Maraakate
Veteran Member
Thanks to a kind donation from Jim I received 5 broken CDI units as was able to use these to successfully reverse engineer the CB400/CM400 manual series CDI.
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!
You can order the complete plug and play unit here. Other ordering options include my ebay store https://www.ebay.com/usr/eggmatorch, David Silver Spares, direct PM on VHT, or via E-Mail.
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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Original thread:
I've started to work on one that had the wires already cut close to the grommet. This time I tried a different strategy of using a 1000w heat gun and slowly breaking apart the potting compound. Once the top was exposed, went around the corners with a brass chisel to expose the PCB ends. Then heated the back of the unit for about 2 minutes and was able to lift it out. From here I have been able to clean up the back of the PCB for the traces.
Some interesting notes compared to the CM400A CDI (at least in this revision): The wires are all arranged in a "bus" like format so they're all right in one spot. On the 400A CDI they go wherever so wire lengths vary. There are 3 through holes that are not connected to anything. Unsure of the schematic, but may have been leftovers from the 400A safety lockouts or this board is also used in other models from the same era with additional safety features. The board is larger than the 400A CDI PCB but is much more simplified. There are 4 film capacitors on this board, compared to 2 on the 400A CDI. This PCB also had a plastic piece for protecting shorting out the PCB on the metal case. The 400A CDIs I've taken apart it appears they poured a few mm's of potting compound, waited for it to flash off, then laid the PCB down and finished pouring the rest.
Ignore the bubble on the large main cap, that's from the heat gun.
Going out to get virgin paint thinner from autobody supplier to help remove the rest. Though, with this board I'm going to try this different approach and it may not be necessary. I see there is silkscreening with japanese characters on the board. I have friends who can read Japanese and can probably translate it. I'd like to see what it says.
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.
- DSS now has it available. You can get it here with your weekly DSS fix via this direct link or searching manually for the part number: https://www.davidsilverspares.com/CB450SC-NIGHTHAWK-1985-USA/part_392654/. I've informed DSS that it fits other models, so it should show up for CM400T/E/C, CM450E, and CB450SC. If it doesn't please let me know so they can fix it.
It should be showing up for other model years, if it's not let me know so they can fix it. - 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, David Silver Spares, direct PM on VHT, or via E-Mail.
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.
-----------------------------
Original thread:
I've started to work on one that had the wires already cut close to the grommet. This time I tried a different strategy of using a 1000w heat gun and slowly breaking apart the potting compound. Once the top was exposed, went around the corners with a brass chisel to expose the PCB ends. Then heated the back of the unit for about 2 minutes and was able to lift it out. From here I have been able to clean up the back of the PCB for the traces.
Some interesting notes compared to the CM400A CDI (at least in this revision): The wires are all arranged in a "bus" like format so they're all right in one spot. On the 400A CDI they go wherever so wire lengths vary. There are 3 through holes that are not connected to anything. Unsure of the schematic, but may have been leftovers from the 400A safety lockouts or this board is also used in other models from the same era with additional safety features. The board is larger than the 400A CDI PCB but is much more simplified. There are 4 film capacitors on this board, compared to 2 on the 400A CDI. This PCB also had a plastic piece for protecting shorting out the PCB on the metal case. The 400A CDIs I've taken apart it appears they poured a few mm's of potting compound, waited for it to flash off, then laid the PCB down and finished pouring the rest.
Ignore the bubble on the large main cap, that's from the heat gun.
Going out to get virgin paint thinner from autobody supplier to help remove the rest. Though, with this board I'm going to try this different approach and it may not be necessary. I see there is silkscreening with japanese characters on the board. I have friends who can read Japanese and can probably translate it. I'd like to see what it says.
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