Band Aid Coil Repowering Mod question

Motor Head wrote:

I'll probably step into it now, but what is your reason behind wanting to re-power your coils? What are your voltage readings that you have taken, and where is the loss of voltage at?

As many electrical problems as I have had and still have with my bike, i don't want to bog this discussion down by making it about my bike. I'm really wanting to try and understand this from a philosophical standpoint.

With my bike, it was getting less than 12v at the coils, so we got the diagram off of WG's site and did it. The bike ran much better. We took it off, it ran worse. We put it back on, it ran better.

We found the kill switch has between 19 (.19?) and 30 (.3?) ohms resistance, so that is probably bad, and will be addressed in my new, successful (so far) step-by-step strategy on resolving my electrical problems.

Even if the switch is not the problem, though, I still think it makes sense to independently power the biggest power hogs, the coils and the headlight.

bill_wilcox100 wrote:

Sorry, didn't follow that last paragraph...

What I was trying to say is, by making the coil and headlight independent of the main wiring harness, any problems in that harness lose their ability to affect the coils or the headlight. I can get it home, instead of being left beside the road cursing and jumping up and down on the kickstarter.

seanof30306 wrote:

Motor Head wrote:

I'll probably step into it now, but what is your reason behind wanting to re-power your coils? What are your voltage readings that you have taken, and where is the loss of voltage at?

As many electrical problems as I have had and still have with my bike, i don't want to bog this discussion down by making it about my bike. I'm really wanting to try and understand this from a philosophical standpoint.

With my bike, it was getting less than 12v at the coils, so we got the diagram off of WG's site and did it. The bike ran much better. We took it off, it ran worse. We put it back on, it ran better.

We found the kill switch has between 19 (.19?) and 30 (.3?) ohms resistance, so that is probably bad, and will be addressed in my new, successful (so far) step-by-step strategy on resolving my electrical problems.

Even if the switch is not the problem, though, I still think it makes sense to independently power the biggest power hogs, the coils and the headlight.

Now this logic I can follow!

Best of success,
Bill

seanof30306 wrote:

bill_wilcox100 wrote:

Sorry, didn't follow that last paragraph...

What I was trying to say is, by making the coil and headlight independent of the main wiring harness, any problems in that harness lose their ability to affect the coils or the headlight. I can get it home, instead of being left beside the road cursing and jumping up and down on the kickstarter.

Well... you're preaching to the converted on this one. :laugh:

Best of success,
Bill

Motor Head wrote:

I've never read the thread, so I can't say what was recommended. But there is a lot of relays available, sorry to say that do to the Import of low quality foreign goods it is more than likely you will pay good money for crap. If you look at some of the OEM relays, yes they cost more, they generally will be better for standing up to time, than a universal $5 relay. Some of the biggest differences you can easily see with a naked eye, and that is the material used in the construction, terminals, contacts, casing etc. It doesn't have to come from a dealer, you can still by at a replacement parts store, but look to spend $20 or more. Head lamp relays, main relays, blower fan relays, fuel pump relays, etc all have been designed for a constant load of at least 8 amps, and as much as 40.

Here is the link to the rewiring mod on WG's site:

www.wgcarbs.com//index.php?option=com_co...view&id=12&Itemid=26

It simply calls for "a standard 4 or 5 pin automotive relay"

The "load of at least 8 amps and as much as 40" is lost on me, but i would have no problem with replacing the relay on the bike with a more expensive one if it offered better reliability. I just need to know which one to get.

And Bill, I've looked at the coil repowering mod diagram on your site, but have trouble following it. Is your way of doing the mod different than what EG outlines in the link above?

Relays are sold with a AMP rating, if a universal one is bought, a OEM replacement won't tell you its rating you need to approximate the original application, say 2 head lamps, then see what yours is 1 head lamp, it should sustain the draw of 1 vrs 2.
Look at the relay you bought, does it have a part # and a AMP rating? Then look at the 4 or 5 pins, all silver or is 2 of them copper in color?
The other problem can be how a contact point relay is mounted, which loudhvx was pointing out, vibration can have a Ill effect on the contact points causing intermittent contact. He recommended to mount the relay with a Isolator at the bracket so as to not be vibrating on a solid mount.

seanof30306 wrote:

Motor Head wrote:

I've never read the thread, so I can't say what was recommended. But there is a lot of relays available, sorry to say that do to the Import of low quality foreign goods it is more than likely you will pay good money for crap. If you look at some of the OEM relays, yes they cost more, they generally will be better for standing up to time, than a universal $5 relay. Some of the biggest differences you can easily see with a naked eye, and that is the material used in the construction, terminals, contacts, casing etc. It doesn't have to come from a dealer, you can still buy at a replacement parts store, but look to spend $20 or more. Head lamp relays, main relays, blower fan relays, fuel pump relays, etc all have been designed for a constant load of at least 8 amps, and as much as 40.

Here is the link to the rewiring mod on WG's site:

www.wgcarbs.com//index.php?option=com_co...view&id=12&Itemid=26

It simply calls for "a standard 4 or 5 pin automotive relay"

The "load of at least 8 amps and as much as 40" is lost on me, but i would have no problem with replacing the relay on the bike with a more expensive one if it offered better reliability. I just need to know which one to get.

