Volt meter drops 90 flhtcu
Road Master
Joined: Aug 2007
Posts: 848
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From:
If the entire wire is hot, and not just hot at the end, then that indicates either a wire improperly sized (too small) for the circuit load, or a circuit load over the design spec. As others have not noticed a problem there, I'm going with too much juice in that circuit. Now, why? Is something shorting in that circuit? Is there a huge radio or amp on there, or extra lights? One or the other.
All the red wires that connect to the circuit breaker are hot. There is only 2 inches tops of them that are exposed. That 2 inches is hot.
The entire wiring system on my bike is stock. The red wires are all stock gauge.
I don't have any large radios or amps or lighting. Its a stock 1990 FLTHCU
Whether or not I have the spot lights or the high beam on, the red wires are hot when the bike is running.
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,195
Likes: 3,085
From: NW AR
Well, it would also be possible that whatever is on that circuit is failing and taking too much current. Or there is a short somewhere down the line.
Is that the main wire feeding the whole bike? If that us feeding the whole bike, which it kinda sounds like, they may be too small. Our electrical systems are a weak point. Don't get me started on the orange wire for the accessory circuit. So it is possible that the wire is just too small for the load. You don't have some kind of high power head light or super-performance ignition/coil, do you?
If you put an ammeter in series with the one wire leading from the main breaker under the seat, that should tell you the whole load, but it should handle full alternator output for your bike at least.
Is that the main wire feeding the whole bike? If that us feeding the whole bike, which it kinda sounds like, they may be too small. Our electrical systems are a weak point. Don't get me started on the orange wire for the accessory circuit. So it is possible that the wire is just too small for the load. You don't have some kind of high power head light or super-performance ignition/coil, do you?
If you put an ammeter in series with the one wire leading from the main breaker under the seat, that should tell you the whole load, but it should handle full alternator output for your bike at least.
HDF Community Team
Joined: Dec 2005
Posts: 5,378
Likes: 2,574
From: NC USA
With the exception on the stator/regulator which terminates at the main breaker, every bit of "juice that runs thru the bike is connected where the two wires you mentioned are tied to that breaker. Cleaning that connection and/or replacing the ring terminals would be the first thing to do. And remember, it's "all" happening right there so it's normal for them to get warm and a bad connection anywhere could cause overheating and if the wires at the other breakers are normal temp, it'd have to be the main switch or a connection at it. But that's definitely the place to start and work out from there (toward main switch etc)
Road Master
Joined: Aug 2007
Posts: 848
Likes: 8
From:
Connector 10B is the plug end for the factory radio power and the red wire is the constant "hot" for the radio memory.
With the exception on the stator/regulator which terminates at the main breaker, every bit of "juice that runs thru the bike is connected where the two wires you mentioned are tied to that breaker. Cleaning that connection and/or replacing the ring terminals would be the first thing to do. And remember, it's "all" happening right there so it's normal for them to get warm and a bad connection anywhere could cause overheating and if the wires at the other breakers are normal temp, it'd have to be the main switch or a connection at it. But that's definitely the place to start and work out from there (toward main switch etc)
With the exception on the stator/regulator which terminates at the main breaker, every bit of "juice that runs thru the bike is connected where the two wires you mentioned are tied to that breaker. Cleaning that connection and/or replacing the ring terminals would be the first thing to do. And remember, it's "all" happening right there so it's normal for them to get warm and a bad connection anywhere could cause overheating and if the wires at the other breakers are normal temp, it'd have to be the main switch or a connection at it. But that's definitely the place to start and work out from there (toward main switch etc)
So.. this is what I am going to do:
Tonight I am going to swap out that wimpy red wire that runs from the 30 amp breaker in the rear to the 15 amp breaker in the front with a 10awg THHN/THWN/MTW 600v stranded wire and I am going to solder on some high quality ring terminals. That should take care of the heat build up at the ring terminal ends. Besides the heat.. the bikes electrical system seems to be fine now. I replaced or cleaned just about every hot and ground point.
Road Master
Joined: Aug 2007
Posts: 848
Likes: 8
From:
Connector 10B is the plug end for the factory radio power and the red wire is the constant "hot" for the radio memory.
With the exception on the stator/regulator which terminates at the main breaker, every bit of "juice that runs thru the bike is connected where the two wires you mentioned are tied to that breaker. Cleaning that connection and/or replacing the ring terminals would be the first thing to do. And remember, it's "all" happening right there so it's normal for them to get warm and a bad connection anywhere could cause overheating and if the wires at the other breakers are normal temp, it'd have to be the main switch or a connection at it. But that's definitely the place to start and work out from there (toward main switch etc)
With the exception on the stator/regulator which terminates at the main breaker, every bit of "juice that runs thru the bike is connected where the two wires you mentioned are tied to that breaker. Cleaning that connection and/or replacing the ring terminals would be the first thing to do. And remember, it's "all" happening right there so it's normal for them to get warm and a bad connection anywhere could cause overheating and if the wires at the other breakers are normal temp, it'd have to be the main switch or a connection at it. But that's definitely the place to start and work out from there (toward main switch etc)
Tonight I am going to swap out that wimpy red wire that runs from the 30 amp breaker in the rear to the 15 amp breaker in the front with a 10awg THHN/THWN/MTW 600v stranded wire and I am going to solder on some high quality ring terminals. That should take care of the heat build up at the ring terminal ends. Besides the heat.. the bikes electrical system seems to be fine now. I replaced or cleaned just about every hot and ground point.
