Motorcycle Repair: 1975 honda CB125 charging, honda cb125, rising gas prices

Question
QUESTION: I have a 1975 honda CB125 that I am getting out and looking to ride with the rising gas prices.  Everything is working great hold for one problem.  When I turn on the turn signals they seem to work ok, but when I activate the brake or headlight(anything that draws juice)the turn signals slow down the rate of flash and get weak.  I have a fresh battery that has just been purchased and charged.  I was hoping that you might be able to point me in a direction on what I can check, how I can check it and where I might be able to find any parts that I may need.  The Honda dealership here in Spokane, WA does not seem too interested in my old relic.  Any help would be greatly appreciated.

Thanks,

Dale

ANSWER: Those relics, as you put it, are still pretty neat old machines.  It may just be a tired flasher unit.  I'd start there before I tore into anything else but I'll be happy to help you figure it out.  The first thing to do is to start the bike, turn the head light on low beam and check the battery voltage with a fully charged battery and with the engine speed above 4000 rpm. It should be 13.5-14.5 volts.  If it's not, we have a charging problem to track down.

Regards
Rich

---------- FOLLOW-UP ----------

QUESTION: Well it was the shop that refered to it as a relic, I on the other hand have fond memories of it as it was the bike I learned to ride on.  I hope to get many more years with it and to teach me son and daughter to ride on it as well.
I tried what you suggested, I had the battery fully charged and ran the bike at 4000 rpm.  I got a reading of 8.9 volts, which for a 6 volt system seemed good.  Do you have an idea of what to check next?

Thanks for your time and help,

Dale

Answer
Oh yea, those were 6 volt systems.  I'd still recommend you replace the flasher unit.  The charging system is doing all it can.  Those systems only put out enough to charge the battery.  If you step on the brake light, or if the switch is adjusted so the brake light is on all the time the battery will run down.  So there's not much extra capacity in that charging system.

Regards
Rich