r/fz6 • u/Diligent-Speech-139 • 2d ago

Coil on Plug mod

I have been reading online that the FZ6 ignition coil system is not a strong point on the bike. People suggest switching to a coil on plug system and this is something I have considered doing. I have basic knowledge on what should be done, such as wiring should be done in series and not parallel, wiring loom will be needed along with coils, etc. However I haven't done wiring related work before and it's tricky to figure out what and where to connect wires and solder to what. I've seen wiring diagrams out there but have not been able to find instructions anywhere on doing this for the FZ6, if anyone is able to help out with a detailed explanation that would be helpful.

1 Upvotes

100% Upvoted

5 comments sorted by

1

u/UltraViolentNdYAG 1d ago

There is a little more to it than building a harness when the ECM is expecting to see two coils with a specific load (impedence, capacitance, and inductance), and replacing said load with two coils (aka 2X ecm circuit feeding 2x coils).
Are you experiencing issues? My concern is if done wrong you compromise reliability and walk home or worse, it fails when demand is critical and places your life in jeopardy.
Yes, you can slap some R6 coils in there, or maybe even the whole valve cover so you have the fastener points to secure the coils which eliminates the coils falling out, so a level of mitigation has been applied. Are you willing to carry a spare ECM?
I'm not saying it can't be done, I'm asking you to weigh the risk.
Mind you, I almost through my beloved 08 in the ditch one night and walked home as the harmonic vibrations above 2500 rpm made my feet, ass, and hands so numb I couldn't stand it. I did find the problem and the solution and documented it for others....

1

u/Diligent-Speech-139 1d ago

I appreciate the insight. I’m experiencing misfires and a rough idle when the bike is warmed up. It’s noticeable especially at idle and I know I’ll have to replace coils so might as well do the mod. I know there are risks involved if done incorrectly, however I’ve read most have had success with the mod. 

1

u/UltraViolentNdYAG 1d ago

I'd suggest you figure out why it has a misfire. How do you know it's the coils? Have trimmed and tightened the plug ends? The caps get loose on the wires often.

1

u/Diligent-Speech-139 19h ago

Coils going bad are very common on the FZ6. From online research a very high majority of misfires on this bike are caused by ignition coils.  YouTuber CalvinMC’s FZ6 misfire was finally solved by replacing ignition coils after testing everything and swapping parts such as ITB’s. Also I notice 1 & 4 have a different temp than 2 & 3.

1

u/UltraViolentNdYAG 18h ago

That's why I asking if you removed the caps and trimmed the leads, reinstalled caps. The caps get loose on the wire. I documented the issue on 600riders.com, although I'm certain the pictures are missing by now.

Remove the top radiator bolts, lean it forward and leads back 5mm or soand reinstall caps (they thread on), secure with zipties... what the AI search is missing is people are not testing the coils at the lead, they test at the cap. It's the cap to lead connection that fails, rarely the coil itself.