And Bill, I've looked at the coil repowering mod diagram on your site, but have trouble following it. Is your way of doing the mod different than what WG outlines in the link above?

No, there is no difference... identical mod. True, WG's is much easier to follow, including the use of a separate 10 Amp fuse. Good stuff!

Best of success,
Bill

Motor Head wrote:

Relays are sold with a AMP rating, if a universal one is bought, a OEM replacement won't tell you its rating you need to approximate the original application, say 2 head lamps, then see what yours is 1 head lamp, it should sustain the draw of 1 vrs 2.
Look at the relay you bought, does it have a part # and a AMP rating? Then look at the 4 or 5 pins, all silver or is 2 of them copper in color?
The other problem can be how a contact point relay is mounted, which loudhvx was pointing out, vibration can have a Ill effect on the contact points causing intermittent contact. He recommended to mount the relay with a Isolator at the bracket so as to not be vibrating on a solid mount.

OK, so for the coils, you were saying a relay designed for a constant load of 40 amps is best?

Is it really a question of wiring, or more a question of money, or laziness, or fear?

I vote money. :laugh:

Do whatever the hell you want to really, just remember that every blasted thing on your 30+ year old bike is going to fail. period. Its just a matter of time.

All things aside, good maintenence of the wiring, fuel system, engine, whatever - is always the best preventative measure. You will frequently prevent/discover a possible failure with constant attention to ALL the critical systems of a bike.

You can run a couple new wires, and replace a few cheap switches, and tada: full voltage to your coils. Just look at your wiring diagram and follow the positive power from your battery.

Its also not really a big issue to go thru the bike an clean up/solder all the connectors. Takes like a few hours, then thats it.

Whatever. :laugh: :woohoo: :laugh: :blink: :silly:

Well that is not exactly what I said, I wasn't clear enough. What you need is a relay that will handle your load, coils if that's what you want. Without knowing what current your system uses in AMPs, dyna something right, I can't tell you a relay rating, But I can say that since the 3 phase stator output is only about 20 AMPs there is now way you will exceed that without loosing battery storage, Dead again. So I would simply put a 20 AMP relay in for your use, that should be plenty, and get a good quality one and mount it out of the weather and free from vibration. I would also fuse the circuit to the coils for sure, is 10AMPs enough? Probably but with a current measurement in AMPs of the draw, its a guess.

Two things to add:

Generally, headlights draw a lot of amperage. Car makers shy away from using swithces that carry high amperage in a car's dashboard, so they use relays elswhere in the car that are activated by the dashboard switches. I copied this approach in my truck when adding a pair of 55 watt lights to the rear for backing up in offroad conditions. I am happy with this arrangement.

I haven't heard of anyone intalling the coil mod for the same reason given above. Generally, (but not always) folks using the coil mod do so in order to increase the voltage going to the coils over the voltage they measure going through the stock wiring harness arrangement. This is where the "band-aid" term comes from. When they were new, these bikes delivered sufficient voltage to the coils through the stock wiring harnesses. Over time, the wiring on many bikes developed issues that reduced the voltage getting to the coils through the stock wiring. Such things as corroded bullet connectors, deteriorated handlebar switches, abraded wiring, etc. can impact the voltage getting to the coils. When this happens the owner can find and correct the wiring issue to restore the quality of the stock wiring to original specs or ignore the problem and add the coil mod. Either approach will give sufficient power to the coils. The coil mod may be easier in many cases, but leaves the underlying problem in place. This may or may not lead to a different problem later (for example a wire bundle being worn through because of improper routing may affect other electrical components as the wear continues to short or break other wires.)

The decision to fix the existing wiring or add the coil mod is an individual choice that depends on the electrical skills, available time, and preference of the owner. Personally, I wouldn't rest knowing I had bad wiring on my bike that I had bypassed, but that's just me, so mine is stock. Others don't mind stuff being a bit off as long as the bike runs ok, and still others might have perfectly sound wiring systems but feel the mod gives them a little more power to the coils than the stock setup. Ed

Motor Head wrote:

Well that is not exactly what I said, I wasn't clear enough. What you need is a relay that will handle your load, coils if that's what you want. Without knowing what current your system uses in Amps, Dyna something right, I can't tell you a relay rating, But I can say that since the 3 phase stator output is only about 20 Amps there is now way you will exceed that without losing battery storage, Dead again. So I would simply put a 20 AMP relay in for your use, that should be plenty, and get a good quality one and mount it out of the weather and free from vibration. I would also fuse the circuit to the coils for sure, is 10 Amps enough? Probably but with a current measurement in Amps of the draw, it’s a guess.

IMHO, I would say MH is right on two counts. First, that 20 Amp would do and second that it is possibly vibration that killed the 3-year old relay and not heat due to current... but just a guess.

Remember, the specifications SHALL be printed on the component. The cheap relay I bought had the following printed on it:

NVF4-2C-Z40a
NO: 40A/14VDC
NC: 40A/14VDC
COIL DC12V
NHG

The "NHG" is just the manufacturer and "NVF4-2C-Z40a" is just the part number, so forget about those numbers.

Again, IMHO, the 40A is the important part. Also, as a rule-of-thumb it’s a good practice to run at only 50% of the rated value or less for long term reliability. The current draw should be less that 10 Amps so a 20 Amp or 40 Amp rated relay should, of course, do the job just fine and for a long time.

Best of success,
Bill