weird event riding to work this morning.

superdiver · Sep 8, 2014

So on my 10 mile commute this morning about 3 miles into it i was traveling at 50ish, just cruising in, not changing gears, not shifting not accelerating or decelerating nor braking or touching the clutch or front break. LITERALLY just sitting there cruising....

All of the sudden my bike decelerates about as fast as when you turn the throttle all the way down without hitting any breaks, and ALL the dash board lights flash on for about 0.5 seconds and at the end of that the bike backfires once and then everything resumes to normal! literally, all in about 0.5-1.0 seconds.

Tank is about half ful, no electrical work done or messing with any engine things at all prior to this. it only happened the once on the ride into work and has not happened before... I am thinking its just a fluke gremlin, but I dont like them things! I always worry they are going to strike again, and NOT as I am pulling INTO my drive way...know what I mean?

970mike · Sep 8, 2014

I would take a look at all of your electrical connections and look for corrosion and or loose connections including the battery. That is where I would start.

Mark · Sep 8, 2014

Yup, I'd be checking the electric system, specifically the kill switch and the main bike electrical grounds.

Mcreviver · Sep 8, 2014

I would also check the main fuse for corrosion at the terminals. It's near the starter relay and has a red/white wire going to it.

v8-7 · Sep 8, 2014

And the ignition switch. Jiggle the key around while running

caldercay · Sep 8, 2014

and check under the seat to be sure none of the wiring harnesses has been rubbed through

superdiver · Sep 8, 2014

ok..wow... alot of stuff to check... will get on it...

anyone care to prioritize in order on a list? as to likely places to start?

Mark · Sep 8, 2014

With the bike running I'd wiggle wires first because it'll be the easiest!

Firstpeke · Sep 8, 2014

Battery terminals, both at the battery and at the frame and starter relay

Fuse in starter relay and all cables connected to it, note colours and locations on relay when removing plug as it may be corroded and require work!

Starter button and kill switch.....

Fuel filter and pump.... and vacuum shut off.

If you get this far and haven't found anything, I would be surprised.

stgolfer · Sep 8, 2014

That exactly describes what happened when I hit the kill switch accidentally on the highway, then flipped it back on.

dduelin · Sep 8, 2014

superdiver said:
So on my 10 mile commute this morning about 3 miles into it i was traveling at 50ish, just cruising in, not changing gears, not shifting not accelerating or decelerating nor braking or touching the clutch or front break. LITERALLY just sitting there cruising....

All of the sudden my bike decelerates about as fast as when you turn the throttle all the way down without hitting any breaks, and ALL the dash board lights flash on for about 0.5 seconds and at the end of that the bike backfires once and then everything resumes to normal! literally, all in about 0.5-1.0 seconds.

Tank is about half ful, no electrical work done or messing with any engine things at all prior to this. it only happened the once on the ride into work and has not happened before... I am thinking its just a fluke gremlin, but I dont like them things! I always worry they are going to strike again, and NOT as I am pulling INTO my drive way...know what I mean?

I would start troubleshooting by riding the bike and momentarily switching off and back on the ignition key switch then the same with the kill switch. One or the other should replicate the initial experience. The warning lights flashing tend to steer me toward a loose, broken, or corroded wire or fitting going open circuit or to ground in the primary ignition system or kill switch. If the fault is as far downstream as the battery or ignition switch everything would go dark when the fault occurred.

BudC · Sep 8, 2014

superdiver said:
So on my 10 mile commute this morning about 3 miles into it i was traveling at 50ish, just cruising in, not changing gears, not shifting not accelerating or decelerating nor braking or touching the clutch or front break. LITERALLY just sitting there cruising....

All of the sudden my bike decelerates about as fast as when you turn the throttle all the way down without hitting any breaks, and ALL the dash board lights flash on for about 0.5 seconds and at the end of that the bike backfires once and then everything resumes to normal! literally, all in about 0.5-1.0 seconds.

Tank is about half ful, no electrical work done or messing with any engine things at all prior to this. it only happened the once on the ride into work and has not happened before... I am thinking its just a fluke gremlin, but I dont like them things! I always worry they are going to strike again, and NOT as I am pulling INTO my drive way...know what I mean?

