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Motorcycle Repair/1976 XL 125 honda


When the signal lights are on ,it makes the tail light and speedo light blink also if the light are on .if the light switch is off everything work just find ,have checked all wires to my best ,any ideas ?????

Doug, that is pretty normal for those bikes. They only have a 6v battery and when there is a full lighting load on the battery and charging system, the signals will pull a surge of power from the system. All you can do is to have a fully-charged, load-tested battery in place and perhaps turn up the idle speed just a bit, if you are doing a lot of slow, in-town driving. Motorcycle batteries only last a couple of years, even with good maintenance. When they sit down for the winter the batteries can sulfate and discharge, losing their original voltage rating.

US models have "always ON" headlights, which aggravate the problem, even further.

Do make sure that all of your lights are the correct wattage bulbs and that the wiring connections AND GROUNDS are clean and tight.

You will probably notice that if you are riding along at speed, after the bike is warmed up, that the signals might not affect the other lights as much, because the charging system is functioning at its fullest. There is very little charging going on at idle, so you are losing the electrical battle below about 2500 rpms. There is little that you can do about this condition, so you can stop trying to fix it!

Bill Silver

Motorcycle Repair

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Bill Silver


Need help with vintage Hondas from the 1960s? I am an expert with 250-305cc bikes in particular and most all of the other pre-91 models, in general. I do NOT claim to have a great deal of experience on Gold Wings, Cruisers, ATC/ATVs and dirt bikes.


I have owned/ridden/maintained Honda motorcycles for 35 years. I have written five books on Honda repairs and collecting. I was a service manager for two Honda shops back in the 1980s.

VJMC (Vintage Japanese Motorcycle Club) of North America

VJMC newsletter, as editor for two years and as contributing editor currently.

3 years auto shop in high school, teacher's aide in Automotive Technology in Jr. College, Diesel mechanic course in college, self-taught mechanic and automotive writer.

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