electrical problems

Forest · Post by **Forest** » Sat Jun 18, 2011 10:55 pm

so let me say im new to posting questions on this forum but I always read what you guys talk about.. got to love bike talk... but now I need help... electrical is not my strong point.. i have a 61' honda dream 305.

so my problem is that my taillight bulb keeps blowing out. As you know its a duel filament bulb and the brake light filament never blows out, ONLY the running light filament. Ive replaced it three times and within a day its blown.

So heres what I've noticed: when i rev the engine the headlight seems to brighten due to increase in electrical current... i thought i also had a blown low beam headlight filament but when i rev the engine it flickers slightly... so I was thinking that if the head light is flucuating in power then maybe when the engine is running high that the taillight bulb is getting an excess of current, causing the blowout.

Any suggestions would be greatly appreciated... Its getting risky riding home from work at night!

Thanks,
Forest

Jethro · Post by **Jethro** » Sun Jun 19, 2011 11:30 am

Hi Forest.
A weak or dead battery can blow your lights. When a battery is dead or almost, there is nowhere for the voltage coming from your charging system to go. The battery sort of is a shock absorber for the electrical system. I had a similar problem on my CL350 a couple weeks ago. With your headlight now, sometimes when they burn out there is only a small break in the filament. So with engine vibration the filament may be making contact slightly causing a flicker.

Hope this helps and let us know what comes of it.
Jethro

brewsky · Post by **brewsky** » Sun Jun 19, 2011 6:49 pm

Jethro is right, sometimes a filament will break and just barely make contact at a given vibration frequency.

I had one head light that would work fine at low engine speeds and test good with an ohm meter, but would go out at higher engine rpm due to vibration.

If your high beam is good, try running it on all the time and see if the tail light situation stops.

Running with the switch in lights on position with a blown headlight could probably cause excess current and the tail light to blow.

Forest · Post by **Forest** » Mon Jun 20, 2011 10:13 am

That all makes sense... the headlight low beam definitely flickers when engine vibration is at its highest point; it even stayed on for a minute when I lightly tapped on the lens cover- must be the filament like you said.

And as for the taillight, I'm sure your right about that too. I just checked the battery and it seems to be pretty low. I'm heading out to the garage now to charge the battery and put in a little more distilled water.
Hopefully this fixes my daily taillight blowout.

Thanks for the help. I'll let ya know if all goes well.

Forest · Post by **Forest** » Thu Jun 23, 2011 10:08 pm

All is well. Thanks for the help.