Honda CX500 Motorcycle CDI ignition unit

[stj]

Re: Honda CX500 Motorcycle CDI ignition unit

is something wrong with the original box?
why not just sray conformal coating on the board or paint it with rubber and then use the original box?

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

Will this enclosure fit? Bud PN-1323-DG
It's the same size as Finnbox but thicker and people were using Velcro to mount it. I'm not happy with all that but it needs to be waterproof because of the high voltage. If you know of something better, I'm all ears. I have all the part values and circuit.

Just took a look on my bike and the CDI box sits in a recessed space in the frame, below the seat. Your box would not fit as the space available is not much bigger than the original CDI box which was 134 x 65 x 35.
The maximum size of the recess in the frame you can see in the picture is: 130 x 65 x 35mm.

The maximum size in the tail space behind seat is 180 x 90 x 45mm

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

Will this enclosure fit? Bud PN-1323-DG
It's the same size as Finnbox but thicker and people were using Velcro to mount it. I'm not happy with all that but it needs to be waterproof because of the high voltage. If you know of something better, I'm all ears. I have all the part values and circuit.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

Have you managed to get all you need Redwire? I've almost finished putting the old unit back together and just have a few broken resistors to replace. I am only reassembling it for reference purposes if needed.
Is there any more info you need from me Redwire.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

The module is located underneath the seat, away from the engine.

ABS rated -40°C to +80°C, no sunlight, I was using this it's low cost.
Polycarbonate rated -40°C to +120°C, UV is okay
Aliexpress rated nothing, melts if you look at it.

pic is of what the low profile finnbox looked like.

Yes you are right Redwire, the CDI box is located under the seat and is not in a exposed area to the wet. its more likely to just get damp under there.
The height of the box is more important than any other dimension as if its too high it might be subject to the seat pressing down on it or even the seat may not fit anymore. Otherwise there is plenty of room around it. If it was larger than the original it would be fine as long as its not higher.
I've spent hours going through that awful schematic and and following the circuit through against the real PCB. and I can only find one resistor R21 which is directly connected to R25 and R20. There is only physically one single R21 on this PCB which sits mounted vertically just to the right of R25 and below R20 (in tube). The value of R21 on my PCB is 910 ohms. see photo.

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

The module is located underneath the seat, away from the engine.

ABS rated -40°C to +80°C, no sunlight, I was using this it's low cost.
Polycarbonate rated -40°C to +120°C, UV is okay
Aliexpress rated nothing, melts if you look at it.

pic is of what the low profile finnbox looked like.

[stj]

Re: Honda CX500 Motorcycle CDI ignition unit

noooooooo......
you cant use thermoplastic on a bike - it will soften or melt!

[Per Hansson]

Re: Honda CX500 Motorcycle CDI ignition unit

Condolences for your loss!


A small idea about the box if you haven't already considered it is a custom 3D printed one.
Many places you can order 3D prints from models you provide...

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

My condolences on your great loss. I lost my mom suddenly years ago and I feel it was better than seeing her suffer slowly from some crappy illness.

Working on the project, best I could do is a PC board for a common 115x90x55mm box. Just too thick for my liking. Please advise if it will fit.

Best box (pic) is one Aliexpress box low profile but I don't know how long the boat ride would be.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

Thanks very much for all your doing for me. Just had a bad time last few days as I lost my mother due to a blood clot in her heart. I Will be back on in few days.

[stj]

Re: Honda CX500 Motorcycle CDI ignition unit

why not a cast or extruded aluminium box?

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

Stop making me laugh
Sort by size - haha 5,610 results fu
"waterproof" - no gasket lol avoid puddles
Comes with screws? - no
Dimensions drawing - not available
recycled plastic - maybe

It's chinese torture. These boxes come in standard sizes, all are way too thick over 2-1/4" 55mm.
For some reason the prices are actually the same through distributors, I wonder why the price is up there.
I did find the usual 115x90x55 though and only one box is slimmer but it looks a bit um uh low quality and reviews complain the plastic is hard and full of voids.

