Too much of a good thing?

[stopwatch]

I've been thru 2 voltage fixes over the last 3 years. Life span is about 18 months before the fuse holder melts. The second time I used 10 gauge wire and a maxi fuse holder. This time I've used 8 gauge 600 volt capacity wire and one of those "heat resistant" clear bullet shaped maxi fuse holders that seem to have more surface area for the fuse to contact. Now I'm getting 14.5 volts at idle!

The motorcycle techs I've talked to don't recommend this modification. They say a near constant flow of 13- 14 volts thru the fuse holder connections creates too much heat over a long period of time and causes the failure. A couple of them said it could damage the regulator/ rectifier by pulling too much juice thru. One tech said if the battery is in a near constant state of overcharging, it could short out inside and THAT would fry the ECM ($1799)!

All my connections have been crimped and soldered. I've also used liberal amounts of dielectric grease.  

What do you all think? Is 14.5 volts at idle too much? Maybe I'm just being paranoid, but I've considered removing the mod and going back to stock. Although stock voltage is 12.5 at idle and dips down to 12.2 at 3000 rpm.

[iansoady]

I'd talk to different techs. Normal voltage of a touch over 14 should be fine.

However you do need (whether having done the mod or not) to ensure good connections and decent sized cabling.

[JetdocX]

Wire is not rated for voltage.  It's rated by the amount of current it can handle without turning the insulation into smoke.

What are you trying to run?

[stopwatch]

I'm thinking two 10 gauge wires going to one 8 gauge should be sufficient. Also, the connections aren't where the high heat is present. It's always at the outgoing spade terminal of the fuse holder. Seems if there was a bad connection the resistance and subsequent failure would be in that area.

I've been on some long trips with both of the previous mods. The first mod lasted about 14 months/ approx 12,000 miles and included a trip from Knoxville to Chicago. The second mod lasted a little longer (approx 15,000 miles) and included trips from Knoxville to New York and Sturgis.

I guess the voltage with the latest mod I've done doesn't seem to be that high once the bike warms up. It does settle down to 14.1- 14.3 volts.

Have any of you guys who've done the mod also put down some serious miles in hot weather? Maybe the 12 minute tunes I've done have produced abnormally high ambient heat coming up from the engine and reg/ rectifier and with the bike just sitting there idling for extended periods the heat has no place to go like it does when the bike is moving. I had just finished my 60,000 mile service and did a 12 min. tune in pretty hot weather. About 300 miles later is when the failure occured. On the previous mods I had the fuse holder above the reg/ rectifier. This time I've located the fuse holder over the battery on top of a thin piece of rubber to keep it from making direct with the battery.

[stopwatch]

The wire I've used this time is (according to the folks I bought it from: Hi- Fi Sound Connection) 8 gauge 600volt "super twist" power wire commonly used in high performance audio amplifiers.

The connections shouldn't be the problem since the failures never occur there.  
 
Although I've got connections for a heated vest and auxillary lights, I don't use either very much and very rarely use both at the same time.

There have been several inmates who have had the voltage fix fail after some time. I really find it hard to believe it's being caused by inadequate connections. Those folks who have the failures always have the failure in the fuse holder. Seems as though it may be necessary to locate the fuse holder in as cool an area as possible, take the seat off to allow heat to escape during any hot weather 12 minute tune- ups, and just plan on replacing the fuse holder every 12,000 miles (or every year) to be safe.

I'm very curious if there's any common factor (like running 12 minute tune- ups in hot weather with the seat on the bike)  between those of us who've had failures even after going to maxi fuses and 10 or 8 gauge wires. When I do the 12 min. tune, I wait till the fan cuts on and then wait another 12 minutes. That's a long time to sit in place in hot weather with very little air circulation.

[oxnsox]

You should be buying wires and fuse hardware from either an Auto store or a Marine store.

All Cables are rated for Current. Thats Amps. Voltage ratings are (generally) for the insulation materials around the wire.  

Audio signals (which are effectively AC) behave differently to DC. Audio is more voltage driven, and tends to run on the skin of the cables, so the trend is to have many (often) fine wires in the core of audio cables. (This also makes them more flexible)
DC runs thru the whole conductor, so when current increases you want heavier gauge conductors making up the weight of the cable.

Heat in connectors, cables and fuseholders, is caused by not having enough area in the cable or connection for the current flowing through it. It means you either have cables that are too thin, or connections (like spade terminals) that don't have enough surface contact area (or maybe dirty?). Heat means losses-means voltage drops.

Failures in a fuse holder means you're using the wrong type of fuse holder. Personally I use inline blade fuse holders, but you may need to go to a maxi-fuse holder for higher current ratings.

The most important component to get airflow for cooling is the rec/reg as its located/mounted in a poor place for airflow, and what we're wearing and how we sit on our bikes doesn't improve that airflow.

Any decent battery should be able to handle the charging voltage of the regulator, the system is designed to reduce the volts as the battery charges.  If it doesn't it will damage your battery, which could lead to failures back thru the charging system.  

If the voltage doesn't reduce it'll be because you're maybe using most of the power in your other systems and the battery is failing to charge properly, maybe a poor quality or failing battery, or you've wiring issues that affect the charge/use balance.

You have to look at your power system in its entirety. Stator, regulator, battery, wiring, load. Failure of one item (say regulator) is likely to damage (or stress) the stator and battery as well. Sometimes these won't fail immediately after but they're more likely to cause on going issues that aren't always explainable down the track.

[stopwatch]

Hi oxnsox. Just curious. Have you done this voltage mod and how long/ how many miles have you had the fix in place?

One reason I was getting so much voltage from my latest voltage fix was because I didn't realize I had switched my headlights off when I took the voltage measurements. That was enough to put the voltage up near the high end, but when I turned the headlights back on the voltage dropped back to a more normal 14.2.

As I mentioned above, the last failure was in a 30 amp rated maxi fuse holder with 10 gauge wire in exactly the same place as the previous failure in a "standard" size (atc) 30 amp fuse holder with 12 gauge wire.
The wire in both instances was automotive wire.

THIS time I've used 8 gauge wire designed for 12 volt, high performance car audio amplifier applications and a maxi fuse in a high performance, heat resistant maxi fuse holder which appears to have more surface area the the typical maxi fuse holder.

All other aspects of the charging system have checked out fine.

My original inquiry was meant to find out if my latest voltage fix could be sending so much power to the reg/ rectifier as to make it too hard to "bake off" the excess voltage and to find out if any of the inmates that have experienced the same failure in the same location (fuse holder) had put their Tigers thru similar high heat circumstances (ie. 12 minute tunes, 800 mile days in high temps).

There's too much evidence to be just coincidental with ALL the failures occuring in the same place. I'm confident this voltage mod not only requires proper wire gauge and large fuse surface area, but also requires regular maintenance (fresh dielectric grease occasionally) and replacement of the fuse holder and fuse every year or so IF it's a bike racks up considerable miles each year.