Topic: Electrical Problems on 1980 CB650C

[jonah562]

Hello all.  I am hoping someone can point me in the right direction.

I bought this bike used with no info.  Sealed the gas tank, cleaned the carbs, replaced the battery, put in new fuses and plugs.

When I got it, the fuse for the horn was missing and the main fuse link was rigged with a piece of wire.  Also the ignition switch has been turned with a screwdriver. After replacing the fuses and getting the bike running, I noticed the horn was not working and the battery seemed to be draining.  I replaced the horn and all appeared well.  About 5 miles into a ride to get an inspection the bike died at a stop light.  I tried to start it but the battery was almost dead.

I tried to jump it but it wouldn't stay running.  Then the horn began to sound and will not stop with the ignition on. Today I yanked the fuse to the horn, charged the battery and it started right up.  Drove for about 3 miles and the bike started to die.  Pulled over and lost absolutely all power.

I am looking for a place to start... alternator, ignition switch, voltage rectifier? Any advice is appreciated.

Jonah

[SCJIM]

ill admit im no expert but...

what it sounds like is a massive short somewhere or some jerry rigs you have to un-rig.

i owuld start with the wiring itself. checking for splices or bare wire.

get into it and really check the integrity of the wiring.

then once your confedent with that check the components,
bulbs in all of the instrument cluster, turn sigs., breaks then fuses

then after that check the charging system

heres a quick test for ya...

charge your battery,   then with the battery by itself with nothing attached
meter it and see what the voltage is. this should bearound 12.82 VDC

then install it in the bike and meter the battery again with the key off
it should test the same or "verry" close like (12.81 VDC)

if there is a large drop in voltage then you have a drain on your battery that shouldnt be there

next test is turn on the key and meter again
without the engine running it should be in the 12.81 12.82 VDC area

with the engine running the charging system is in play at this time and well the volts should go UP from there.


let us know how you make out

[cb650]

Sounds like the elec gremlins have a hold of your bike. They are atracted to things that havent been properly fixed.  Just keep fixin things. Look at you main harness and make sure it hasnt been spliced into.  Clean the plug to the alternator as many people have probs with alt going bad. I havent on any of mine. On the gold wings of the era they say it was the plugs going bad shorting out the alt.



                                Terry