Author Topic: Resistors for 3-ohm coils! (Read 40604 times)

Bido · « **Reply #50 on:** February 22, 2008, 11:56:08 AM »

I have read this thread several times and a lot of it is over my head. I have a 78 F3 750 stock except for Dyna S, Kerker Headers with 2" comp baffle and K&N air filter with stock air box. The bike runs pretty good although acceleration seems a bit flat, may be the jetting 112.5 mains. I was looking into the 3-ohm coils to improve performance after reading this thread am I to understand that the improvement would not be that significant and by using the resistor on the stock coils I may see an improvement not much different than the 3 ohm coils.

Very confused
Bido

HondaMan · « **Reply #51 on:** February 22, 2008, 07:30:31 PM »

Quote from: Bido on February 22, 2008, 11:56:08 AM

I have read this thread several times and a lot of it is over my head. I have a 78 F3 750 stock except for Dyna S, Kerker Headers with 2" comp baffle and K&N air filter with stock air box. The bike runs pretty good although acceleration seems a bit flat, may be the jetting 112.5 mains. I was looking into the 3-ohm coils to improve performance after reading this thread am I to understand that the improvement would not be that significant and by using the resistor on the stock coils I may see an improvement not much different than the 3 ohm coils.

Very confused
Bido

Sorry if I've confused the issue: the resistors are only for the Dyna or Accel 3-ohm "high performance" coils. The resistors are not for use with stock coils.

In your situation, try looking into 115 mainjets with that combination of K&N filter and Kerker pipe. Also, try using the Nippon Denso sparkplugs, the X24ES-U (or XR24ES-U resistor type, if yours uses resistor plugs like DR8ES). The stock "D8" series plugs are a little cold for these engines, while the D7 series are a bit too warm. The ND plugs are right on the money, and have a U-shaped ground electrode which helps "spread the fire" with these turbulent-flow combustion chambers. You'll feel the difference immediately.

mattcoff1 · « **Reply #52 on:** February 25, 2008, 07:05:30 PM »

Thanks hondaman
Got the kit today,,,very neat very nice
Thanks
Matt

LMAERO_396 · « **Reply #53 on:** February 25, 2008, 08:49:09 PM »

Got mine today as well, look forward to hooking it up. Thanks Mark!

HondaMan · « **Reply #54 on:** February 26, 2008, 07:05:05 PM »

Thanks for the replies, guys!

78CB750CAFE · « **Reply #55 on:** February 27, 2008, 09:22:30 PM »

I got mine today, along with the Hondaman super duper ignition thingee

One small question on instalation,

The resistor pack has one bullet conector in for 12v, and the 2 spade connectors for out to the coils, right? OK, so I made some nice spade lug to ring connector jumpers for the coil (why not just make them with ring connectors because that is the hook up method on the Dynas?) now which lead do I use to feed the 12v to the resistor pack? The original 12v female on the Honda wiring harness or the Y connector from the transistor ignition box (my guess, but I want to be 100% sure)?

How helpfull is running a fresh higher guage wire from the handlebar switch? I figgure I might as well while I have the whole harness opened up to integrate the wiring from the ignition box.

Thanks,
Drew

HondaMan · « **Reply #56 on:** February 28, 2008, 06:58:58 PM »

Quote from: 78CB750CAFE on February 27, 2008, 09:22:30 PM

I got mine today, along with the Hondaman super duper ignition thingee

One small question on instalation,

The resistor pack has one bullet conector in for 12v, and the 2 spade connectors for out to the coils, right? OK, so I made some nice spade lug to ring connector jumpers for the coil (why not just make them with ring connectors because that is the hook up method on the Dynas?) now which lead do I use to feed the 12v to the resistor pack? The original 12v female on the Honda wiring harness or the Y connector from the transistor ignition box (my guess, but I want to be 100% sure)?

How helpfull is running a fresh higher guage wire from the handlebar switch? I figgure I might as well while I have the whole harness opened up to integrate the wiring from the ignition box.

Thanks,
Drew

Hmmmm...I put the flat females on the resistors because that's all I ever saw on the Dyna 3-ohm coils. So,...what size is the screw on the coils you have?

This is news to me...

The bike's wiring harness will have 2 black-white wire positions on the black-white wire, at the coils, from the KILL switch. Unplug the coils from the black-white, plug in the Ignition's black wire there. Plug the resistor's center wire into the other black-white "hole". This will leave you with an extra connector on the Ignition's adapter there. Then plug the coils into the (new adapters you made) from the resistors.

If you (or a friend near you) are handy at soldering, you can try to remove the existing wires from the resistors and made a new wire with the ring terminal for each side. Don't stress the resistor's terminals too much, or they will break off, though. Solder well, and add some insulating tubing (like the heatshrink) over the junction so an accidental bend won't short out one side of the resistor to the bracket.

Running bigger wires, or fresh ones on these 30-year old harnesses, is always a good idea. I added a second 20 AWG wire from the fuse to the headlight, connected it with the original Black wire up there, and my headlight was immediately brighter. After that, running an additional Black-white (if I can find some) from the return point of the KILL switch in the headlight, back to the coils' junctions, is next on my agenda...when i gets warm enough to work on it...

