XJ1100 Intermittent Ignition Cutouts??? Help!

[dpo]

I have a 1982 XJ 100 Maxim that I bought two years ago and has been a great, reliable runner that I use use on a nearly daily basis and has run nearly flawless on two 800 mile round trips this summer to both San Diego and Los Angeles. (I live in Las Vegas)

My question is, two days ago, the ignition cutout and stopped the engine.

It happened once in Long Beach, and again a few months' ago, both for just a second and went away.

Then while on a ride around town, I stopped at a red light and while waiting, it did it again. The last time it happened, I thought the kill switch was slightly "OFF" and so I checked it first. All normal key ON lights were lit, but the starter would not work. after a few tries, everything was fine and I had it running before the light turned green.

Down the road, after a stop for an errand, it started up, ran for four seconds and cut off again. Repeated switching of the kill switch and key on and off did nothing. I started to check fuses and wiring under the seat and after wiggling here and there tried the starter and it fired up.

I made it another 2 miles down the road and it all started over again.

I don't think I actually 'fixed' anything, but I naturally want to know what could cause the dash lights to be ON, ready to start, but no response from the starter button, the, as if its like a circuit breaker 'resets' itself and everything is good.

I checked the main fuse, and tried the key with it both in and out, and or course with it out I had NO lights/power at all.

The fuses were all OK and the only other things I saw were the two flasher units for the signals and hazard lights.

Does the main ignition module have an electronic circuit breaker? For how intermittent it is, I don't think the problem is the wiring/ignition unit on the left side of the engine case.

There is no warning before it occurs, or ill effects after it ends, and has done it both stopped in traffic, and smooth cruising without hitting any bumps or jarring of any kind.

Sorry if this got longer than I meant- Anyone else have this happen or know what could cause it? Many thanks for info-

Brian in Las Vegas

[crazy steve]

If everything else works when it dies but the starter doesn't, then the problem is in your ignition circuit. If you still have the OEM fuse panel, look there first; these are known trouble spots, most owners replace the panels to use modern fuses. From there, the power goes to the 'kill' switch on the handlebar, another known trouble spot. These get corroded over time, disassembling/cleaning will generally fix it. If they're still in place, you also have 'safety interlocks' on the sidestand and transmission that prevent the starter from engaging if the stand is down or if the bike is in gear and the clutch isn't pulled in. Bad connections here can cause issues, but these won't kill the motor. The starter circuit is powered off the ignition circuit, so if you lose that the bike won't turn over.

I strongly suspect that your problem is either the kill switch or the plug where the handlebar controls plug into the main harness, probably the former.

[dpo]

Thanks-

I assumed it was likely the kill switch too, but since I never use the switch to turn the bike off it didn't seem it should be getting worn out.

[motoman]

I assumed it was likely the kill switch too, but since I never use the switch to turn the bike off it didn't seem it should be getting worn out.

Your kill switch is a definite suspect. It NEEDS to have contacts clean since it completes the running circuit. Remove it and take it apart, taking care not to have the tiny internal spring boing out somewhere in the man-cave. Take the switch itself and all internal pieces and soak them overnite in a shot-glass full of Evapor-Rust. rinse clean and blow dry every part, including switch itself. Re-assemble using a tad of dielectic grease and remount on handle bars. Also, the plug-in at top of frame under tank on right side is its connector. Unplug it and throughly clean those contacts and re-assemble. That is the easiest starting point. NOW check that voltage at that plug-in is same as batt. voltage, key on, batt. voltage needs to be the same at plug-in. If it is lower, your gonna have to check and clean ALL grounding locations. That'll be a good start and report back here to your findings........we can then steer you in correct direction for more checking. BTW, the kill switch completes the running circuit, as I'm sure you knew.

[hondakid11]

Ignition

have you checked the key switch? i had a problem with mine being gummed up with grease. once i cleaned that it worked fine.

[BA80]

Sounds like a fuse issue to me. Those old glass fuses will get hot on the metal ends because of a poor connection with the tabs in the fuse panel and the solder that holds the fuse link will melt and lose contact. The fuse looks good but it isn't making contact inside.

[Radioguylogs]

I just had an episode with an intermittent kill switch in my XS750SF a few weeks ago. It is the same switch and the same basic circuit as the XS11.

I checked the kill switch right way, and it didn't look bad.

I pulled the gas tank and found that round trip through the kill switch had obviously high resistance, 200k-1.2MOhm at the time I happened to measure.

I disassembled the switch, soaked the parts in carb cleaner, rinsed, dried, and reassembled them. Resistance went to 0.5 Ohm

FYI: I'm at work, so I didn't check the XS11 wiring, but I was able to rule out the IGN switch on the 750 by beeping the horn while the problem was occurring. Don't know if this applies to the XS11.

[Jerry]

The XJ has additional circuits that detect when the side stand is down and the clutch lever is not pulled in. What you are describing is typical of the side stand switch going bad. The switch is no longer available from Yamaha.

You can test this by following the cable from the switch up to a junction near the fuel tank. There are 3 wires in the cable. Unplug the cable at the junction and short all 3 wires on the bike side of the connector together. I made up a 3-way connector using 1/4 inch spade terminals to do this on my XJ.

If the problem disappears the side stand switch is bad. At this point you have three options: try to find a good used switch, leave the switch disconnected and the 3-way connector in place, or repair the switch.

If you try to repair the switch you will need to cut around, not through, the end of the switch where the wires come out. Clean up the guts of the switch and put it back together using something like JB Weld. There is very little clearance in the end of the switch and gunk gets in and prevents the plunger from seating correctly.

The clutch cable switch can also be checked by following the cable back to the bike, unplug at the connector and jump the bike-side connector (2 wire) which bypasses the switch. Again, if the problem goes away you have pinpointed the culprit. Last time I checked the clutch switch assembly was still available from Yamaha but it has been quite a while wince I checked.

The purpose of these interlocks was to prevent a person from riding off while the kickstand was down. It is one of the reasons the XJ's wiring is more complex than the XS and why an XJ specific manual is needed to help track down these problems.

In my case the kickstand switch was bad and I have since run with it disconnected and the 3-way connector in place near the fuel tank junction. This negates the safety interlock, though, and is not recommended.

Also, as it has been pointed out, if you are still running the OEM glass fuses the "fingers" that hold the fuses in place get brittle and fail. They look OK but are not. Replace the OEM fuse lock with a different unit; a search will turn up tips on how to do this.

Side stand switch failure is very common on the XJ and your description is very close to what I experienced with mine. Good luck hunting down the culprit.

[BA80]

I thought the side stand switch just kept the starter from working like the clutch lever switch, not kill the ignition all together.

[Schming]

If the side stand, on the XJ, is put down while running in gear it will kill the engine.
The XJ will only start in nuetral, so if you stall at a light, whilst starting out, with cars behind it makes it pretty interesting to find nuetral