xs1100 coils

[DEmily]

Hey everyone,

I am still working on this 79 xs1100. After unplugging the vent hoses for the bowls and syncing the carbs, she ran great for about a mile. It started floading again. Black smoke was rolling from the exhaust. After reading many post and running several test, I found one of the coils showing good readings on the primarys but zero on the secondarys. I pulled the plug wires from the coils and tested the wires themselves. They where fine. (I should mention I installed new wires in the coils as the post on this site instructed.) After checking the wires, I checked the primary contacts right on the coil and still had zero, no reading. I assume this coil has lost connection to the secondarys. I have not seen a posting showing these kind of results when testing these coils. Has anyone else every experienced the primarys reading good but the secondary terminals at the coil reading zero?

[TheDjost]

A reading of zero? Do you mean zero ohms, or zero continuity?
You mention no reading, so I assume no continuity. That means that the coils are broiken inside. They may "work" anyway, since they create enough voltage to jump the gap in the sparkplug. The spark may jump the gap in the wire inside the coil, but then you get a very weak and erratic spark.

Or maybe you are checking at the wrong terminals. (it's very unlikely that both coils went bad at the same time, so if both show bad...)

-Justin

[DEmily]

Justin,

Yes, I beleive the coils is busted inside. I was testing the secondary's . And I did not find two coils bad., just one. I just thought it was strange to not see this same kind of thing on previous postings. I have purchased Accel coils as replacement and will install them in the next few days.

Thanks

[TheDjost]

I hope it works out OK. Make sure you get rid of the ballast resistor when using aftermarket coils.

-Justin

[DEmily]

How much does the blast resistor add to the resitance?
The new coils are at 3 ohms, the manual calls for 1.5. How much would removing the blast resistor change my overall resistance? I would hate to toast my ignition box.

[DEmily]

Of course I meant to say ballast resistor. 16 hour day and I'm starting to go brain dead.....

[TheDjost]

The original coils are low impedence primary, and need less voltage to run. Around 9 - 10 volts. The ballast resistor drops the voltage to the requred level. The main reason for making a system like this, is that when cranking the starter, the voltage will drop a bit, and a 12 volt coil will loose power. If you use a 10 volt coil that has a ballast resistor, you can bypass the resistor and have 11ish volts at the coil during cranking to ensure a hot spark.

But new coils will deliver plenty spark even with the low voltages, so no problem during cranking, and they can withstand teh full 14 volts of the charging system.

Just get rid of the ballast resistor and connect the leadss together.

-Justin

[TopCatGr58]

From what I have been able to find and read on the NET regarding aftermarket coils for bikes, the only concern is for the newer machines running TRUE CDI type ignitions with coil resistance ratings around 0.7ohms!! Our ignition systems are much older, and a blurb in the Dennis Kirk catalog states that you can't hurt your ignition system if you use a coil that has a HIGHER ohm rating than the one you currently have!

Our Coil tech tips state for the Pre 81 bikes, you should run the Dyna Coils, cause they are rated for the 1.5 ohms, but the 81 and later bikes are rated at 3 ohms. A lower ohm rating would draw more amps thru it, ie. 12v/1.5ohm=8 amps, but a 3 ohm would only draw 4 amps. I've read that the balast resistor is designed to drop the voltage from 12 to around 9, which would also drop the amp draw/flow thru the coils to keep them from burning up. The resistor is bypassed during starting to provide a stronger spark when starting, but kicks in after the bike is running.

At 9 volts, the OEM's are drawing 6 amps, which is still 2 more than the 3ohm Accels without the balast resistor. And so theoretically there would still be 6 amps going to the TCI unit with the OEM setup, and only 4 amps with the after markets, so I can't see any concern running the Accels with the earlier models, just remove/bypass the balast resistor, and the TCI unit should still be happy, and the Accel's like the full 12 volts, so no worries about burning them up!!

Any electrical GURU's want to chime in!? T.C.

