How many amps?

[Jaguarjoe]

My bike died the other day. The fuse holder assembly melted all around the main 15 amp fuse. It got so hot the battery wire soldered to the back of the fuse clip unsoldered itself.
I thought it was just lousy connections on the fuse holder assembly so I bought a new, better fuse holder from Mouser Electronics. I made a little bracket to attach it to the same holes that held the old fuse holder then I soldered up all the wires going to it.
I was very confident that would solve my problem, but man was I wrong! The new fuse holder and the 15 amp fuse gets extremely hot too. Way too hot. The Honda voltage regulator gets very warm too.
I put an ampmeter in line with the fuse and found that the voltage regulator is putting out 15 amps of current, most of it apparently going into the battery.
The battery voltage is 12.5 V with the bike off and rises to 14.2 V when the bike is running at 2,000 RPM so that's about right.
My two questions are:
How many amps can the charging system deliver and how can a good battery eat those 15 amps without exploding?
Do I have a bad Honda R/R?

[BassCliff]

Cooking with electrons

Hi Mr. Jaguarjoe,

It's possible that you have a bad r/r unit. It's also possible that you've got corrosion in the charging system connections, ground connections, or somewhere else in your wiring harness (ignition switch?), that's causing more resistance. More resistance causes bigger voltage drop which, in turn, causes your r/r to try and put out more voltage.

Do you have the ground wire from the r/r connected directly to the battery's negative terminal? Check and clean every electrical and ground connection on your bike, from the headlight bucket to the tail light. I know it's tedious, but it helps the electrics on these old bikes immensely. Scrub all the chassis grounds with a wire brush and steel wool to remove corrosion. Do the same with your battery terminals, solenoid terminals, every connection you can. Have you gone through The Stator Papers recently? Keep us informed.


Thank you for your indulgence,

BassCliff

[Steve]

The output of the charging system is directly related to engine speed, up to the point that the regulator starts regulating. That is why you will see peak voltage about 2000-2500 rpm, then it drops a few tenths.

How does the battery eat those 15 amps? Easy. It doesn't.
Your headlight uses about 5 amps. The coils use about 5 amps. The tail light is not quite an amp. This means that only about 4 amps go to the battery on a regular basis. If you have running lights in the front signals, take off another amp of current that is going to the battery.

And we wonder why our battteries don't get/stay charged on a regular basis.

[SqDancerLynn1]

Disconnect the regulator & see if it still gets hot..

[geezer]

This problem is usually caused by corroded connections. It takes more power to get through a corroded connection and this makes heat that cooks the fuse.

These links should help you.

http://www.OregonMotorcycleParts.com/FAQ.html

http://www.oregonmotorcycleparts.com/ConnectionRepair.html

http://www.oregonmotorcycleparts.com/GWstatorplug.html

Tony