wrong coils!

[govburns]

So I was trying to figure out why I had a huge blue spark from my points and they were only lasting a week before burning up and melting... In my investigation I discover that the Accel 140404 coils, that were on my bike when I bought it, are 0.7 ohm!

I've ordered the correct 4 ohm coils for my 79 GS850GN (and another set of points) and hopefully I'll be up and running as soon as they get here.

I just needed to rant about it, because first I can't believe the PO made that mistake and 2nd that it took me this long to figure it out!

[BassCliff]

Hi,

I'm never going to sell my bike. There will never be another "previous owner" to blame for this GS850GT.


Thank you for your indulgence,

BassCliff

[Redman]

... In my investigation I discover that the Accel 140404 coils, that were on my bike when I bought it, are 0.7 ohm!

I've ordered the correct 4 ohm coils for my 79 GS850GN ..........
.....

Good.

Tell us, how did you figure that out?
Can the difference bee seen or just by measuring or by checking part numbers or something.

.

[govburns]

@Redman

I googled the Accel part number on the coils and found they were 0.7ohms in the specs on several sites. Then I measured them with my ohm meter to make sure.

I put two and two together, after reading in other posts that having coils with too low of a resistance forces the points to interrupt a bigger load, thus the big fat spark at the points.

[salty_monk]

Go to Radioshack, get some resistors.. solder them into the circuit & hey presto....

That's another alternative.

[govburns]

That's a really good point, I thought about that and it would definitely be cheaper, but the coils look pretty old and I'd just rather have the correct part.

Go to Radioshack, get some resistors.. solder them into the circuit & hey presto....

That's another alternative.

[Killer2600]

Go to Radioshack, get some resistors.. solder them into the circuit & hey presto....

That's another alternative.

And then you'll get a weaker spark that's assuming you get the right wattage resistors and don't burn them up

[salty_monk]

That's the whole point.... You want a weaker spark so it doesn't eat the points. It's the same if you buy 4 or 5 ohm ones off the shelf.

[Killer2600]

That's the whole point.... You want a weaker spark so it doesn't eat the points. It's the same if you buy 4 or 5 ohm ones off the shelf.

No no no, weaker spark at the spark plugs. Adding a 2 ohm resistor to a .7 ohm coil gives you 2.7 ohms in the system but only 3.11 volts out of 12 is used at the coil the other 8+ volts is spent at your added in resistors. How good a spark a .7 ohm coil will make with a mere 3.11 volts depends on design but I rather have 12 volts across my coil.

[govburns]

new coils came

My new stock 4 ohm coils came this afternoon and I just installed them with new points and gave her a tune up... Changed the whole character of the bike... so smooth now, especially at higher revs!

The fat blue spark at the points is gone and it was much easier to time cause the timing light wasn't jumping around all over the place.