Honda CX 500 Forum banner
1 - 11 of 11 Posts

· Registered
Joined
·
37 Posts
Discussion Starter · #1 ·
I posted this in the tech help forum before i even realized there was a forum for custom/mod topics, i think it probably belongs here instead...(pasting the text)



okay, first off, since i still haven't changed my signature, i have an '81 cx500C...now, down to business. i'm turning this bike into a custom something or other (most likely café racer) and i want to dramatically reduce the stuff on this bike, including the wiring. what i want to do is dump the ignition switch and key, and use a switch with push start set-up, that is, have a switch that turns on all systems and doubles as a kill switch, with a push button start to activate the ignition process. i'd like to keep brake lights and turn signals, and i can go either way on the high beam, though it'd be nice to have, just in case i want to take my handy to spotlight for deer in the field. i just finished browsing all 14 pages of the tech forum and have seen some useful info in the form of wiring diagrams (which i've downloaded and will definitely use), but what i'm looking for now is any advice from anyone who has done this in the past. i mean, i am fully prepared to spend a few days and brain cells tracing wires and trial-and-error testing, but if there's anyone who knows what's up already i'd appreciate the info. is it even possible to do this with the cdi/stator system? i'm not an expert on bike wiring, so anything i do at this point is pretty much shooting in the dark. any ideas? i guess my main area of concern is condensing everything the ignition switch does into a single on/off switch...but given my limited knowledge in this area, i may well be vastly understating the challenge ahead.



thanks!!



~J
 

· Registered
Joined
·
41 Posts
Your key switch, is just an overkill on off switch. all the major electrical loads are handled by relays and solenoids. I have yet to tear into my cx harness, but bike wiring is pretty simple in general. the best advice I can give for putting your harness on a diet is to study each electrical system individually and get a full understanding on why it is there and how it works with the rest of the bike's electrical system.
 

· Premium Member
Joined
·
2,333 Posts
Welcome to the forum, SVR. Please take a few minutes to edit your profile to show your location and to edit your signature to show your bike's year and model.



Your advice regarding studying the wiring is spot on, IMO. There is no real substitute for understanding how something works before trying to modify it. Otherwise it comes down to groping along and hoping to get lucky, with frustration almost guaranteed.




The wiring is pretty simple on these bikes and schematics can be found in several locations. My personal preference is the wiring diagram in the Honda factory service manual for the bike under consideration.



In its stock configuration there are only two relays on the bike - the starter relay and the turn signal flasher relay.
 

· Registered
Joined
·
18 Posts
This can be done pretty easily.



The ignition switch does three things- It connects the red and black wires when the bike is on, shorts the CDI to ground when the bike is off, and lights the rear tail lamp when the switch is in Park.



You only need to provide for the first two.



Get a bigass DPDT switch from an offroad truck supply. It should be waterproof and rated for 10A. It will have two common terminals in the middle, two UP terminals, and two DOWN terminals. When the switch is UP, each common terminal is connected to each of the UP terminals, and to the DOWN terminals when it's down.



The switch can be used in a different way than usual for the CX. Connect the two common terminals in the middle with a piece of 16G wire (solder or 1/4" crimp spade fasteners). Connect the red and black wires to the UP terminals. Connect the green and black/white striped wires to the DOWN terminals.



Ignore and wrap the brown and brown/white wires by themselves in electrical tape. Nobody uses that dumb parking light anyway.



When the switch is up, the 12V is connected from the battery to the starter and light circuits. When it's down, the lights are off and the CDI control wire is shorted to ground, stopping the motor.
 

· Registered
Joined
·
41 Posts
Welcome to the forum, SVR. Please take a few minutes to edit your profile to show your location and to edit your signature to show your bike's year and model.



Your advice regarding studying the wiring is spot on, IMO. There is no real substitute for understanding how something works before trying to modify it. Otherwise it comes down to groping along and hoping to get lucky, with frustration almost guaranteed.




The wiring is pretty simple on these bikes and schematics can be found in several locations. My personal preference is the wiring diagram in the Honda factory service manual for the bike under consideration.



In its stock configuration there are only two relays on the bike - the starter relay and the turn signal flasher relay.
I have been a member here and on the old forum since March when I picked up my 78' CX500 in march of this year... check out Father Daughter Build for more info on my bike.
 

· Registered
Joined
·
180 Posts
I have changed the old switches with new (F4) switches so I am familliar with the electrical system. There is really not much to be saved by taking wires off the stock harness. Most of the harness is under the tank therefore out of sight. Also all of the wires are needed. Your best bet is to relocate the battery under the engine and free up the space where the batery and airbox resides. This will give a clean cafe racer look. You will need to make a batery box and use a smaller battery. I use the one for a Yamaha R1. The regulator can be relocated to the batery box so that will clean up the right side of the bike. Just my own opinion.
 

· Registered
Joined
·
37 Posts
Discussion Starter · #9 ·
I have changed the old switches with new (F4) switches so I am familliar with the electrical system. There is really not much to be saved by taking wires off the stock harness. Most of the harness is under the tank therefore out of sight. Also all of the wires are needed. Your best bet is to relocate the battery under the engine and free up the space where the batery and airbox resides. This will give a clean cafe racer look. You will need to make a batery box and use a smaller battery. I use the one for a Yamaha R1. The regulator can be relocated to the batery box so that will clean up the right side of the bike. Just my own opinion.




I was thinking about the battery relocation...i was originally planning a monoshock conversion, hence the battery problem, but figured i'd have to switch to a sealed battery, turned sideways, mounted under the engine to pull it off. i've since moved away from the monoshock idea (for now) but i'm still deliberating the battery move. the cx definitely looks better either completely open in that area or with the side covers on, and with pod filters i wouldn't want the side covers there anyway. i'm still planning, i'd like to do something other than standard cafe racer as well, but right now i'm still taking apart and scrubbing down all the pieces, so i've got some time still to think about it. and regarding the wiring harness, what i really wanted to do was just get rid of the ignition switch and condense everything into one switch and push-button set-up. to make it easier for the bike thieves out there.
 

· Registered
Joined
·
1,161 Posts
I was thinking about the battery relocation...i was originally planning a monoshock conversion, hence the battery problem, but figured i'd have to switch to a sealed battery, turned sideways, mounted under the engine to pull it off. i've since moved away from the monoshock idea (for now) but i'm still deliberating the battery move. the cx definitely looks better either completely open in that area or with the side covers on, and with pod filters i wouldn't want the side covers there anyway. i'm still planning, i'd like to do something other than standard cafe racer as well, but right now i'm still taking apart and scrubbing down all the pieces, so i've got some time still to think about it. and regarding the wiring harness, what i really wanted to do was just get rid of the ignition switch and condense everything into one switch and push-button set-up. to make it easier for the bike thieves out there.


Installed pod air filters and a battery/regulator tray in the following photos. Used 6061T6 .040" sheetmetal and angle for most of the installation except for 1/8"X1" steel straps for original battery bracket installation and .040" side covers.





Working on the wiring at this time with the ignitech ignition:















 
1 - 11 of 11 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top