Question for wiredgeorge

Im trying to check everything to make sure my bike is running its best. I have seen you talk about the coil power mod and read up on your website about it. I checked mine and here is what I got. Bike not running, key on, battery voltage is 11.98, measured 11.34 at the coils. So there is a voltage drop from bat to coil, but is it enough that I would benefit from your mod? If so I would have no problem doing it, and will go pick up the parts.

The coils work like this... two windings... primary and seconary. The primary windings are what get the power then the power goes to the secondary windings where it is discharged (spark). Since the primary voltage is multiplied by a factor of thousands, the secondary or the spark will be about 95 percent what it would be if you used the coil repowering mod. Is that signicant? Only sure way to know is to try the mod. It sort of depends on the health of state of tune of the bike and the health of the ignition system components.

I think I will go ahead and do the mod. I am an electronic technician by trade, and the more I think about it, the more I think it is a good idea. If I was dropping .7v at no load, it would be worse when the bike is running. Simple electronic thoery is that the voltage drop across a resistor goes up when current goes up, so I may be dropping 1V or better when under load. The parts are cheap anyhow, so I will do it this weekend and hopefully will have good results.

you can try it out with just one wire, make it connect to the coil power terminals and the battery. if it gives you joy you can hook up the relay, etc.

Oh, You still might want to use the FUSE with that test wire.

And don't forget to unhook it when you park.
:lol:

Thats actually what I was planning. Run a wire straight to the coil and fire it up. If there is a noticable change, then go ahead and put in the relay and make it permanent.

I was like you - with engine not running I had 12.3V at the battery and 11.8V at the coils. I went ahead and did the mod and am delighted with the results. The bike runs noticeably better under 4,000rpm and the plugs which were always a tad on the sooty side are now looking much like they should.
see kzrider.com/component/option,com_joomlab...id,4/id,53755/#53755

Like you said - parts are cheap and you have nothing to lose.

Post edited by: JR, at: 2006/09/02 10:32

Thanks JR. That gives me a lot more hope of positive results since mine is worse than yours to start. Waiting for the weather to clear up to give it a go. We have whats left of the tropical storm comming across us and it's been nasty out since yesterday morning. Going to get my parts today and wire it up tomorrow. I will report back my results.

The coil mod is gonna be my Saturday project.

The bike has always seemed to be running very rich, always thought it to be the carbs set too rich. Black spark plugs. It doesn't want to make power from a stop, making the clutch/throttle very tricky...makes me look like an idiot trying to take off smoothly
Feels like the engine bogs down when cruising at steady throttle with less than about 3500 rpm. Once you get above that rpm it runs like a champ.

Anyway, checked my voltage at the coils (key on, engine off) had approx 9.5 volts. I will post the results once I finish the mod.

Holy Kaw! Only 9.5V at the coils? Something's wrong. Maybe some corrosion in the Y connectors?
What is the voltage at the battery?

spec4f150 wrote:

The coil mod is gonna be my Saturday project.

The bike has always seemed to be running very rich, always thought it to be the carbs set too rich. Black spark plugs. It doesn't want to make power from a stop, making the clutch/throttle very tricky...makes me look like an idiot trying to take off smoothly
Feels like the engine bogs down when cruising at steady throttle with less than about 3500 rpm. Once you get above that rpm it runs like a champ.

Anyway, checked my voltage at the coils (key on, engine off) had approx 9.5 volts. I will post the results once I finish the mod.

Yep, only 9.4 at the coils. 12.2 at the battery.

Anyway finished the rewire on Sunday, cleaned the plugs at the same time. Only drop .3V from the battery to the coils now. The relay cost a whopping $3.99. The first time I rode it man what a difference, smooth take-offs from a stop. Nice even throttle response, even when the engine was loaded down at a low RPM and high gear. Thought is was nice enough running to take it to work....whoops, got halfway to work when i fouled a plug, limped it home. Anyway to make a long story short, spent the rest of this week adjusting the fuel/air mixture on the carbs, and actually getting good results. Managed to at least get rid of the black/wet plugs, and was at the stage of just black fluffy till today. Now I'm starting to see some nice brownish color on the plugs. Maybe by next weekend I'll be able to back down off the hotter plugs

To sumarize, the coil mod was worth it! Now I that I can see a light at the end of the tunnel, I can start getting the carbs tuned correctly....Thanks wiredgeorge

BTW, vegas, yes there is some serious corrosion in the electrical system, only had 8V at the rear brake light. I lost about .8V through the fuse box. I think it is just a combination of a medium loss at every connection adding up to very big voltage drop. I was measuring with my negative on both the connectors and at the battery, so it's not in the ground line at least. I think this is just gonna be a splice at a time to correct.

Post edited by: spec4f150, at: 2006/09/15 21:36

Jeff, Go to a place where they sell computer supplies and buy a can of contact cleaner. Open all the connectors on the bike and spray them with contact cleaner... you may need to use a toothbrush on them if they have a lot of white scaley crud and repeat the cleaning. Once they get cleaned, get a tube of dielectic grease and coat all the connectors. Coat the connectors on the coil relay as well. This keeps the corrosion from reappearing.