ST1100 No spark!

Sure that the KILL switch is in the ON position? (or impaired)

Till '95 all ST1100's would actually crank but not fire with that switch off; BTDT with my prev '92 ... :cool:
They altered the wiring '96 onward so also the starter wouldn't get energized, hence at least an indication to the operator that something is off... ;)
 
Sure that the KILL switch is in the ON position? (or impaired)

Till '95 all ST1100's would actually crank but not fire with that switch off; BTDT with my prev '92 ... :cool:
They altered the wiring '96 onward so also the starter wouldn't get energized, hence at least an indication to the operator that something is off... ;)

Oh man, that's something I would do Hahaha! and I wish it was that simple! You are right though it does crank with the switch in the off position same as my goldwing. Crossing my fingers its the pulse generator and I can just swap it out! Thanks for posting!
 
... I wish it was that simple!
I'd still check that kill switch circuit...
I was confronted with a '91 ST1100 once, who's PO had compromised that wiring (some DIY de-mobilizer hidden under the handlebar covers), causing corrosion, hence intermittent failure...
 
I think if you don’t find a blown fuse or anything obvious, I’d blow it out some more, leave the farings off and park it in the sun. If you’re lucky, something just needs to dry out. I always start my bike immediately after washing (never using a pressure washer) and let it fully warm until the fan come on.
As a side note the ST has two coils not four. They fire every crank revolution for two cylinders. Each of the paired cylinders alternate between compression and exhaust, so there is a “waste” spark, if you will, for the cylinder on the exhaust stoke.
 
Good news! We found a broken wire in the pulse generator. Pulled it out soldered it up and bike fired up and started purring like a kitten!! Thanks a lot for all the suggestions guys!
 

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Good Catch! BTW, did you find those pesky bolts up near the headlight on the upper fairings? :biggrin:
Yes, never would have found those if you didn't tell me..hahaha! They were buried in there!
I can't believe how many parts, screws and bolts there are! I hope I can remember where everything goes! Thanks again!
 
Once you get those two 'hidden' bolts out of the way, you can pretty much strip the ST1100 down to the tailpiece with a 10mm wrench (needed for the upper fairing headlight bolts, mirror bolts and lower tank shelter bolts), a 5mm T-handle and a JIS screwdriver. ;)
 
Good news! We found a broken wire in the pulse generator. Pulled it out soldered it up and bike fired up and started purring like a kitten!! Thanks a lot for all the suggestions guys!

Where was this located? I need a manual. I have the same issue and I’m supposed to go ride In 9days!!
 
Check the ECM / Control Module. They drive the signals to the coils and, I believe, are the next common point upstream.
 
Check the ECM / Control Module. They drive the signals to the coils and, I believe, are the next common point upstream.

I have no manual. Any way to describe where it’s at?
Also took the plugs out and I don’t seem to be getting spark in any cylinder that’s what lead me here. Pulse generator or the control module(both of which I can’t seem to locate)
 
The Pulse generator is located under the fuel tank behind the engine. I would not take anything apart until you run the electrical diagnostic tests listed in the service manual. Another thing to think about is all the various safety switches that will prevent ignition. Tip over sensor, neutral switch, kill switch etc. Its very time consuming but you have to verify these are all working correctly before changing any parts. Best of luck to you.

I have no manual. Any way to describe where it’s at?
Also took the plugs out and I don’t seem to be getting spark in any cylinder that’s what lead me here. Pulse generator or the control module(both of which I can’t seem to locate)
 
A number of years ago I found a pulse generator cover oil seep. Have never heard of another occurrence, BTW. Hope these images help.

John

9E7C5F41-95D6-43AC-BC2C-D58970D45CAC.jpeg

E8727C5C-2542-4617-96A2-923A2BB35377.jpeg
 
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