Andrews coils

Just won a set of andrews ign coils (#6262B) on ebay. Found with help of friend (spokewheels650B) that they would work on my stock point system. However, I have read articles about certain aftermarket coils need to have the ballest resister bypassed for them to work. I'm a mechanic but do not do electrical. Is this true?, do I have a ballest resister? If I need to bypass it, how is it done and why? Thank you...

Post edited by: Bluemeanie, at: 2006/12/10 09:59

To figure out if you have an inline ballast resistor, check the path of power from your right hand switch gear to your coils. The ballast resistor will be inline with this path. Check a wiring diagram for the color of the wire coming out of your right hand switch gear.

To determine if you need to bypass a potential ballast resistor, measure the primary impedence of the coils you just bought. Do a search in this forum... I have explained how to do this numerous times. Your primary resistance should be between 3 and 4.5 Ohms at your coils. If you find that it is in this range, and you find a ballast resistor, inline with the power, you will need to splice the power wire in to the power wire out without going through the ballast resistor which will add impedence and drag your spark down. A ballast resistor will look like a 2 inch long white thing with the power wires attached. It is usually between the fork tubes up by the fork OR on the battery box somewhere.

Thanks WG, I'll check the coils and by-pass the resistor if need be. One last question... I was planning on doing your wiring mod to the coils. Does this still apply to these coils or is that just for stock coils? Thanks for your help...

Hey Blue, when I installed the Andrews coils in my '78 I didn't see any resistor inline with the system anywhere. I wanted to make sure I had a full 12v to the coils to get the best spark possible. Also, before I changed the coils over I had experienced a bit harder starting with the electric starter when cold (would crank for 5-10 sec before coming to life but when kickstarted it would lite first kick). After the coil switch it lites off MUCH quicker;) I was going to do the wiring mod before, no need now.
My Andrews coils ohm'd out at 3.5 to 4ohms, just right for points without a voltage dropping resistor.

merry Christmas!
Ray

SpokeWheel650B wrote:

...I was going to do the wiring mod before, no need now...

Just wanted to mention that I've done the relay-power coild mod both before and after installing a new coil (in my case, Dyna). It still made a difference either way for me, and I reccommend doing so....

As far as I know, the 1000's were the only ones with ballast resisters.

The WG relay mod is used to bypass the resistance due to bad connections/etc in the rest of the ignition supply wiring to deliver solid 12V+ to the coils.

Thanks guys, looked over the bike and the wiring diagram and no resistor was found. Spokewheels, you are describing the exact problem I've had for years. Engine would spin over with electric start but not start, one good kick and it would light off! Last month rebuilt carbs, new carb holders, new points,etc. Runs much smoother, but although it now starts with electric, it still spins awhile before starting. Looking forward to UPS box on my door step!! Thanks again guys

Andrews coils arrived today, and they both ohmed out at a perfect 3.1 each. Looking forward to swapping coils and seeing what the old 26yo, 48,000 mi, coils check out at. Will still do the coil mod, I'm a mechanic so I should have everything I need at the shop. Thanks for the help guys

Andrews coils arrived and installed. What a friggin difference!! Easier start, smoother idle, and greatly improved throttle response! Also, can now feel a power surge at about 7 grand which I never noticed before. Really curious what stock 26yo, 48k, coils ohm out at...

Bluemeanie wrote:

Andrews coils arrived and installed. What a friggin difference!! Easier start, smoother idle, and greatly improved throttle response! Also, can now feel a power surge at about 7 grand which I never noticed before. Really curious what stock 26yo, 48k, coils ohm out at...

did you decide to keep your points?
or go aftermarket elec. ignition?

Still have points, can't afford electronic now. But when I get the chance, you bet! Checked out my old coils and they were at 3.9-4.0 ohms, and from what I read in another post that can be a big difference! Plus the wires were hard as a rock so in the trash they go! The andrews coils are not only "fresher" but being high performance coils they put out a hotter spark than stock.

Post edited by: Bluemeanie, at: 2006/12/26 21:55

Good to hear they worked well for ya Blue;) I too am curious as to what trigger yer running...points or Dyna?
Hope everyone had a great Christmas!

regards,
Ray

(OOps, looks like you beat me to it Blue, points it is)

Post edited by: SpokeWheel650B, at: 2006/12/26 21:59