Need some Help from electric Guru's...1981 CB750K......FIXED & WORKING.....

[cklamer]

Okay been going back and forth with the electrics. I have taken it on and off of the bike 3 times and I am tired of it.

Pretty much using the stock wire harness and all that has been done is delete the plugs and wires for the pulse generator and the CDI units and the coils since we are replacing everything new with a complete Dyna Ignition.

I am also replacing the speedo unit with an all digital unit from Acewell. Now with that I followed the wiring diagram and tapped in to the stock speedo units wires in to the plugs that were with the unit. So the Nuetral wire to their nuetral wire oil sending unit to theirs and so on. Now there is a VDD wire ad read online it goes to the plus side of the ignition. I connected everything to the stock units switched wire.

Now the other item I did was run the wiring for the fuse block to the back of the back under the seat and hooked everything up to the Fuze Block brand fuse block. It has the constant 12V in the Switched 12V in and th Ground in and has 6 spots out. You can pick if you want to use constant or switched just by placement of the fuses.

So ran everything hooked my Shorai battery up turned the key nothing. No headlight no speedo unit nothing.
Don't have a very good multi meter but was showing voltage going to the fuse block and going from the fuse block.
But with the plug from the stater solenoid to the Rectifier plugged in suddenly I am getting a constant feed to the fuse block and if I unplug it then the key turns the Fuze Block on and off you can hear it click and voltage goes on and off.
The only thing I can come up with is maybe the Starter Solenoid is bad and is keeping a line current open.
No I do not have turn signals hooked up yet or the oil switch and nuetral switch since I don't have the engine.

I wanted to get the electrics run, tested and working before the bike goes to the engine builder to be installed.

The wiring diagrams are confusing on these bikes since it doesn't really give you a flow diagram from the battery and the rectifier to the ignition switch.

Thanks and I appreciate any help.

By the way I did go ahead and order a new OEM Starter Solenoid I should have it by Friday.

 

[kraptastic k]

Re: Need some Help from electric Guru's...1981 CB750K

I'm going through the same woes on my bike. We are using:
OE harness
new headlight
new starter relay
new high-output ignition coils
used spark units
new universal headlight switch
new AGM battery

and with all of this installed correctly, we are still having starting issues. We can hotwire the bike by crossing two of the wires on the right side bar control, but we can't keep it running that way. And we aren't even trying to run turn signals!

I wish I could tell you what to do, but my electrical knowledge is less than basic. My current plan is to buy an OE kill/starter button and plug the bastard in, then ride it to a real bike builder and get a better plan. Hopefully that builder will see this post!

Good luck,

krap

 

[notlob]

Re: Need some Help from electric Guru's...1981 CB750K

If memory serves me well, you need a constant 12v and a switched 12v for the acewell. Is that what you have?

You need the reg/rec plugged in as well to complete the circuit, otherwise its just like removing the fuse from the solenoid.

You can test the neutral and oil light are working on the acewell by grounding the green for the neutral and black for the oil light at the connector plug for the pulse generator.

 

[cklamer]

Re: Need some Help from electric Guru's...1981 CB750K

The only thing I see on the Acewell schematic that might be a constant is the clock everything else is switched 12V.

I am going to pull the wire harness one more time and run the VDD to the Black & White wire coming directly off of the ignition switch and that should be the positive out from the ignition correct.

Then I am going to completely redo the fuse block. I am getting rid of the fuse block and running all inline fuses as recommended by DCC. The fuse block I have may be causing some of my issues.

Plus I can't make all of the connections because I have no engine but it should still turn on. I know it will it's just that it's not turning on the correct way.

If this doesn't work then I have gasoline and a match. ;D

 

[cklamer]

Re: Need some Help from electric Guru's...1981 CB750K....FIXED

YAY....IT'S ALIVE.......
After pulling the Wiring Harness AGAIN! I moved the VDD wire from where it was run to the positive out of the igition switch and made sure I had a constant and a switched 12V for the clock.
Then pulled and got rid of the Fuze Block which may have been most of my problem in the first place I then added all new inline fuses for each of the fused lines and I went on to add another frame ground for the stock ground buss connection in the wiring harness.

So once I did all of that verified all of the solders and re-wrapped the harness AGAIN I took it outside plugged everything in checked the temporary frameground I am using hooked the Shorai battery up and first thing I noticed was the clock was working so I reached up turned the switch and everything came on as seen in the pictures below. I think I wet myself I was so happy that it was working now the tank, seat and fairing are all on and it's off to see the wizard the wonderful wizard of engine building. ;-)