and that it could be improved upon that small vendors could still pay something and that their site still generates costs to keep it running and users are informed and everyone can win. But, I won't hold my breath on that one. I'm not a large vendor who sells tires that ship the same day or sells thousands of aftermarket parts for practically every japanese bike made in 1968-1985.

Either way, silly and somewhat sad as that forum has been regurgitated across facebook and other places over the years as the place to go. But this is really the place to be.
 
Maraakate said:
Their response to allowing the thread to continue with status updates only regarding the plug and play unit until it is complete:

"The free tier does not allow business promotion. I'm not the guy to negotiate with. You are using our population to promote your product. If you sell on eBay they will take a cut in return for access to their marketplace. Same here as I see it."

Either way, silly and somewhat sad as that forum has been regurgitated across facebook and other places over the years as the place to go. But this is really the place to be.
Click to expand...

This is exactly why we left. Once we understood who the new owner really was it was obvious that they were not interested in maintaining a community atmosphere as it had been prior to the VS ownership and format change, during which they acted as if nothing would change only to completely ignore practically everything we said or asked to have changed or repaired.

The statement in bold above is absolutely laughable. The "population" they refer to was built by the founders of HT over most of a decade before VS even paid any attention to HT. It was built by positive daily interactions with individuals who came to HT for help with their bikes - not by buying the forum, rewriting the TOU and holding all their members hostage with no ability to discuss other forums where better help could be found since they don't give a crap about the members or the bikes, only the ad revenue that can be generated by the previous success of others.

You're completely fine here, and though it will take a few more years we have no doubt what the future holds. We've seen plenty of forums die at their hands, and eventually our significantly greater daily activity here will overshadow the longstanding search results that VS is living on for now (previously built by the core group of now-VHT members) as all the truly intelligent content and answers there slowly age out.
 
ancientdad said:
This is exactly why we left. Once we understood who the new owner really was it was obvious that they were not interested in maintaining a community atmosphere as it had been prior to the VS ownership and format change, during which they acted as if nothing would change only to completely ignore practically everything we said or asked to have changed or repaired.

The statement in bold above is absolutely laughable. The "population" they refer to was built by the founders of HT over most of a decade before VS even paid any attention to HT. It was built by positive daily interactions with individuals who came to HT for help with their bikes - not by buying the forum, rewriting the TOU and holding all their members hostage with no ability to discuss other forums where better help could be found since they don't give a crap about the members or the bikes, only the ad revenue that can be generated by the previous success of others.

You're completely fine here, and though it will take a few more years we have no doubt what the future holds. We've seen plenty of forums die at their hands, and eventually our significantly greater daily activity here will overshadow the longstanding search results that VS is living on for now (previously built by the core group of now-VHT members) as all the truly intelligent content and answers there slowly age out.
Click to expand...

You guys explained to me the situation over there and I have seen some of it for myself, but wow I was not expecting them to ramp up this quickly with how they chose to be with me.

I know it's no surprise to anybody here, but after I had what I thought was a decent conversation with their admin I told him my concerns and mentioned that I understand hosting costs money and security and updates (as I worked in IT for years) and for a forum of this size I understand. However, I think for small vendors the pricing is unrealistic and paying like $50/yr or something to still contribute to helping that site, advertising a part that YOUR users will benefit from still pays bills and everyone wins. After that I was referred to calling VS to complain about it, and it was mentioned that I was not the only small vendor who feels this way. Afterwards, I was banned for 24 hours from their forums.

I'm guessing I was banned from someone above the site admin, probably read his PMs and saw my discussion and didn't fit with their forum-for-profit ideals. A real shame that even a long time admin and moderator can't even be a reasonable person on their own site any more. But, I guess the money that they or someone received offsets that. :/
 
Maraakate said:
I'm guessing I was banned from someone above the site admin, probably read his PMs and saw my discussion and didn't fit with their forum-for-profit ideals. A real shame that even a long time admin and moderator can't even be a reasonable person on their own site any more. But, I guess the money that they or someone received offsets that. :/
Click to expand...