HDF Community Team
Joined: Dec 2005
Posts: 5,378
Likes: 2,574
From: NC USA
I checked it out again last night and its only the single red hot wire that runs from the main 30 amp breaker to the 15 amp breaker that is getting hot. Its only the ends of the cable where the ring terminals are that gets moderatly warm to mildly hot after about 20 minutes of running with every light on.
Tonight I am going to swap out that wimpy red wire that runs from the 30 amp breaker in the rear to the 15 amp breaker in the front with a 10awg THHN/THWN/MTW 600v stranded wire and I am going to solder on some high quality ring terminals. That should take care of the heat build up at the ring terminal ends. Besides the heat.. the bikes electrical system seems to be fine now. I replaced or cleaned just about every hot and ground point.
Tonight I am going to swap out that wimpy red wire that runs from the 30 amp breaker in the rear to the 15 amp breaker in the front with a 10awg THHN/THWN/MTW 600v stranded wire and I am going to solder on some high quality ring terminals. That should take care of the heat build up at the ring terminal ends. Besides the heat.. the bikes electrical system seems to be fine now. I replaced or cleaned just about every hot and ground point.
DO NOT solder the terminals. I know this sounds contrary to what a lot of people will tell you, but the fact is a soldered connection will carry high voltage just fine but will not allow the wire/connection to carry the amperage as well as a crimped connection.
I'm not an engineer but ... Anyone who works with, or knows electricity will tell you finer stranded wire carries more amperage. The electrons travel thru each strand of a wire. The more strands, the more efficiently the electons can travel with less resistance. When you solder stranded wire you negate the up-side of the fine strands and effectively turn it into a solid piece of wire which cannot let the amperage flow as easily. It turns the terminal into a choke, in a manner of speaking.
Anyone who cares to dispute or correct me is certainly welcome because I can't reference where I read that, but think about it - you will never see a battery cable or welding cables engineered with soldered ends. So DO use heat shrink at the terminals to protect the strands from corrosion (may be all that's wrong with your existing wire) but don't waste time with solder unless working with single strand wire.
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,195
Likes: 3,085
From: NW AR
You're mistaken, there Rufus. Finer stranded wire does not carry more amperage than coarser stranded wires, provided the cross section is the same. The resistance of the wire is not going to go down by soldering. Resistance is cross sectional related, and adding lead/tin solder to the copper will only increase the cross section and decrease the resistance, overall, as you describe. A finer stranded wire may be more densly packed into the whole bundle than a coarse stranded wire, and thus have more cross section than the coarse, and that may be what you have heard.
The reason some do not solder and crimp instead is because it is easier (faster and cheaper) _with very expensive professional tools and ends_ to get a high quality crimp connection than to get a good solder connection. Now, if you don't have the ultra high dollar crimpers (sized especially for your wire and connector) and the right connector, then it is easier to get a good connection with what you have and soldering, if you know how to solder properly. Also, in some extreme circumstances, a REALLY GOOD crimp connection may in fact be stronger than a really good solder connection. The connection itself may not be stronger, but there is some solder that wicks up the insulation, and that can make the area brittle.
Given our tools and skills, the best connection in my professional opinion (7 years Radio Electronics Officer in USMM), is to take the crimp terminal properly sized for the wire, crimp it on the wire, then solder it on after crimping.
The reason some do not solder and crimp instead is because it is easier (faster and cheaper) _with very expensive professional tools and ends_ to get a high quality crimp connection than to get a good solder connection. Now, if you don't have the ultra high dollar crimpers (sized especially for your wire and connector) and the right connector, then it is easier to get a good connection with what you have and soldering, if you know how to solder properly. Also, in some extreme circumstances, a REALLY GOOD crimp connection may in fact be stronger than a really good solder connection. The connection itself may not be stronger, but there is some solder that wicks up the insulation, and that can make the area brittle.
Given our tools and skills, the best connection in my professional opinion (7 years Radio Electronics Officer in USMM), is to take the crimp terminal properly sized for the wire, crimp it on the wire, then solder it on after crimping.
HDF Community Team
Joined: Dec 2005
Posts: 5,378
Likes: 2,574
From: NC USA
OK, I stand corrected and sincerely appreciate the electonics lesson DrHess. I figured my last post would get me one, just glad it was someone who actually knew something 
They wouldn't let me into radio or medical school because of color deficient vision, but I get by ...
They wouldn't let me into radio or medical school because of color deficient vision, but I get by ...
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Seasoned HDF Member
Joined: Aug 2007
Posts: 8,195
Likes: 3,085
From: NW AR
I'm colorblind in blues and greens, by the standard dot tests. I see blue and I see green, but they just don't look the same to me as to other people. When they are really dark, I have trouble telling them apart. When I took my physical for my USCG license, they will give you the option of taking a lantern test instead of the dot test, which I could pass. I won't tell the rest of that story on teh webz. Come on over to this side of the Mighty Mississippi and I'll tell ya. Medical school could care less if you're colorblind.
