Help please bike shuts off while riding

[Riddellw1]

Hey guys, I'm new to this thread and I have a generally good idea on how to maintain XS400's. I have a 1982 motorcycle, it has no customizations OTHER THEN new handle bars.

So I'll be riding it, and randomly, literally randomly, any gear any speed or idle, it shuts off.
When I say shuts off I mean the engine just turns off, slows to a stop and throttle doesn't work. I know this isn't a fuel or air or combustion problem because of how sudden the shut off is.

When it does turn off, it WILL NOT turn back on for at least two or three minutes. After that, it starts right back up perfectly fine, and drives perfectly fine up until it shuts off again. As far as I know, the lights turn off but I just have to turn the key off and back on and then the lights are fine and the neutral light and oil light are back on.


Another annoying thing, is that it will go a couple of days where it DOES NOT STALL WHATSOEVER. I'll drive it for hours, no problem, wake up the next day, drive all day, no problem, wake up the next day, and it shuts off while riding.


What I have tried to do to fix this, I've checked the voltages of the battery and ignitor, they're both good, I've tightened the terminals, they do seem to be a little rusty but I'm not sure if that's vital to the battery running. I've taken apart the right handle bar and looked at the killswitch on the inside and saw the two little silver contacts and they seemed to be clean. I've taken the ignition coils out and looked at them, not much else I could do with those but since my spark is perfectly fine on both plugs I doubt it's them

I have taken the safety relay out for the kickstand switch, and the bike still stalls. So I do know that it is NOT the kickstand safety thing.



If anybody can help me that would be awesome, I just want to be able to ride my bike again without worrying about it stranding me out in the road. Thanks!

 

[drewpy]

I would check the fuses. they may look ok but take them out and check for security.

 

[Joel]

I had a similar issue. It ended up being the clip for my ignition fuse was broken, but managed to stay in place. Most of the time it would make a connection, all of a sudden it would move a little and stall.
If that isn't it, I'd be looking at the wires coming off the ignition for any damage.

 

[eric123]

Check your coil too. Sometimes they work until they get hot...Quit working and then start working again when they cool down...

 

[HoughMade]

My bike did this- it was loose connections in the fuse box. With the bike off, turn the ignition switch to on without starting it and then moves the wires near the fuse box around to see if the indicator lights flash off. That will tell the tale.

 

[Riddellw1]

I'm going to go outside now and check the fuses but as far as I could see last time they did seem to be intact

Eric, The idea with the coils heating up too much and then the bike turning off has me a little worried because I guess it could be a possibility, however, wouldn't the ignition coils heat up FASTER if I was idling the bike rather then driving it because it's air cooled? My bike stalls way more often while I'm driving, it's more rare while I idle, although it does happen. Just a thought

Is there any way to check if there is something wrong with my ignition coils?

And joel, I will check the wires coming off of the ignition, but if they were damaged wouldn't they only effect start up and not the actual running of the bike when it's finally started?

 

[leedutcher]

check your kill switch too somtimes over the years corrtsion can get to the wire causeing bad connection. just an idea

 

[Riddellw1]

Hey guys,
I checked the killswitch again and all seemed to be perfectly fine, there wasn't much I could do to tell if it was bad, but it all seemed connected.
I checked the fuses and one of the silver connectors was flipped upside down, I took it off, turned it over and reconnected it, and it made no difference.
Any other ideas?

 

[drewpy]

check the wires that go into the fuse box

 

[Riddellw1]

The bike is no longer starting, the problem is actually getting worse now, anyone else have any ideas? I've checked the fuses, they are fine. I've checked the connectors, they appear to be fine as well.

 

[chartrain]

Hey guys, I'm new to this thread and I have a generally good idea on how to maintain XS400's. I have a 1982 motorcycle, it has no customizations OTHER THEN new handle bars.

So I'll be riding it, and randomly, literally randomly, any gear any speed or idle, it shuts off.
When I say shuts off I mean the engine just turns off, slows to a stop and throttle doesn't work. I know this isn't a fuel or air or combustion problem because of how sudden the shut off is.

When it does turn off, it WILL NOT turn back on for at least two or three minutes. After that, it starts right back up perfectly fine, and drives perfectly fine up until it shuts off again. As far as I know, the lights turn off but I just have to turn the key off and back on and then the lights are fine and the neutral light and oil light are back on.


Another annoying thing, is that it will go a couple of days where it DOES NOT STALL WHATSOEVER. I'll drive it for hours, no problem, wake up the next day, drive all day, no problem, wake up the next day, and it shuts off while riding.


What I have tried to do to fix this, I've checked the voltages of the battery and ignitor, they're both good, I've tightened the terminals, they do seem to be a little rusty but I'm not sure if that's vital to the battery running. I've taken apart the right handle bar and looked at the killswitch on the inside and saw the two little silver contacts and they seemed to be clean. I've taken the ignition coils out and looked at them, not much else I could do with those but since my spark is perfectly fine on both plugs I doubt it's them

I have taken the safety relay out for the kickstand switch, and the bike still stalls. So I do know that it is NOT the kickstand safety thing.



If anybody can help me that would be awesome, I just want to be able to ride my bike again without worrying about it stranding me out in the road. Thanks!

The old glass fuses & spring clips can cause you grief
I had the same problem, sometimes it would cut out then restart with a huge backfire from gas still pumping in. I first found the main power supply fuse was bad despite looking good. It was unsoldered at one end but you couldn’t see it. Then the spring clips holding the fuses lost tension causing intermittent cut outs. I replaced all the fuses with inline modern blade type fuses & so far (2years) so good

 

[avemachina]

Silly question, but--you're sure your battery is topped up? Also, I'm unfamiliar with the '82s (is that the year the DOHCs started?) but does this model have a kickstand switch? That might be malfunctioning.

The other thing I'm thinking is maybe the clutch safety switch (the one that's connected to the clutch lever). I know on mine if my lever isn't tightened in all the way, it's a little wiggly and I don't hear the "click" of the relay even if the lever is pulled in, and the bike doesn't start. When you've set your killswitch to RUN and you've got your key on "ON", but your engine is off, if you pull your clutch lever in do you hear a click? There's a safety relay that could be the culprit as well. I swapped my levers for adjustable ones, and you mentioned different handlebars, so potentially there might be something to this.

My thinking is that if the fuses are OK and the connections are OK, it might be one of the various little safety shutoff sensors being loose or rattled in such a way to make them activate and go "NOPE" whenever you're riding.