If I had to guess, it was probably the forum admin who banned you temporarily. He is NOT a longtime admin there, he was brought in by the corporate admin from another one of their sites (Honda Rebel forum) and his post totals are a complete lie as probably is his supposed CL350 project. Another VHT member "knows" him from the Rebel forum and was scolded not long after Keith the admin came to HT late last year for suggesting that HT wasn't doing very well and that there was a better place to get the information everyone there needs. It's a sordid tale of greed hidden behind the front of HT still being a "community" for the benefit of everyone. There are many horror stories on the internet about VS's forum takeovers, doesn't take much to find them and it validates what we know is their only motivation - money, of course. You can't even mention another forum (unless it's one VS owns, of course), especially VHT, without it being censored in both public posts AND private messages... yes, they go that far.
 
That's nuts. Yes, it was that guy. He seemed reasonable, but I guess unfortunately he has to look out for his interest. I don't know if they get compensated or if he got a payout when VS bought it out and if he doesn't comply then he can lose that. That's my guess, but I really have no idea.

Maybe it's been stated here or in a PM to you or Jim, but I originally did this project mainly for myself as I wanted a spare. But, yeah, it's nice to get paid a bit for your work and help other people out. There's plenty of Hondamatic's out there rotting in someones garage or leaning against a shed because of a bad CDI. And what I'm offering is all new components with modern designs as the quality of electronic components has increased significantly over the past fourty years. I'm aiming to keep it a price point where I still get compensated for my work, but you can still buy it at a reasonable price. The same or less than an unknown used fourty year old CDI that has no warranty whatsoever. It's offered in a kit form to satisfy the hackers who want to play around mounting it their own way (or swapping values to see if they can mod that curve) or people who just want to save some money. And then of course, sometime in the near future there will be a fully assembled, plug and play swap unit for people who just want to drive and not solder things up and think about mounting. I'm trying to make it as fair as possible, and I'm not intending this as something I'm going to quit my day job over.

With that said, I appreciate all the support on here. Once things start picking up with production in the upcoming month or so I intend to place a donation to you guys to help with hosting costs and to let you know that I appreciate letting me post here about all of the work that I've been doing on it.
 
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I don't know what to say other than none of this surprises me in the least. I didn't think they'd act this fast, figured the end of the month or so.
So now you've join the elite club of "Banned from HT", welcome to the crowd.:lol:(y)
I'm glad you got back to me from my initial PM there so you have a home.
 
Maraakate said:
That's nuts. Yes, it was that guy. He seemed reasonable, but I guess unfortunately he has to look out for his interest. I don't know if they get compensated or if he got a payout when VS bought it out and if he doesn't comply then he can lose that.
Click to expand...

He is a VS employee and was in no way connected to the birth of HT nor any of the content created there by the founders and many knowledgeable members that came along after HT opened in 2008. He got none of the profits when VS bought Forum Foundry in 2014 (and the holdings of FF thereof which included HT, bought from the original admin who helped the founders start it - right out from under the founders). He's a company guy who VS brought in to guide the ship after over a year without a true, regular admin presence daily, and all he does is the minimum. He answers few real questions because he isn't knowledgeable about the actual subject bikes the forum represents.

Maraakate said:
With that said, I appreciate all the support on here. Once things start picking up with production in the upcoming month or so I intend to place a donation to you guys to help with hosting costs and to let you know that I appreciate letting me post here about all of the work that I've been doing on it.
Click to expand...

As I mentioned previously, we're happy to have you here and we totally understand the value and benefits of what you're working on. We'll discuss the donation situation privately, no hurry at all.
 
Thanks, I was unaware of that group; I've since joined it. There's a couple of other ones on FB I was trying to be active in here and there over the years, but it seemed mostly groups for people to show off their builds.
 
Boomer343 said:
I would speculate that the VS adin saw you posting here and decided to cut you loose rather than share your expertise.

Dicks.
Click to expand...

Yeah, I kind of figured that was a possibility as well. I assume the "other" forum admins are monitoring conversations on here when they can.
 
