no spark on my GS550

[Happyfeatherz]

I have a GS550 turns over fine , no spark to the spark plugs from the coil . took test light both wires to the back of coil has juice to them . anyone have any ideas

[Nessism]

What year is the bike? 550 had points early on and moved to CDI in '80 (I think). If you have CDI it could be the ignitor.

[brveagle]

if >80, then it's the ignitor

[SPARKSS]

I have a GS550 turns over fine , no spark to the spark plugs from the coil . took test light both wires to the back of coil has juice to them . anyone have any ideas

Do you mean that you have no spark output from both coils or just one? When using a test light to check the primary power supply to an ignition coil (in almost all cases) one side should show steady voltage key on whether cranking or not and the other side may show steady voltage key on but will flicker on and off as the engine is cranked. This indicates that the coils are being switched by either mechanical points or an electronic circuit (ignitor). If you have steady supply side voltage, but no switching, check that same wirirng right at the points or as close to the ignitor as possible for switching (this checks the wiring and narrows the problem to it or the switching device). If points, then check them for a moveable contact that is isolated from ground, and that the fixed contact IS grounded. IF the moveable contact measures grounded when open, disconnect the condenser associated and recheck (it may be shorted). If your system uses an electronic ignition (Ignitor), make sure the ignitor has a power supply and ground when the key is on (countless electronic assemblies have been replaced for basic misdiagnosis like this!).

If your system is an ignitor type, then you'll a little further info at this point (you should have a service manual.....if you don't have, get one).

IF INITIALLY you DID FIND SWITCHING occurring but still have no spark, check the spark plug wires and boots themselves and the plugs.......chances are though that you won't have 4 of these bad enough to not have spark of some sort on at least one.

Hope this gets you started, or at least doesn't hinder you

[Happyfeatherz]

what it is with key on both prongs at the coil where the wires clip on have a steady power , The bike is an 1985 GS550 and both have it . I really wanta thank you all for your help , I can't wait to get it running , It's a great bike and has only 6581 miles on it.

[humblepie]

where should the CDI box be?