Bike diag, no sprk from coil....

This is my 1st post in here.

anybody with any knowledge of cars or bikes will be able to assist here im sure

i have a spark problem, im not getting any

who wants to chime in

More info?

Bike I assume. Type?

Is anything else powering up? Is it cranking slow?

Any maint recently done?

92 gsx600f

its cranking over fine, all the fail safes are good (clutch safety, side stand switch, neutral,) even though those would typically prevent crank.

checked the winding resistances on primary and secondary at the coil, well within spec

checked resistance from the signal generator, also checks out.

as far as i can tell the cdi unit is fine, i just replaced it with a used one, but its doing the same thing. the 3 signal wires from the cdi unit are caring 12v to the coils, and as i just mentioned the coils primary and secondary winding resistances are within spec. what could i be over looking, i mean what else could cause the test plug from the coil to have no spark.

alright, well i got spark, and i heard her purring a little tonight, so i think i got this wrapped up, BUT

im going to do a little electrical diagnosing tomorrow to figure out exactly which wire causing the problem

i made my own harness from the cdi to the coils, and viola she started sparking, so i think its either the ground on the cdi, or 1 0f the 2 non common leads to the coils, like i said im going to look into to more tomorrow

coils grounded properly?

Crank trigger/relucter/magnets?

Ok so you got spark…where you getting it in the first place and assuming you weren’t?(I know your not dumb just asking), I was going to say check and make sure the kill switch isn’t faulty but your getting spark now. Condition of the plugs/wires? Whats your starting procedure? On a carb’d bike like this you may have to play with the throttle a bit…also check the choke cable and make sure its actually working…not warm enough yet for a carb’d bike to start without it. No backfiring when trying to start?

he has a spark problem, not a choke problem.

Chaz - check the resistance of the wires you replaced. Maybe an internally corroded or broken wire.

Broken wire was going to be my next suggestion.

thanks guys, its staring and running on its own power now, well with the choke on only… but at least itll run for extended periods of time. I am headed to check the resistances of the wires replaced, thats a damn fine idea. hope i fine the probin there, but so far i have found that this thing has a huge reading for resistance to ground all over, i think the main ground wire that daisy chains through out the bike is the faulty wire, and i hope so cause thats an easy fix

Thanks for the input guys, ill be posting picks soon, just didnt want a head bashing at the photos before i got it to run.

Now… anybody have a suggestion for getting the carbs close enough to take em for sync?

ground is very important in modern efi bikes. It may be just as important in your old carbed bike. It can’t hurt to have a good ground & I’m sure you have some wire layin’ around to do it.

See below :finger:

The sync tool is supposed to be available at Harbor Freight…its rather cheap and a good investment instead of paying someone else to do it. What happens when the choke is taken off? Die immediately? When you let it run for a bit with the choke on it should jump up in idle quite a bit…does it do this? And if so to about what RPM? Is there an idle adjustment cable on your bike(Mine has this…i don’t have to remove parts to access the carbs…its a little thumb turn button near my fuel on/off/reserve selector)?

And about the carb sync tool again…there are ways to make your own…and i know your crafty…but i would honestly just get the tool and be done with it

:finger: your still a tool.

haha you guys are nuts.

well it runs fine now after choking it for about 3-5 mins, im not sure where the idle adjustment is, but i have a tech from zanotti coming down to fine tune everything, just ordered the tires today should have it ready for state inspection by monday.

any suggestions on removing the tires myself so i can take em for powder coating?

they are a nasty purple, and since im putting new tires on it anyways i thought now would be a great time to do the wheels.

If you go to powder coat them you have to pull everything off including the wheel bearings and repack them with new ones. The heat will kill the bearings.