Topic: Hot wire '78 Honda Hawk 400t

[Schnell]

So I've got this project bike without a key. I removed the ignition switch with harness and can't see a key code number. Before spending money on it, I'd like to see if it runs by imitating the function of the ignition switch with wire jumpers in the ignition plug in the headlight bucket. There are 6 wires: red, black, green, brown, black with stripe, brown with stripe.

Im not so good at reading wiring diagrams, so before I short circuit something, can anyone tell me what to connect with the jumpers so that I can use the starter button to try to start the motor? I think brown wiring is for lights, which I don't need for this test.

(A PM works if you don't want this to become knowledge for thieves.)

Thanks!

[calj737]

Typically,

Red to battery +
Black switched 12v
Green ground
Brown/BRWN stripe supplemental lighting
Black stripe ignition circuit

From what you describe, jumper battery + to handlebar BLACK. This should deliver 12v to handlebar and START thru KILL switch. You can check this by measuring output of solenoid wire for 12v when jumpered.

Be careful and don't leave any fingerprints. If you get knicked by 5-0, you never heard of me 

[Schnell]

Thanks,

So red to black, and also red to black with stripe?

[calj737]

Shouldn't need red to BLK/stripe. That should occur internally at handlebar control. Just red to battery + then to handlebar BLACK.

[Schnell]

Okay, thank you.

[HondanutRider]

Hey Frank, I've got a set of jumper wires with pins on the end to jump into the plug where you disconnected the switch from.  If you want to borrow, let me know.

All you need to do is manually connect the wires that the switch make connection with.  Usually only the red to black is all that is needed.  On my 350 Four, there are only 4 connections.  The black/white wire runs off the engine stop switch to provide power to the coils, which gets fed live from the switched black line.

If you have a wiring diagram for your model, I could probably help read it for you.

[Schnell]

Thanks Bob. We should get together sometime next week.
I found the wiring diagram on the interwebs.

[HondanutRider]

Looking online at what I think is your wiring diagram, it looks like the in the ON position the switch connects the DarkGreen wire to the Black and the Red wire to the Brown.  That is if your bike was the CB400(Hawk II) for which I looked at the wiring diagram.  At least the wiring colours for the switch match what you described.

[Schnell]

So I connected red to black, hooked up a battery, and the starter button activated the starter motor which turned the engine over. I sprayed some quick start into the carbs but heard no ignition. It's a good start, I mean beginning, anyway. Should see if there is a spark at the plug.

Next step is to set the valve clearances.

[HondanutRider]

If I'm looking at the correct wiring diagram, its a bit convoluted but I believe you will have only activated the starter button circuit by just your connecting Red and Black.  To correctly mimic the key switch, you need to connect the two sets of wires I indicated earlier.  This should also activate the ignition.

This is the diagram I looked at: http://www.cmsnl.com/classic-honda-fansite/honda_wiring_diagrams/CB400%28HawkII%29.jpg

[Schnell]

So,

DarkGreen wire to the Black

and the Red wire to the Brown?

No red to black?

Thanks Bob!

[HondanutRider]

So,

DarkGreen wire to the Black

and the Red wire to the Brown?

No red to black?

Thanks Bob!

Yes, according to that wiring diagram.

[Schnell]

Okay thanks. I'll give that a try when I get the chance.