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weak spark-where to point fingers?
Posted: Sun May 18, 2008 6:08 pm
by megaloxana
So my bike has been plagued with a horrible weak spark problem which prevents it from starting. I tried two different fzr coils then installed the Ford coilpack in hopes of making this problem disappear but no luck so far.
What would make a my spark so weak if not the coils?
Im beginning to point my finger at the ignition box. Mainly because each cylinder has a different spark intensity.
I rated them the following on a scale from 1-10(10 being strong spark)
cylinder 1- (5)
cylinder 2- (3)
cylinder 3- (1)
cylinder 4- (1)
So anyway, what do you guys think is goin on here?
Re: weak spark-where to point fingers?
Posted: Sun May 18, 2008 6:30 pm
by bluetlr2001
Have you tired the plug wires. Take and test the resistance wire a volt meter from one end to the other if you havent replaced them yet.
Re: weak spark-where to point fingers?
Posted: Sun May 18, 2008 8:02 pm
by megaloxana
bluetlr2001 wrote:Have you tired the plug wires. Take and test the resistance wire a volt meter from one end to the other if you havent replaced them yet.
I didn't test them but I had tried 3 different plug wires in my venture. (two fzr wires and the set that came with the ford coilpack).
Re: weak spark-where to point fingers?
Posted: Sun May 18, 2008 8:56 pm
by haunter
i would def look at the ignitor next
Re: weak spark-where to point fingers?
Posted: Sun May 18, 2008 9:41 pm
by ragedigital
You know, people have reported that a bad kickstand switch can also be a culprit. I know it sounds crazy, but it's true.
I've simply disconnected my kickstand switch and jumped the 2 wires together.
I didn't have the spark problem, but the reduced weight savings from removing the kickstand switch helped me win a National Championship...
...kidding, of course.

Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 12:24 am
by megaloxana
ragedigital wrote:You know, people have reported that a bad kickstand switch can also be a culprit. I know it sounds crazy, but it's true.
I've simply disconnected my kickstand switch and jumped the 2 wires together.
I didn't have the spark problem, but the reduced weight savings from removing the kickstand switch helped me win a National Championship...
...kidding, of course.

well it does sound crazy but Ill give it a try. You would think that if the switch was the problem, the bike wouldn't turn over at all.
I'll post progress tomorrow.
P.S. anyone have a spare cdi they want to sell me?
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 9:24 am
by Modified96
Also check the Pick-Up coil in the stator assembly. If it is dirty, or off center, it will cause a weak/no start problem. The Pick-up coil is the device that tells the Igniter Box when to fire the cylinders. So if it can't read the magnets correctly it will cause problems.
Just take you stator cover off, then remove the stator and pick-up coil. Clean everything very well with some electrical cleaner and then put it all back together. Remember to use a little locktight on the bolts for the stator coil and pick-up. That might do the trick.
Hopefully it helps. Let use know what you find!
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 1:25 pm
by mpap
weak battery can cause weask spark do the tests in Electricians tool box, Check battery, VR, Stator. Keep us informed let us know your progress, I could always ride up and check it out for ya, try my cdi ect.. save ya some time and money before you buy parts you dont need.. these are all issues that can cause weak spark
Battery voltage low
Spark plug dirty, broken, or maladjusted
Spark plug cap or high tension wiring trouble
Spark plug cap shorted or not in good contact
Spark plug incorrect
igniter trouble
Pickup coil trouble
Ignition coil trouble
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 5:45 pm
by megaloxana
I checked the stator and pickup coil. Everything was pretty clean. I did the resistence checks on the pickup coil as suggested by the Haynes repair manual and it checked ok. The battery was geting a little low so I hooked up my car battery to it but that didn't make any difference in the spark. I also tried disconnecting the kickstand switch and jumping the harness plug but they didn't make any difference either.
mpap- I appreciate the offer to ride down. I'd imagine the ride from lancaster to hanover is still a decent ride and I would feel bad.
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 6:25 pm
by mpap
I have been to Ray Wilt not too bad I am always down to ride so Hanover just gives me a destination to ride to, If ya need or want the help I am more than willing to....
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 6:37 pm
by yamaha_george
megaloxana wrote:So my bike has been plagued with a horrible weak spark problem which prevents it from starting. I tried two different fzr coils then installed the Ford coilpack in hopes of making this problem disappear but no luck so far.
What would make a my spark so weak if not the coils?
Im beginning to point my finger at the ignition box. Mainly because each cylinder has a different spark intensity.
I rated them the following on a scale from 1-10(10 being strong spark)
cylinder 1- (5)
cylinder 2- (3)
cylinder 3- (1)
cylinder 4- (1)
So anyway, what do you guys think is goin on here?
Hi,
Ok so you put a new set of HT leads, changed the coils, checked the stator assembly, bridged the side stand switch, checked the battery still no joy. The only thing left is your CDI / igniter box in theory.
Before I went out to buy one I would have every connector in the ignition system apart cleaned and greased with dialectric grease (anti-corrosive / water proof BUT conductive. I would while it was apart check for "leaks" to ground and I would check the grounds on the coils FIRST as corrosion / poor contact on those will give you hell at some point
HTH
Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 7:20 pm
by megaloxana
OK....so i dont know if this was stupid or what but I now have good spark on all 4 cylinders. My problem was that I only have 1 spark plug plugged into the coil at a time. When I put a spark plug in each plug wire and grounded them, they all showed strong blue spark.
Thanks to all of you who helped out.
...Now its time for a little bunny dance

Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 7:22 pm
by mpap
Glad you got it figured out...

Re: weak spark-where to point fingers?
Posted: Mon May 19, 2008 7:54 pm
by Modified96
Haha, fun stuff!
Good to hear it is running!
Re: weak spark-where to point fingers?
Posted: Tue May 20, 2008 5:04 am
by yamaha_george
megaloxana wrote:OK....so i dont know if this was stupid or what but I now have good spark on all 4 cylinders. My problem was that I only have 1 spark plug plugged into the coil at a time. When I put a spark plug in each plug wire and grounded them, they all showed strong blue spark.
Thanks to all of you who helped out.
...Now its time for a little bunny dance

Mega,
Thank you for that now we know that the CDI MAY have a protection circuit in it that stops all the juice going to only one plug if that is all that is connected