Yamaha XS400 Cafe Build Wiring Question

[Njizzo12]

I've recently took my 1981 xs400 wiring harness apart and only wired up the things i need. Its going to be a kick only bike and the front and back brakes are the only things i need to work. I found this wiring diagram and wired it exactly how it is but it will not start. The starter motor is making a winding noise everytime i kick it over as well and there is know spark on both spark plugs. Let me know if you see any problems with this wiring diagram, Thanks.

problems with this wiring diagram, thanks.

 

[BBS360]

What's with all these wiring diagrams with only one fuse? Seems like trouble waiting to happen....

You're just hearing the starter motor clutch spinning when you kick. Might as well remove the starter chain, plus the starter clutch and motor if you want to save the weight. Would need to fabricate something to mount the starter motor cover over the hole, since the cover bolts to the starter motor.

Regulator/field coil wiring is wrong for your year of bike. Might be but isn't necessarily your problem but the battery won't charge at all.
It shows a green wire and ground going to the alternator. Those are for the field coil, but for your year of bike it should be have the green wire as shown but no ground. Where it shows a ground the field coil should connect to the same brown wire feeding the regulator.

Also, do you have a 2-position ignition switch as shown?
One position for running, one for lights only?
What's that N on there? Neutral switch/relay? Using it?
I'd changd the brown wire from feeding off the blue wire to feeding from the same source as the ignition unit/coils.
As drawn it'd be an unnecessary drain on the battery when you use the lights-only switch position.

Maybe someone else will spot something but the diagram doesn't look horrible otherwise.
I trust you've noticed it only shows one brake switch, when you've mentioned you want front and back?

 

[BBS360]

Meant to elaborate on the neutral switch and/or relay.
It doesn't show enough wires to make that work. Normally it goes through a relay which is activated by the neutral switch and enables the starter motor.
Obviously you're not using the starter motor but if you've tried to incorporate that function it might be disabling the ignition system.

Also double-check that your left cylinder pickup actually goes to the correct wire on the TCI, ditto for the ignition coils.
Wouldn't take much on a rewire to cross either of those and fire the wrong cylinder.

 

[Njizzo12]

Hi thanks for the response i have a two position key switch and it has three wires coming off of it. Does the engine shut off and run also have to be used? Or can i just use the igbition switch. And do you know of any wiring diagrams i can use for a kick only bike? Thanks.

 

[BBS360]

You could just use the ignition switch. Up to you.
It is good to have an obvious kill switch, not that the stock shutoff is super conspicuous.

That diagram is one of the better simplified kick-only ones I've seen.
Other than the issues listed above I think it looks sufficient to get the bike running.
Fix the regulator wiring, wire the front brake switch in parallel with the rear, and try it again.
My 360 didn't like starting without the field coil hooked up. Should do but just didn't. A bit of a mystery.
With any luck the regulator fix might get you going.

 

[Jeff0133]

I would keep the kill switch....it's a safety issue...