Topic: 1975 Honda CB125s - Possible Electrical Problem

[chriscraft42]

I am having a strange issue with my 1975 Honda CB125s signal lights. The right and left signal lights (front and back work until I put the headlight on and then they stop working. Does anyone have any suggestions to correct this problem?. All other electrical on the bike works just fine...thanks 

[333]

Do you have a multi meter?  What is the volts reading at the battery with;

1. engine off
2. engine only on, at idle.
3. engine only on, at about 2,000 rpm
4.  #2 and 3 with headlight on

If the battery reads below specified voltage with #1, it probably needs replacing.  If it is bad, it probably is drawing too much from the charging system to run everything.

[mlinder]

Blinker mechanisms get old. The older the get, the more resistance they have. With the headlight on, there just may not be enough current to overcome the increased resistance of the old blinker.
There are a number of 'electronic' blinkers that you can buy for 7-12 bucks at places like schucks, autozone, etc.
They do not use the resistance to blink, and will blink with whatever current they are getting.

Give one a try.

[333]

Mlinders idea is a good one except for one thing.  I don't think they make those for 6 volt systems.

[mlinder]

Mlinders idea is a good one except for one thing.  I don't think they make those for 6 volt systems.

Yer probably right.
Have to pick up a honda part, then.

[kirkn]

Well, no, not necessarily a HONDA part. 

I'll agree that the first likelihood is a new blinker relay.  However, a decent automotive store (not really Discount Auto Parts, or PepBoys, etc) should be able to get you one.  After all, there WERE 6-volt autos, although quite a while ago now.  Probably cheaper than Honda, too.  Or even ebay, or the internet, generally.






Has it REALLY been 40 years since 6-volt VW's?