[77GL1]

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Ok, long story, but I stripped my 77 GL of all wiring, and re-wired it from scratch like I've done with all my other bikes, everything’s workin’ great!!! I’ve put in Accel 3 ohm coils. At first I left in the factory ballast to keep the voltage down, but with out the bypass during startup….it’s real hard to start, if at all. I took the ballast out of line and it starts (faster than ever) easily and runs great (stock points for now). I am how ever concerned about overheating the coils.



These are 3 ohm coils, and I think they’re ok, but does anyone know what the ohm rating for the original coils and the ballast are?



Thanks!!

 

[englishted]

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Hi and welcome to the forum. According to my bike stats book, it's 2.6 ohms, + or - 0.3 at 20 degrees. Hope this helps.

 

[77GL1]

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I had forgotten I have a digital meter (as well as my cheap one) and came up with 2 on the coil and 3 on the ballast. That would make sense, considering the phone tech and Dyna said I should run 5 ohms. I'll measure the Accel coil to see what it actually is and decide what to do. If necessary, I can put in a relay off the solenoid to run 12v source to the coils (bypassing the ballast), and I wonder if I could run something directly off the starter switch, considering current only runs thru it when depressed.

Eh - a little more research and I'll know what I've got'a do. I just don't want the system the way it was stock. 'bout 20ft of wire the way honda did it.

 

[twisty]

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77GL1 wrote:

Ok, long story, but I stripped my 77 GL of all wiring, and re-wired it from scratch like I've done with all my other bikes, everything’s workin’ great!!! I’ve put in Accel 3 ohm coils. At first I left in the factory ballast to keep the voltage down, but with out the bypass during startup….it’s real hard to start, if at all. I took the ballast out of line and it starts (faster than ever) easily and runs great (stock points for now). I am how ever concerned about overheating the coils.



These are 3 ohm coils, and I think they’re ok, but does anyone know what the ohm rating for the original coils and the ballast are?

77GL1, I can't answer directly on your 77GL but have been working with auto ignition systems for over 45 years.

On most (points type) ignition systems I'm familiar with the coil resistance needs to be around 3-3.6 ohms for proper coil & point life. What that means is:A 3+ ohm coil can be used with NO added ballast resistor. Coils in the 1-2 ohm range need an external resistor (usually in the 1.4-1.8 ohm range) to allow total coil circuit primary resistance to be in the 3-3.5 ohm range.

The idea behind the 3 ohm primary is to keep the primary running current below 4.5 amps at idle. When the primary's current gets up in the 4.5-5 amp or higher range point life gets short & coil overheating becomes a problem.

Electronic ignition systems can handle higher switching loads due to transistor controlled switching so can use a lower resistance coil but that then demands a more robust coil with better windings & better internal cooling.

Twisty

 

[Frenchy]

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I'd upgrade the ignition.



My 76, & Susan's 77 (w/78 motor) both started harder when they had points. I put a dyna elctronic ignition on each, & they perform so well, I haven't given a coil upgrade a second thought.:cheeky1:

 

[axelwik]

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If your starter button is working properly, it will bypass the ballast resistor when the button is pressed to givethe coilsa full 12 volts. When you release the button the ballast resistor is back in line and the coils get about 7 or so volts (to extend the life of the points). If your battery is getting a little tired it could cause hard starting. Might want to check the condition of your battery.

My bike still has the points as well. It starts fine when it's cold, but sometimes takes a little cranking when it's warmed up. My next upgrade will probably be a Dyna ignition system.

 

[77GL1]

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axelwik wrote:

If your starter button is working properly, it will bypass the ballast resistor when the button is pressed to givethe coilsa full 12 volts. When you release the button the ballast resistor is back in line and the coils get about 7 or so volts

No, I got rid of all the extra wiring, intentionally....no more reserve lighting, no resistor, no diodes. I did leave the ballast because with 3 ohm Accel coils, the points burn, but the stock ballast without the bypass made it too hard or impossible to start. I ended up with a variable ballast that starts at .75 ohms and after hot, is 1.5. That puts my max (3.2+1.5) at 4.7.

I did all the because my wiring was bad and burned out my Dyna and 7vt. regulator, so I just got rid of everything I didn't want, and rewired it from scratch, my way, wire by wire. I will send the DynaS back for repair ($75). Until then I've got'a deal with the points. I'll probably wire in a jump wire across the ballast terminals to a button, so...for hot starting, I'll just push a button or toggle to jump across the ballast. It's goning to be another month or so before I send in the DynaS. Sure will be glad to get it back, but I've got'a make sure all the bugs are out before putting it back in.

 

[axelwik]

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77GL1 wrote:

No, I got rid of all the extra wiring, intentionally....no more reserve lighting, no resistor, no diodes.

Sounds like a whole new can of worms... good luck!

 

[77GL1]

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It's all done, I took it out again today at 3 to 4 pm at over 100 degrees on the freeway here in San Antonio. Everything works great. When this ballast is hot the 4.7 ohms (total with coil) makes starting a tad slower, but not a problem, and the points don't burn. The fan worked as usual, and the temp guage showed low to mid-standard range. The only thing left is I'll jump the ballast with a switch for hot starting, 'till I get my Dyna back from Dynatek.