Honda-SOHC
SOHC.co.uk Forums => CB750 => Topic started by: Dave B on January 30, 2021, 11:27:50 AM
-
Can anybody help?
I am in the process off rewiring front end of 1975 CB750FO to existing wiring harness.
I have the wiring diagram for this bike.
I have fitted a new righthand switch (supplied by David Silver) but some of the colours on the new switch don't correspond
to the wiring diagram or colour match the existing harness.
The starter button works(black and yellow/red).
I have connected the Black and red to the matching black and red on the existing harness.
I am left with Black and blue wire?
And two black wires with white stripe.One has a male bullet connection and the other has a female bullet connection.
Be very grateful for any help.
cheers Dave.
-
From memory and not that familiar with 750F The black/ white is the positive feed to both ignition coils (via the kill switch) and Black/red is the headlamp feed wire to the fusebox.
-
Thank you
Do you think the 2nd black/white wire is the live feed to the kill switch
-
as I say not an expert on the 750F but there should be a black/white wire that goes to the kill switch and then at the multi-bullet connector a black/white wire which runs to each coil. Basically the kill switch isolates the 12v feed to the coils when it is not in the central position. AFAIK the black/white wire doesn't connect anywhere else on the bike ... but a 750F expert on here may chip in and tell me otherwise ;)
-
If its a pattern switch(probably) the colours are frequently wrong. Try testing the continuity between the two black/ white wires with the kill switch in both positions, if they connect when switch is in run and disconnect when in stop connect one to the black/white in loom and the other to a black in loom if not come back to me for further tests.
You will need to find out where the black/blue goes in the switch.
Long distance electrical fault finding is a bugger
-
Not sure on USA wiring but, on the UK there is a live feed from the right hand switch that has to go to the left hand switch ;)
-
Thank you all very much
will let you know the results
cheers,
Dave
-
Just in case the wiring diagram you have is not clear here is the one I got with my bike.
(https://imagizer.imageshack.com/img924/3627/G3tulY.jpg)
Cheers
Dennis
-
cheers Dennis
-
SO,
Black and blue wire from run switch is the live feed
Black with white wire goes to coils.
All now working.
Tomorrow i start on the new lefthand switch!
Thanks for your help
Cheers,
Dave
-
SO,
Black and blue wire from run switch is the live feed
Black with white wire goes to coils.
All now working.
Tomorrow i start on the new lefthand switch!
Thanks for your help
Cheers,
Dave
I think plain black is +12v feed to kill-switch and the other side of that switch is black/white going to both coils .. not sure where black and blue comes into it. This link is a useful guide to Honda bike colour codes. http://www.satanicmechanic.org/wiringcodes.shtml
-
Do you know that is the wrong switch for a USA f there are no light controls on a USA Rhs switch. Just the kill and start button. The USA harness is different to the UK one.
-
USA switch from SIlvers.
TypeGenuine PartPart No_
35130377P00
35130-377-P00
Price£75.00
(£90.00 inc vat
-
Brilliant
Thank you
-
Might be genuine part number but the P00 means its pattern part, i thought looms were the same and just switched varied.
I dont remember black/blue being in ant Honda switch and i know some months ago it took several weeks and lots of e-mails to sort out a US site member who had pattern switches with ompletely wrong colours.
As long as you have verified that the black/blue goes ONLY to one side of the kill switch treat it as a straight black
-
Thats confirmed
Thank you
cheers dave