[stj]

Re: Honda CX500 Motorcycle CDI ignition unit

https://www.aliexpress.com/wholesale...of+project+box

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

I got stuck finding a waterproof box, finnbox appears to be 120x80x30mm and all I could find in North America is way thicker like 55mm. The next size down, smaller enclosures I couldn't fit all the parts on a pcb.
Looking at Bud PN-1323 or Hammond 1554F the 1554C is too small. Let me know what you think.
I can make a board made once I figure out the box size and thankfully the heat wave ended. I don't care about a few bucks for parts.

The other R21 that connects to R20 (220R) is 910R?

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

OMG Sorry Redwire that must have been a typo as your right R20 is red, red, brown, gold=220R.
Your right about the schematic being awkward to read. R21 is shown twice on PCB near R24 and its also next to C2. Oh and R19 is definitely 180R

Hey Redwire, thanks for all this help. i appreciate what your doing but please not at your expense. I am quite happy to cover any costs you incur. My CX500 could pack up at any time with a 1980 CDI unit and as I said it maybe whats causing the popping at exhaust when slowing off the throttle. Its definitely not the carburettors doing it and not the exhausts either. Can you make your own PCB's?
I have put the original PCB back together now so if making a new CDI is going to be a problem and the components like the SCR's I have on the original board are still available somewhere, I should be able to get this old one working again now.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

The heatshrink tubing is just insulation to prevent the part from shorting to parts next to it.
The CAL resistors are the ones sticking way out on pins past the edges of the board.

From your pics R20=220R (in the heatshrink) which matches other people's pics. Not 610R which does not exist as a EIA E-24 value. Where is that from? Who is 610.

The rajamolor schematic is so hard to read, R21 is referenced twice (one by CAL R24 and then one by R20 as well) looks like it is 110R or 910R. Can you check if there are two resistors getting mixed up.

OMG Sorry Redwire that must have been a typo as your right R20 is red, red, brown, gold=220R.
Your right about the schematic being awkward to read. R21 is shown twice on PCB near R24 and its also next to C2. Oh and R19 is definitely 180R

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

The heatshrink tubing is just insulation to prevent the part from shorting to parts next to it.
The CAL resistors are the ones sticking way out on pins past the edges of the board.

From your pics R20=220R (in the heatshrink) which matches other people's pics. Not 610R which does not exist as a EIA E-24 value. Where is that from? Who is 610.

The rajamolor schematic is so hard to read, R21 is referenced twice (one by CAL R24 and then one by R20 as well) looks like it is 110R or 910R. Can you check if there are two resistors getting mixed up.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

in this schematic of my CDI box I got here:
http://rajamolor.blogspot.com/2008/0...schematic.html
its shows that those tubes with a resistor sealed inside like R20 for example, are marked as "CAL"
would these be for calibration done in production.

[roadrash]

Re: Honda CX500 Motorcycle CDI ignition unit

What size is the original can? I couldn't find a waterproof box a decent size, popular is 4.53" x 2.56" x 1.58" (115x65x40mm) (i.e Bud PN-1321 too small) but then it jumps to 4.53" x 3.54" x 2.17" (115x90x55mm) which seems thick. Finnbox guy I guess people used Velcro to tie it down.

Did you get values for resistors R19, R21?

Original can is 92x65 by 45mm deep.

I am having trouble locating R19 but if the one I think is it then its as follows.
R19 =180 ohms???
R20=610 ohms.
R21=910 ohms.

[redwire]

Re: Honda CX500 Motorcycle CDI ignition unit

What size is the original can? I couldn't find a waterproof box a decent size, popular is 4.53" x 2.56" x 1.58" (115x65x40mm) (i.e Bud PN-1321 too small) but then it jumps to 4.53" x 3.54" x 2.17" (115x90x55mm) which seems thick. Finnbox guy I guess people used Velcro to tie it down.

Did you get values for resistors R19, R21?