No Spark??

[chopz54]

Having nearly completed my GS1100G, from a pile of parts to a Motorcyle, I now find I,m missing sparks on cyl- 2/3. I have done the following but still no luck. Swapped over coils + leads caps from 1/4 ( which sparks great and fires up ) No that.Checked p/up resistance 160ohms each, not that,cleaned/tested alll block connecter terminals in a out of IC box, not that,I am also getting power to both coils, Did get a spark on both coils last week...but whats changed? Hope its not the IC box, its the old tin box type. Have a Factory manual, but they are only as " refreshers " for deallers and dont really go into the real world of might and can happen. Any suggestions please??? Thanks Chopz54

[Dave8338]

No mention of new plugs...did you throw a set of new plugs in?

[Redman]

WHen troubleshooting ignition problems; Dont overlook the spark plug caps.

They do deteriate over time, have a resistor material in them that degrades over time and usage. Are about $5 each for NKG aftermartket. Twist/screw them off. Can test them with an ohm meter. 5000 ohms (5K) I think. They go to way high reistance near infinity (open) when they fail.

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[chopz54]

No mention of new plugs...did you throw a set of new plugs in?

Yes have a new set of ngk's, as mentioned above 2/3 cyl- coils/plugs/caps have been interchanged with 1/4 with the bike running fine on 1/4 cyl- Any further suggestions please??? Have noticed that a lot of the GS's share the same timeing would it be possible to fit a set of points/con's/a-retard from (for instance ) a Gs1000/750/850 etc ??As the mounting holes look the same a I,m sure would be plenty of room?? lashing out £100 ($200) for a replacement e/ignition is not an option at the moment ( dont think they do have them here in England,for this model anyway).Also would an I-C box of a GS850 work on a GS1100 ? As theres a few of these about over here ( somewhere ?) But the GS1100G,s are pretty rare in England...well at least round my way anyway . Desperate to got out there on the road, and this is all thats stopping me !! Thanks Chopz54 ( England)

[psyguy]

all big gs fours after '80 use the same coils and the same igniters, i think
in 82 however the ignition advance was changed from mech to elec so theres two extra wires comming into the igniter box

[bmac]

Cdi

You are correct guy, 82 and up are different, 850 and up are the same unit. Got very lucky and found a cdi last month for my 82 850 for $50 here in the states. Timing is everything!!!!!!!!!!!!!!


bmac

[chopz54]

all big gs fours after '80 use the same coils and the same igniters, i think
in 82 however the ignition advance was changed from mech to elec so theres two extra wires comming into the igniter box

Mines an 82, with 2 block conn- 1 has the blue,green,black & yellow for the p/up ( 2 for each one ), the other has 4 wires black-white ( earth )
orange-white ( coil - cut out switch ) white ( coil ) black-yellow ( coil ).
the problem being with that black-yellow wire.

[psyguy]

sounds like a faulty cdi unit

i'm not familiar with the internals of the "black box" so not sure if it can be repaired
they dont seem to fail that often so getting a used one ('82 or up) should see you right