STATUS UPDATE 06-15-2022:

* As mentioned previously, e-commerce page is now available. Includes pricing for a DIY solder kit and for a pre-soldered and tested kit.
* Put at least 50 miles so far on my design. Plan to ride it a good 40-50 miles tomorrow on my way back and forth to work. So far it's been working great.
* My friend started making progress on my measurements for the case last night. I'm going to meet with him tomorrow to loan him my original CDI in case he needs it for additional measurements.
* I also got a hold of another friend who has a 3D printer, so he's agreed to 3D print the case prototypes to test out the mounting before I send the CAD files off for sheet metal fab quotes.

CDI_Case_CAD.jpg
 
Boomer343 said:
I would speculate that the VS adin saw you posting here and decided to cut you loose rather than share your expertise.

Dicks.
Click to expand...

Maraakate said:
Yeah, I kind of figured that was a possibility as well. I assume the "other" forum admins are monitoring conversations on here when they can.
Click to expand...

Unless they have a spy here, we have limited the sections visible without being a logged-in member so much of our discussions can't be viewed, even by Keith who snuck in here like a member late last year. When we discovered he had gotten in I reduced his visibility to a handful of sections of little to no importance and I watch his profile daily to see if he returns. They're just being who they are, profit-first jerks who only care about the money for the corporation and their jobs. If the handful of us who are still answering posts there would stop doing it, the populace would get even less good information and would likely look around for other options sooner and find us more quickly. I really hate reading stuff like this from new members there ["Been reading up on threads here for upgrade ideas and glad to see this place still going strong"] because they are being totally deceived by Google searches that still find relevant old posts and they have no idea the place is only a shell of what it once was.
 
To be fair, most of the people who chime in with something like "Hey everyone, I just got this minty CB400T and want to turn it into a cafe racer. I'm planning on hanging a large 32mm Mikuni with pods, MAC 2-into-1, and <insert whoever makes aftermarket adjustable curve CDI here>. Glad to see this site is still going after all these years." end up not listening to experienced people and end up chopping the bike in bad/dangerous ways and never finish that build anyways (and eventually stop posting on that forum after a couple of months). There are real examples of experienced people on here who know what you should/shouldn't do if you must modify it all out like that. But, I see it's usually young people who think working on a vintage bike is easy because everything is smaller and "appears" simplified but that's really not true. It's not a modern car where you can just plug a USB cable in and start hacking away and hang some ridiculous air filter on it and the ECU will mostly compensate.

This is kind of off-topic, but those types of threads and builds always make me sad. I've worked on bikes for people before where I've been paid to undo their damage after they realized they can never get it to run right. And usually by that point they ignored the advice of forum members to keep all the older parts, so they get to rebuy it all over again at used ebay buy-it-now rip off prices. Then you think about, how many of those hacked, unfinished bikes ever reach a point where it reaches someone like me who undoes that damage? I'd say not many, because most people aren't willing to pay what that will cost. It's usually easier to scrap and get another bike and this just leaves less working examples out there.

But I digress, not all builds are bad. If you know what you're doing and take your time and care then some people can get creative and come up with some real thoughtful designs. This is not a personal slam against anyone here who is looking to mod, but rather a criticism of the fad of doing so and not listening to advice.
 
STATUS UPDATE 06-16-2022:

* Epoxy arrived today. Should be plenty to do at least 20 CDIs, possibly more.
* Friend has finished the AutoCAD model, then was passed over to my other friend to 3D Print the prototype case. He's going to throw it in his 3D Printer queue over the weekend.
* Made some progress with reverse engineering the change relay. For those interested, you can measure across the mystery transistor by attaching a volt meter to the green/red (starter) and green (ground, you can use any ground). On the original it should be about 0.7V in order to turn "on" the transistor which is needed for the starter to work. In the reverse engineered design I had about 1.3V. Has to go lower, I tried lower the resistance got it down as far as 0.8V. At that point, I was using a 47 ohm resistor, so I figured I'd just try removing the resistor entirely. Well, the transistor went up in smoke at that point. Will have to try again with 10 ohm or 22 ohm. If it still pops, then I would guess that means I need a beefier transistor. Shared this info with my EE friend and he said this was helpful and will look into it more for me to find out what we need to do to get it there. Other FYI notes on the change relay: If you measure across the same terminals I mentioned above, in gear it will read about 11 volts (maybe higher depending on the battery voltage, didn't bother to test that). This test is actually useful information as it could help someone else determine if the transistor is internally bad. Anyways, work continues on that as well.
 
