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Q This is in regard to Loren Stephenson’s July-issue electrical question ("Watt’s the answer”) concerning brighter lighting for his Honda. Actually, his Honda dealer was correct in that it is better to install a lightbar than a brighter headlight bulb, but not for the reason the dealer stated.

The problem is one that Honda does not want to admit. Ever since the early 1970s, when the “lights-on” laws were enacted, motorcycles have come from the factory without switches that allow us to turn the headlights off while starting the bike or doing maintenance. To reduce the load on the battery while the starter button is pressed, some manufacturers incorporated a timedelay relay that would not light the headlight until 30 seconds after the keyswitch was turned on. Honda’s technique was to put a second set of contacts on the starter pushbutton switch to reduce the load on the battery while the rider tries to start the bike.

But that switch is not ruggedly constructed. Repeated making and breaking a 5-amp connection causes corrosion and pitting of the switch’s headlight contacts. The heat caused by the corrosion of the contacts melts and deforms the plastic inside the switch, so after a period of time, the switch fails-sometimes just the headlight contacts, but often the starter contacts as well.

Changing to a higher-wattage headlight bulb causes those contacts to fail sooner.

The lightbar the Honda dealer would likely sell Mr. Stephenson is a Hondaline product wired to get its power from the taillight circuit, not the headlight, so it would not add to the current through the starter switch’s headlight contacts. The kit also includes a handlebar switch so the rider can turn off the lightbar lamps when they aren’t needed.

To safely run a more powerful headlight in a Honda VTX1800, VTX1300, VT1100 or 1500 Valkyrie, I recommend adding a relay to the headlight circuit. Power for the headlight would come directly from the battery; the voltage for the coil of the relay could come from the headlight contacts in the starter pushbutton switch. This would reduce the current through the headlight contacts of that switch from five amps to one-half amp or less. Just thought you should be aware of this ongoing problem and why your answer might cause Loren Stephenson a problem in the future. Dale Halpin

Schenectady, New York

A Thank you very much for the terrific input. You are right-l had no knowledge of this problem.

I’ve fitted higher-wattage headlight bulbs to numerous other makes and models without the sort of problems you describe, which is why I offered Mr. Stephenson the advice that appeared in Service. This is one of the risks in writing a question-and-answer column about motorcycles. With so many models on the market (about 450 in 2006), complicated by the frequent changes made to most of them every few years, it’s easy for problems and weaknesses such as this to evade my knowledge. I will correct my oversight, and I thank you once again.