78CB750CAFE · « **Reply #57 on:** February 28, 2008, 07:42:49 PM »

Mark, lets see if I got this straight now....

The resistor will plug into open female 12v black/white coil feed on the Honda wiring harness, as will the black from the ignition module. Then there will be a spare useless male bullet connector coming off the Y connect on the ignition units black wire, so I will remove the Y from the black ignition unit wire and just put a single male bullet on there instead. I am also going to just solder up fresh leads to the resistor unit since the female spade connector from the resistor broke off on one of the leads on my first time unplugging it ( yes, I grabbed the strain relief/rubber housing when I unplugged, not the wire and it still came apart) .

My Dynas are marked 2007 and have screw on terminals, I will check and see what size ring connector I used for them and let you know. I do vaguely remember one I had on an RD400 I used to have that had spade/bladed connectors, I don't know when they changed.

thanks again,
Drew

HondaMan · « **Reply #58 on:** February 28, 2008, 07:58:19 PM »

Quote from: 78CB750CAFE on February 28, 2008, 07:42:49 PM

Mark, lets see if I got this straight now....

The resistor will plug into open female 12v black/white coil feed on the Honda wiring harness, as will the black from the ignition module. Then there will be a spare useless male bullet connector coming off the Y connect on the ignition units black wire, so I will remove the Y from the black ignition unit wire and just put a single male bullet on there instead. I am also going to just solder up fresh leads to the resistor unit since the female spade connector from the resistor broke off on one of the leads on my first time unplugging it ( yes, I grabbed the strain relief/rubber housing when I unplugged, not the wire and it still came apart) .

My Dynas are marked 2007 and have screw on terminals, I will check and see what size ring connector I used for them and let you know. I do vaguely remember one I had on an RD400 I used to have that had spade/bladed connectors, I don't know when they changed.

thanks again,
Drew

Thanks for the advice: now, I'll have to ask everyone what connector they need.

Oh, well...
The wiring harness on the bike will have the female on the black-white from the KILL switch, so plug the Ignition's male into that. Then, plug the resistor male into the Ignition's female, and the Honda harness will have a spare female left over (because you would have unplugged 2 coils from it). No need to cut off anything. You can, if you desire: it's just set up so nothing like that needs to be done (Plug-n-Play, you know...). Most riders don't seem to have the tools for this sort of work.

This "falling apart" business of the female connectors is distressing: these are T&B ferrules, normally very strong when crimped with their own tool (I must've done thousands, by now). Did the wire pull out of the crimped barrel, or did the wire break off, leaving the end inside the barrel? (This is important: I may have to change to a different connector!).

78CB750CAFE · « **Reply #59 on:** February 29, 2008, 12:33:05 PM »

Mark-on BOTH of the leads now the spade female receptor have broken off, leaving the plastic cover and the wire as one.
I have for now just added a ring connector to your leads until I dig out my de-soldering stuff, but I don't know how well the connector crimped down to the 22 or so gauge wire you used from the resistors.

I am at least now clear on the hook up, and REALLY glad I didn't cut off the Y from the ignitions black lead.

Drew

HondaMan · « **Reply #60 on:** February 29, 2008, 06:14:28 PM »

Quote from: 78CB750CAFE on February 29, 2008, 12:33:05 PM

Mark-on BOTH of the leads now the spade female receptor have broken off, leaving the plastic cover and the wire as one.
I have for now just added a ring connector to your leads until I dig out my de-soldering stuff, but I don't know how well the connector crimped down to the 22 or so gauge wire you used from the resistors.

I am at least now clear on the hook up, and REALLY glad I didn't cut off the Y from the ignitions black lead.

Drew

That's the odd part of this: the doubled wires and blue connector are T&B's charted mates. The blue can accept 16-20 AWG, and down to 24 AWG if doubled. Looks like I'd better make them 16-18 AWG instead (if I can get some soft MTW wire), which will make them somewhat stiff and hard to maneuver, but, oh well... $:-\$ I think I may use bare ones, then add on a different insulator cover.

LMAERO_396 · « **Reply #61 on:** March 12, 2008, 01:30:12 AM »

Installed on my CB550K

Thanks Mark!

HondaMan · « **Reply #62 on:** March 12, 2008, 07:31:17 AM »

Nice work, sarge! Looks like a squeeze play in the 550's frame, there!

mystic_1 · « **Reply #63 on:** March 12, 2008, 09:39:22 AM »

Nice clean installation. Aluminum bracket should serve well as a heat sink.

mystic_1

SohcCBs · « **Reply #64 on:** March 12, 2008, 10:21:20 AM »

Dyna sends a 1.25 ohm ballast with the S when stipulating for use with 3 ohm coils. I did so on my GL1000. I use no ballast on my CB750 for the DynaS and 3 ohm Accells. Don't know if it's the most efficient way, but I've experienced no problems that way in the 6 years since I set it up.

scondon · « **Reply #65 on:** March 12, 2008, 01:58:56 PM »

Hondaman, will these work with the Dyna 2.20hm coils as well? Sorry if this has been answered already.

