Xs850, key won’t kill power or engine

[NJRaised]

Started up my 1980 xs850 today and took it for a good ride. Ran great. Went to turn it off, turned the key to “off”, and nothing happened. Engine kept running and electrical power was still on. Even removed the key, bike kept running. I was able to kill the engine with the handlebar mounted kill switch, but I still have electrical power.

Where do I look first to diagnose this? I’m thinking a broken ground wire or bad ignition? Never had a problem before .

Thanks in advance

 

[Signal]

The first thing I would check is the switch itself. Is the wiring stock?
Do you have a stock ignition system? If so interrupting the power to the ignition stops the engine.

 

[nj1639]

I'd be inclined toward the key switch too.
Maybe spray some contact cleaner or wd40 in it and cycle the key a few times.
5Twins has breakdown of the xs650 key switches some where's around here.......might be the same for your 850.

 

[NJRaised]

Is the best way to check the key switch to add some wd40 and turn with key in? I’m mechanically inclined, electrical I really struggle with, hence my love of old bikes

 

[Jan_P]

Yes to check Ignition Switch
On 650 there is power feed from battery to switch if something is connected or it has shorted on that feeding wire upstream from Switch it bypasses the switch.
It can also happen for some circuits without battery should the charging kick in
Once started it runs on that.

Kill Switch or gear in and low rpm clutch out stalling it.

Has Something been changed on the machine or same as before ?
Maybe check wiring close to the switch up streams , Entering the headlight bucket ?

 

[nj1639]

Is the best way to check the key switch to add some wd40 and turn with key in? I’m mechanically inclined, electrical I really struggle with, hence my love of old bikes

I'll say my lawn tractor sprang a devastating hydraulic hose failure and made it almost to the barn. It sat outside through a rainstorm or two until I could get it back up to snuff. Dummy me left the key in the ignition.
When I went to fire her up the startup dash lights and the diesel plug prep were wonky at best. A squirt of wd40 into the key slot and then some cycling of the key on and off restored her to good order.

 

[Lou_TX]

Agreed. The ignition key switch is the main source of power to the motorcycle. If it does not shut off power, it is faulty.
(Unless there have been some undocumented modifications performed to the electrical system)

 

[Lou_TX]