replacement coils?

[Session101]

anyone here know a good place or have a good experience with coils?

i see these from motoelektrik
http://www.motoelekt.com/ignition.htm
but i think someone can do better than $125 for 2 6v coils

[nhmaf]

Highly recommend that you get the Dyna dual-coil units from Motorrad-Elektrik for $95, on that same page... either the "green" coil if you are running points ignition, or the "brown" coil if you are running the electronic ICU.   Quite a number of us have upgraded to these - they are smaller, lighter, very high quality and last a very, very long time.

Rick is a good guy, though sometimes hard to get on the telephone.   I have a "brown" coil on my R65LS, and when time comes to replace the coils on my R100, I will be getting one for it - it has been udpated to the Dyna III ignition..

[Bob_Roller]

If you do go with th Motorrad Elektrik Dyna dual output single coil, ask Rick Jones what method he recommends to mount the coil .

Also, the main ground for the '78-'80 model year bikes, is the forward coil mount, it's not too uncommon to have the bracket crack and cause odd erratic electrical problems .

Might not be a bad time to add a large diameter (10ga) from the ground harness, back to the battery .

[Barry]

$125 does seem excessive for a pair of 6 volt coils.  If you really want that type of coil one of the VW aircooled suppliers may have them for less.  

No reason you shouldn't use the dual output 3 ohm Green dyna coil which has a great reputation and for me the reduction in weight would be plus point. Those 6 volt coils are surprisingly heavy.

[Session101]

well i plan to stick with points, but all i need is ONE dual output coil? is there a writeup on how that works or the install? i don't see how that works... don't you need a second coil for the 2nd cylinder or else it will fire at the same time as the 1st?

[montmil]

Rick at Motorrad Elektrik includes a clear instruction sheet and mounting hardware with the Dyna coils. Install is quite easy.

The Airhead ignition design has a "wasted spark" that fires the plug on the cylinder that is going through the exhaust cycle. I believe this is true with both points and electronic ignition systems. Somebody will sing out if I'm mistaken about the points bikes.

I run the Dyna "brown" coil on both my R65s and have been very pleased with the zero problems and its good performance.

Catch Rick as soon as you can. I know he will be at the Barber/AHRMA event 11-14 October. I see him there at Airhead central.

[Barry]

The Airhead ignition design has a "wasted spark" that fires the plug on the cylinder that is going through the exhaust cycle. I believe this is true with both points and electronic ignition systems. Somebody will sing out if I'm mistaken about the points bikes.

No difference with the points bikes which is also a wasted spark system. Even though it has 2 coils they both fire at the same time because they are connected in series. A twin cylinder engine would need a set of points for each cylinder for it not to be wasted spark.

You only need one dual output green Dyna coil and it will work fine.

The wiring is simple.  Look at your twin coils and remove/discard the black/yellow wire that links #1 on the rear coil with #15 on the front coil. Now take the remaining Green/blue wire that goes to #15 on the rear coil and put that on one side of your Dyna coil (This is your +12V feed). There will still be 2 black wires on #1 of the front coil (one goes to the points and the other to the Tacho)  connect both of them to the other side of the Dyna coil. Don't worry about polarity on the dual ouput Dyna coils as it makes no practical difference.  Job done.  

Edit: Diagram of your existing twin coil set up added for clarity.

[Danie]

My R65's original coil has been replaced at least 6 years ago, with a coil which came from a Honda CD 200.

I use the R65 for dayly commuting, 48 kms per day, 5 days per week, and the Honda coil has never let me down.

[Session101]

The Airhead ignition design has a "wasted spark" that fires the plug on the cylinder that is going through the exhaust cycle. I believe this is true with both points and electronic ignition systems. Somebody will sing out if I'm mistaken about the points bikes.

No difference with the points bikes which is also a wasted spark system. Even though it has 2 coils they both fire at the same time because they are connected in series. A twin cylinder engine would need a set of points for each cylinder for it not to be wasted spark.

You only need one dual output green Dyna coil and it will work fine.

The wiring is simple.  Look at your twin coils and remove/discard the black/yellow wire that links #1 on the rear coil with #15 on the front coil. Now take the remaining Green/blue wire that goes to #15 on the rear coil and put that on one side of your Dyna coil (This is your +12V feed). There will still be 2 black wires on #1 of the front coil (one goes to the points and the other to the Tacho)  connect both of them to the other side of the Dyna coil. Don't worry about polarity on the dual ouput Dyna coils as it makes no practical difference.  Job done.  

Edit: Diagram of your existing twin coil set up added for clarity.

thanks barry, that's awesome, i think im going to order one now!

[jg928s4]

bought a 6v from NAPA for $15, it worked as a fine replacement for one I thought was bad.  Ended up being my bean can.

[Barry]

Dyna are quality coils and probably the best choice but a coil is a coil and for points bikes just about any dual output coil that was originally designed for use with points ignition should work. Points don't like switching much more than 4 amps so the primary resistance shouldn't be less than 3 ohms or for two 6volt coils 1.5 ohms each.

The cheapest dual output coils are the pattern ones for 70's Honda's. They can be found new for £25 - £30 but a mounting bracket would be needed and the bullet connectors will need replacing with spades.   Again you can forget polarity on dual output coils so no worries about terminal markings.