[young nip]

coils

Hi guys.
About the accel coils. I put a new set on my 79 last year.( dead secondary on old coil) I missed the ballst resister part info there. you mean the ballast resister thats on the bike attached to the frame?? Take that off and by pass it?I did notice mine needed a few more cranks and some throttle applied to start up. Does this ballst resister affect the starting amps. I didnt remove mine for fear of frying my igniton unit too. Just not sure if you mean a reisiter that may come with the accel coils or the stock ballast resister thats already on the bike. Electrical is definetly not my strong point. thanks guys.(snows melting yes yes !!!)
Steve

[randy]

Yes, the ballast resistor that is on the frame next to the left side coil. (the 1-4 coil). It's a little aluminum box with two wires coming out of it. IIRC Red / White. It is not needed with the Accel coils.

Left in place, the Ballast resistor will not have any effect on your cranking juice, because the resistor is bypassed by the starter solenoid during cranking. With the long crank time you may just be experiencing a weak battery.

Leaving the ballast resistor in place will, however have an overall effect on your coil voltage while running. The coil voltage will be reduced, so you will not be getting the full effect of the hotter spark you paid for and expected with the Accel coils. Remove the resistor, and solder the two leads together at the wiring harness.

You should feel the difference in performance if everything else is OK.

Randy

[DEmily]

Well, thanks for all the advice on the coils. I will be bypassing the ballast resistor. I am in the process of installing them as we speak. I'll let you all know how it goes.

[young nip]

coil follow up

Thanks Randy, top gator for the info. Djost too. Again this site has helped me with the little things. I havent had a real chnce to to work the new coils from last year. Just a bout 1500 K. I also had to go up 2 main jet sizes with the new pipes and the k+n filter too. I was lean.DEmily: youll have a small creative installation to get your accels on. I went thru last year with my bike acting up with a surge at 4200rpm. I had my carbs clean then found out I had a sticky advance mechanism then as the trouble persisted I finally had the coils tested. Dead secondary on one too.The glitch behaved more mechanical than electrical. who would think a coil would wear out. Last thing I ever thought of. But afetr doing all the other little maintenace things that I havent had to do all these years.( great reliable bike) ,the bike runs top notch. I look forward now to removing this resistor and find out if the bike will have even a slight more pop to it. It rained here all day in ontario guys. snows goin!!!!Just need them streets swept up and get the grit off the corners.pant pant.
Thanks again guys.
Steve

[DEmily]

Well, I got the new accel coils in with little effort. The spark is much stronger. I fired up the bike up and took her for a spin. Damn these bikes are fast!!! You all have been great help. But now I have a new problem that just pop up. After crusing for an haour or so I decided to head back. I pulled in the drive way and shut her down. I came back out about an hour later and started it up again, just to hear the old girl run and after about 10 minutes oil started running out of the left exhaust! Puzzled, I drove it down the street and back and it never missed a lick, yet it was still running oil out the left exhaust. What could this be? Valve seal, oil ring, what? It's running like a champ. I pulled the exhaust and it looks like number 1. I pulled the plugs and number 1 was slightly wet on top, but looked like it was burning good. I think I have gotten my self into a money pit. Compression is even at 130 across all cylinders. HELP!!!!

[skids]

Are you positive that it isn't just water that has run out of the pipes? You *might* want to screw the No. 1 pilot screw clockwise about a quarter to a half of a turn to lean it just a bit. Keep checking the oil and just ride that baby! 130 psi across the board is really good.

Originally posted by DEmily
What could this be? Valve seal, oil ring, what? It's running like a champ. I pulled the exhaust and it looks like number 1. I pulled the plugs and number 1 was slightly wet on top, but looked like it was burning good. I think I have gotten my self into a money pit. Compression is even at 130 across all cylinders. HELP!!!!

[DEmily]

Skids,

No it is oil. I am talking running out of the exhaust. If the oil ring was letting oil by I would expect to se lots of oil smoke. What about the exhaust valve seal. Could that be leaking enough to cause the oil to blow out the exhaust but not really effect the engine performance?