Topic: CB550K Ignition Coils

[swestleyj60]

So, I'm replacing the coils and spark plug wires on my 78 CB550K project, in an effort to install a Dyna-S electronic ignition. Today, I read through my Clymer manual, as well as the instructions for the new 5ohm coils, and the instructions say that I should "bypass the ballast resistor between the coils when a Dyna-S ignition is used".

Honestly, I get what a ballast resistor is for, and that it's basically to step the voltage down, once the engine is running, so there will be less wear and tear on ignition components. However, I can't find it on my CB550.

I removed the old 3ohm coils and carefully installed the new 5ohm units, as per the instructions.  I built 4 new NGK spark plug wires and installed those as well.  Then, I tested each cylinder for spark, so I could be sure I got everything installed properly before moving on to the Dyna-S ignition plate.

Shouldn't there be a ballast resistor right next to the original coil pack...? Isn't it like a rectangular ceramic thing...? Am I looking in the completely wrong place...?

I haven't yet installed the Dyna-S. Before I went too much further, I wanted to make sure I had this resistor thing figured out, so I thought I'd ask y'all first.

Where, oh where has my ballast resistor gone...?

I don't see it in any of my exploded parts diagrams, nor can I seem to find any images of it anyplace.  Perhaps my 1978 550K didn't have one to begin with...?

[HondaMan]

There's no ballast resistor on these bikes. Only the Gold Wings of the 1978-80 era had them with points.
This is just another example of Dyna's poor instructions, IMHO...

A word to the wise: it is smart that you are installing the 5-ohm coils, but consider also unplugging the front running lamps in the front turn signals to try to improve on the charging problems you are about to encounter. The Dyna S will eat every last bit of power the 550 can generate, because it uses 1.5 amps more power than points, which essentially leaves you with 0.2 amp battery-charge capability at 4000+ RPM. That's all. Installing the Dyna S on any CB500/550/400/250F ensures it will always suffer a chronically low battery charge, unless the bike is ridden 75% or more on the hiway.

[swestleyj60]

A word to the wise: it is smart that you are installing the 5-ohm coils, but consider also unplugging the front running lamps in the front turn signals to try to improve on the charging problems you are about to encounter. The Dyna S will eat every last bit of power the 550 can generate, because it uses 1.5 amps more power than points, which essentially leaves you with 0.2 amp battery-charge capability at 4000+ RPM. That's all. Installing the Dyna S on any CB500/550/400/250F ensures it will always suffer a chronically low battery charge, unless the bike is ridden 75% or more on the hiway.

I can't thank you enough for the sage advice.  I'll unclip the front running lights before I install the Dyna-S this evening, as I'm going to be doing most of my riding on roads other than highways.

[swestleyj60]

Also...?  For what it's worth, I've ordered 1157/1156 LED bulbs for the tail light as well, so that should give me a head-start on keeping up with any charging issues that the Dyna-S creates...

[Bankerdanny]

I put LED's in my front lights, tail light, and gauges and also switched my headlight to LED. All together I think I spent about $140, but I spend a fair amount of time in city traffic and wanted to reduce the draw as much as I could.

[Deltarider]

All together I think I spent about $140

Good lord, that's a lot of dough! I don't like leds for indicators and brakelights. I've noticed they draw less attention. They are less lively. No glow on, glow off and one could comment: Led is dead. Carmaker Audi realised this also and they choose this solution to make indicators livelier and better noticed. Difficult to realise on a bike however.

[swestleyj60]

I got the Dyna-S installed and timed last night and everything went perfectly.  While I was at it though, I took HondaMan's suggestion and unplugged the front marker running lights so that they're now just blinkers (or "winkers" as the manual calls them).  Also ordered an LED tail light, so hopefully those two things will keep me on the correct side of the Dyna's increased power draw.

[HondaMan]

Also...?  For what it's worth, I've ordered 1157/1156 LED bulbs for the tail light as well, so that should give me a head-start on keeping up with any charging issues that the Dyna-S creates...

If you can find one, use the #1034 bulb in the taillight instead. The #1157 bulbs we are getting from China these days draw almost 200% of the current they should (actual test on Sylvania #1157 bulbs I bought locally, and also some "brand X" bulbs from Wallymart). In your case, you could use one of the turn signal bulbs: they are #1034 type.

[TwoTired]

I was thinking the same thing Hondaman.  But then I noticed he said 1157 LED substitutes.

No way to know how the LED is wired or resistors in circuit without one in hand.

Cheers,

[HondaMan]

I was thinking the same thing Hondaman.  But then I noticed he said 1157 LED substitutes.

No way to know how the LED is wired or resistors in circuit without one in hand.

Cheers,

Oops!
I missed that line!