All of the suggestions are good, but I'll throw in something else to consider: a broken connection within what appears, externally, to be fine. If none of the other suggestions identify anything, look for something like a fuse with a hairline crack, or a wire with a break inside the insulation.

I upgraded to the 40A alt, and put in a lot of custom wiring, so I wound up with a non-standard main fuse. The case holding it cracked very slightly, so that sometimes it would make contact and sometimes it wouldn't. If the "wouldn't" occurred with the battery mostly discharged (as in "need new battery" + right after starting) I would see that exact same symptom.

v8-7 · Sep 8, 2014

I took that to mean the lights were off and then came back on ...

If the lights were never off, then Dave is correct.

superdiver said:
ALL the dash board lights flash on for about 0.5 seconds and at the end of that the bike backfires once and then everything resumes to normal

STurgisSTeele · Sep 8, 2014

Depending on what the lights did on the dash, you also might want to check that the side stand is staying all the way up. I had mine come down a couple of times one day. The first time was just a blip, maybe like what you experienced. The second time killed the bike at 70+ mph in traffic and I coasted to the shoulder. But I saw the side stand light up and stay on while riding. At the time I thought it was just weird. Later determined the side stand could come down just far enough to trigger the light, but not kill the engine.

Jim Van · Sep 9, 2014

Maybe the ignition module had a "Brain Fart" ??

superdiver · Sep 9, 2014

stgolfer said:
That exactly describes what happened when I hit the kill switch accidentally on the highway, then flipped it back on.

I dint notice if i did that, and I didnt purposefully turn it back on... i cold be that I just bumped it or that it is going bad?? of course as I age, unlike the rest of you I am sure, i miss alot of crap...LOL

superdiver · Sep 9, 2014

v8-7 said:
I took that to mean the lights were off and then came back on ...

If the lights were never off, then Dave is correct.

The dashboard lights were off (as is norm for my bike while under way, all but one on the right hand side, i dont remember what one it is... but either way), then they all flashed on for half a sec and they went off and back to normal...

superdiver · Sep 9, 2014

STurgisSTeele said:
Depending on what the lights did on the dash, you also might want to check that the side stand is staying all the way up. I had mine come down a couple of times one day. The first time was just a blip, maybe like what you experienced. The second time killed the bike at 70+ mph in traffic and I coasted to the shoulder. But I saw the side stand light up and stay on while riding. At the time I thought it was just weird. Later determined the side stand could come down just far enough to trigger the light, but not kill the engine.

OOOH OOH OOH... i bet this might be it.... it does the exact same thing when i put the kick stand down with it in gear! I wonder if i hit a bump just hard enough to bound the stand and trigger it, or if I bumped it with my foot OR OR OR the sensor is going bad on it???

Don B · Sep 9, 2014

Firstpeke said:
Battery terminals, both at the battery and at the frame and starter relay

Fuse in starter relay and all cables connected to it, note colours and locations on relay when removing plug as it may be corroded and require work!

Starter button and kill switch.....

Fuel filter and pump.... and vacuum shut off.

If you get this far and haven't found anything, I would be surprised.

These are all good troubleshooting hints for resolving some faults, but none of them fit the faults experienced by superdiver except a possible intermittent problem with the kill switch. My thoughts are that the suggestions posted by dduelin (post #11) pretty much hit the nail on the head. Regardless of the source of the problem, nailing down the culprit is going to be easier said than done, since the fault is obviously very intermittent, making any troubleshooting more challenging.

Don B · Sep 9, 2014

superdiver said:
The dashboard lights were off (as is norm for my bike while under way, all but one on the right hand side, i dont remember what one it is... but either way), then they all flashed on for half a sec and they went off and back to normal...

I don't recall offhand what the instrument panel looks like on the ST1100, but I would hope the dash light that was on was the high beam indicator (blue light if the same as on the ST1300). Anything else would most likely be a warning of some kind of problem, such as low oil pressure, etc.

weird event riding to work this morning.

superdiver

970mike

Mike Brown

Mark

Gotta make tracks

Mcreviver

v8-7

caldercay

superdiver

Mark

Gotta make tracks

Firstpeke

NT1100D

stgolfer

dduelin

Tune my heart to sing Thy grace

BudC

'91 ST STOC# 422

v8-7

STurgisSTeele

When did I become the "Old Man"!?

Jim Van

superdiver

superdiver

superdiver

Don B

Don B