Boomer343 said:
https://www.welshbordercarclub.com/product-page/genuine-lucas-wiring-harness-smoke

Maybe a Go Fund Page could be started to buy you a supply of this product! VBG
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Hah, well to be fair nobody knows what the transistor was in that change relay so some research will be needed to find something with the right specs and values. I did note that even though the starter was disabled you could start it with the kickstart and the lights worked. But it was very likely it was not running at the 7.5 degrees timing in Neutral. Didn't bother to check with a light. But this does mean it's possible to bypass the change relay for testing if you don't care so much about losing neutral.
 
For those interested in the change relay reverse engineering: the EE friend gave me a revised circuit to remove the BJT transistor and change it to a MOSFET with different resistance values in thr circuit that will perform the same function. Wont get around to doing this for a week or two.
 
Maraakate said:
For those interested in the change relay reverse engineering: the EE friend gave me a revised circuit to remove the BJT transistor and change it to a MOSFET with different resistance values in thr circuit that will perform the same function. Wont get around to doing this for a week or two.
Click to expand...

Good stuff, keep it coming. (y)
 
You can jump the wire from the the starter button to the magnetic switch and use the elec starter. With the change switch relay off the SCR 2 gate in the CDI is no longer grounded and the motor will only fire at 15 degrees timing.

The transistor was used as a switch. When turned on by the change switch the starter circuit was grounded thru the relay and the starter would work. The SCR 2 gate was grounded and the motor would fire at 7.5 degrees timing.
When shifting into 1st gear the transistor was turned off and the starter was no longer grounded and would no longer work. The SCR 2 gate was no longer grounded and the motor will fire at 15 degrees. timing. By removing the relay the only thing you lose is the safety feature of the elec starter not working when the motor is in gear and the lower ide when in neutral.

Bill H
 
Yes, but it would be good to have it reverse engineered so we can have some plug and play unit instead of having to jump things around and disconnect things. Also, just documenting for documentation sake is always good for these antiques in my opinion.

You are right though, and the theory lines up with the technical info in the FSM. So, I suppose if you bypassed it entirely with your method the timing marks would always line up to 'F' with a timing light and your idle at neutral would be a bit different.

I am curious though, if the 15 deg at neutral would cause the bike to overheat with excessive idling in neutral or is that more of an elementary thing where it would never actually happen unless you were idling for 10 minutes at a rally or started the bike in winter and walked away for 30 minutes and forgot it was running?
 
You can buy new shift change relays on the net so why make one unless you just want to ? The change relay also controls the side stand switch and the change switch so there is more than just the transistor.

Bill H
 
Where can you buy new change shift relays for the CM400A? Same dimensions, plug and play? I was unaware it was already reverse engineered.

I know it's part of the side stand switch and the change switch in order to provide power to the dash bulbs for the gear indicator and also to trigger that transistor for the timing to the CDI. The schematic of it is pretty simple. I'll have to post it here when I get back later, getting ready to head out. But basically the heart of it is the transistor, the rest is just the 12V, Starter, 1, 2, Light Blue to CDI, Sidestand that all work around this with some various diodes and resistors for triggering.
 
Watching you two discuss and collaborate is great, and it will benefit everyone who has an A model. (y)
 
STATUS UPDATE 06-20-2022:

* Took a 50 mile ride out to my friend who did the 3D prints of the case. Was a good "eat my own dog food" test for the new CDI. Passed with flying colours.
* The 3D printed case is 10mm higher than the original, this is on purpose to allow some additional clearance for the SCR transistors in Rev 4. Rev 5 it won't be an issue, but I'd rather have that extra security. Plus, it won't affect any clearance issues.
* The case appears to line up the same, will have to test it this evening.
* Grommets from McMaster Carr showed up and they wont work. So I'll have to go to Fastenal or Grainger, see what they have. If I can't find something I like we'll have to do another revision to the case to work with a grommet that I can easily source. Getting a custom one made up is probably more money than it's worth for such a small run. If anyone has an ideas on this, I'm all ears.

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