January 2009 Technical Corner

Since 1975 when the Honda Gold Wing was introduced, I've discovered a few little secrets about how to preserve the life of your Gold Wing alternator.

All four-cylinder Gold Wings were equipped with a so-called maintenance-free alternator. These simple alternators consisted of a 12-pole permanent magnet rotor and an 18-pole stator. Contrary to popular belief, stator failure does not occur due to a faulty stator. The problems usually begin at the 3-pin connector between the stator and the voltage regulator. Since these alternators put out full power all the time the engine is running, the regulator shunts excess current to ground intermittently. The shunting process occurs when the regulator senses a full charge on the battery. Consequently, some voltage will drop on the 3-pin connector, and the connector will heat up. Dissimilar metals used in the connector cause the volt-age drop. Any time we have a voltage drop in an electrical circuit, heat will build up at the point of volt-age drop. The heat will melt the connector and some of the insulation on the three yellow wires, and pretty soon we have a direct short circuit between two of the three yellow wires. Our stators are designed to handle a yellow-to-ground short circuit, but they are not designed to handle a yellow-to-yellow short circuit. Any time we short any two phases of a three-phase power supply; the result will always be a power supply failure. These failures are more likely to happen with the 1984-1987 GL1200 Gold Wings, but I've seen similar failures on the 1975-1983 GL1000 and GL1100 models also.

What can we do to prevent stator failures on our Classic Wings? My recommendation is to cut the yellow wires at the 3-pin connectors and connect them using solder and heat-shrink insulation. If the job is done correctly, the wires won't heat up or turn brown from heat.

The rest of this article applies to ALL Gold Wings. The alternators on the GL1000 models are rated at 18 amps at 5000 RPM. The alternators on the GL1100 models are rated at 21 amps at 5000 RPM. The alternators on the GL1200 models are rated at 25 amps at 5000 RPM. The alternators on the GL1500 models are rated at 39 amps at 5000 RPM. The alternators on the 2001-2005 GL1800 models are rated at 78 amps at 1000 RPM. The alternators on the 2006-2009 GL1800 models are rated at 92 amps at 1000 RPM.

If you load down your electrical system with a lot of unnecessary electrical accessories, make sure that your accessories do NOT draw more amps than your electrical system can supply. Electrical over-loads can cause alternator failures and premature brush wear WITHOUT BLOWING ANY FUSES OR DAMAGING RELAYS AND CIRCUIT BREAKERS!

The most common type of alternator failure I've seen on the GL1000, 1100, and 1200 models is stator failure. The most common type of alternator failure I've seen on the GL1500 models is brushes sticking inside the brush holders and rotor winding failure.

As of this writing, I have NEVER heard of any kind of failure on the GL1800 alternators. While conducting seminars at recent Wing Dings, the only com-plaints I’ve heard about the GL1800 alternators were that they were noisier than the GL1500 alternators. I advised the owners to get the noise checked out by an authorized Honda dealer.

I recommend checking the brushes in the GL1500 Gold Wings every 50,000 miles. If you're not mechanically or electrically skilled, get your authorized Honda technician to do the job for you. If brushes are sticking in the brush holders and the problem isn't corrected, rotor failure can occur. If the brushes are worn beyond the wear mark, they should be replaced. This is usually every 40,000 miles or so.

GL1500 alternator rotors cost about $225, while complete alternator assemblies cost about $250. If your rotor fails due to an open or short circuit, you will probably be better off replacing the whole alternator with a new one. My recommendation is the following:

If you intend to keep your GL1500 rather than replacing it with a GL1800, spend a little more and get the Compu-Fire alternator and sealed battery. You can order them through their ad in Wing World Magazine. The Compu-Fire alternator has proven to be maintenance free and will deliver 90 amps at 5000 RPM.

Last but not least, if your battery is showing signs of giving up, let it die with dignity and replace it with a new one. A dying battery can have a low electrical resistance, resulting in a high current draw. If the current draw is high enough to put an extra heavy load on the alternator, you might be flirting with alternator failure. Batteries are a lot less expensive than alternators.

Howard Halasz, Chapter M2 Technical Coordinator

Texas Chapter M-2

Chapter M-2's Technical Corner