I've got two bikes with 3.0 coils(screw connectors, not spade) and a third that will use 2.2 coils. Would like to try out at least one of your kits. Will PM ya for details

HondaMan · « **Reply #66 on:** March 12, 2008, 07:04:20 PM »

Quote from: scondon on March 12, 2008, 01:58:56 PM

Hondaman, will these work with the Dyna 2.20hm coils as well? Sorry if this has been answered already.

I've got two bikes with 3.0 coils(screw connectors, not spade) and a third that will use 2.2 coils. Would like to try out at least one of your kits. Will PM ya for details

I'm sure they would work OK, but wouldn't you want more resistance? I have 1 ohm and 3 ohm resistors right now. I suspect the resistance would have to be closer to 2 ohms (1.8 or so) to balance things. Many 1960s cars used 1.2 to 1.8 ohms as their resistance wires, and the Dyna performance coils I have measured are simply car-coil winding ratios in smaller packages.

CB500_k2 · « **Reply #67 on:** March 15, 2008, 05:14:02 PM »

I found that the new coils which I put in last year were 2.7 ohms by my meter. I had put in a coil relay and separate fuse for the coils to keep the main fuse from blowing with the high beam on ( H4 55/60). After reading this thread I thought that I might save my charging system by installing 2 ohm resistors in series with each coil. I found some 10W 1 ohm resistors at Radio Shack so I put two in series with the coils. With fear and concern I attempted to start my machine (CB 500 K2). To my delight, the bike started up just as quickly as prior to the revision and it ran just fine. I have to confess that I am using iridium plugs with fire effectively with a lower primary voltage. All in all, the revision works fine and I am saving 30 watts on my charging system. This is based on a single coil but neither one is always drawing current.

Klark Kent · « **Reply #68 on:** April 28, 2008, 09:34:06 AM »

As you might remember from the HMEIT (hondaman electronic ignition thingy) discussion, i was all set to try one on when i chickened out due to having 3 ohm coils. Now i don;t know why the PO fitted dyna 3 ohm coils to the stock points system- and it's running fine- but would this new thingy allow me to install the HMEIT? would this on it's own be beneficial to my bike. its a 75 550k1 with those dyna coils. otherwise stock.

thanks and good luck

HondaMan · « **Reply #69 on:** April 28, 2008, 06:55:28 PM »

Quote from: Klark Kent on April 28, 2008, 09:34:06 AM

As you might remember from the HMEIT (hondaman electronic ignition thingy) discussion, i was all set to try one on when i chickened out due to having 3 ohm coils. Now i don;t know why the PO fitted dyna 3 ohm coils to the stock points system- and it's running fine- but would this new thingy allow me to install the HMEIT? would this on it's own be beneficial to my bike. its a 75 550k1 with those dyna coils. otherwise stock.

thanks and good luck

Truth be told, KK: the bike runs better with the HEIT and Resistor Pack, if you have the 3-ohm coils on a 500/550. The overall voltage gets higher, making the whole system happier and the spark even stronger. I'm told, by our Denmark friends, that his 500 suddenly went over 11k RPM the day he installed one and went play-racing with his buddies on the twisties across the Pond. He used to struggle to reach over redline before that, he said.

Klark Kent · « **Reply #70 on:** April 28, 2008, 07:01:28 PM »

with performance possibilities like that, and my inability to leave well enough alone, id be a fool not to order a set. what is availability like right now?

hymodyne · « **Reply #71 on:** April 28, 2008, 09:51:22 PM »

I've got Accel 3 ohm coils and accel wires, and a dyna ignition. 55 was halogen headlight and a mix of two led and 4 incandescent turn lamps . If your device will help my bike's battery hold a charge, I'll buy one as well.

hym

HondaMan · « **Reply #72 on:** April 30, 2008, 06:43:46 PM »

Quote from: hymodyne on April 28, 2008, 09:51:22 PM

I've got Accel 3 ohm coils and accel wires, and a dyna ignition. 55 was halogen headlight and a mix of two led and 4 incandescent turn lamps . If your device will help my bike's battery hold a charge, I'll buy one as well.

hym

It will reduce the coil current by over 1 amp, which always helps!

hymodyne · « **Reply #73 on:** May 16, 2008, 08:12:18 AM »

+1 on the on the nice work with the resistor pack. I've got it installed with accel coils, so I'm re reading this thread to get the installation right.

hym

hymodyne · « **Reply #74 on:** May 16, 2008, 10:09:22 AM »

wiring help needed:

The Accel coils I'm running have a yellow or blue connector on one side, and each coil has a tan wire that connects to the bl/white wire from the wiring harness. the left and right on Hondaman's device wires attach where the two tan wires were attached on the coils. male bullet connector gets plugged in to the bl/white harnessleaving two unattached male bullet wires, which I can remove.

Does this sound correct?

hym

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Author Topic: Resistors for 3-ohm coils! (Read 40604 times)