Topic: electrical fun...

[jason teamshralp]

okay so i got my carb problem fixed/figured out. After a short ride the other day i put the bike in the garage and then went back to it the yesturday to ride again and when i turned the key to on. Nothing. No idiot lights, no head light, nothing when i hit the starter button. Checked the Battery, okay. Hooked it up to a charger, still nothing. Only thing i didn't try was to kick start it. but even if that started i still would have no lights.

Anyone have any tips where to start?

[troppo]

What bike?
I would guess a blown fuse

[jason teamshralp]

i thought of that. i checked them and they looked okay but im going to buy fresh ones anyways.

[fastbroshi]

  I'd look at the plastic connectors on the electrical panel.  There's this one on mine that even when connected through the metal base plate, it can still wiggle quite a bit.  So it's not that far a stretch to assume it might have worked it's way loose somehow. 
  Also, those blades will come out of the connector, if you felt motivated enough to clean them up.  I just went through the electrical system on my '77 550F and did this.  Takes some time, but worth the peace of mind.

[bwaller]

If your bike is a later model with the ignition switch on the triple clamp, check the switch base. Sometimes rerouting wiring puts a strain on that base connection in the switch and you can lose all power.

[burmashave]

I'd start with a mulitimeter. There's some good posts about electrical troubleshooting in the Electrics FAQ. Also, what year and model?

[jason teamshralp]

I'd start with a mulitimeter. There's some good posts about electrical troubleshooting in the Electrics FAQ. Also, what year and model?

78 cb550k

[HondaMan]

Keyswitch unplugged itself?

[Jonesy]

I had the same issue with our '78 550. The terminals in the switch base had come loose, and even though I peened the copper rivets to tighten them back up, they corroded underneath.

When you turn on the key and get nothing, try wiggling the electrical connector and see if the juice comes back on. (If you do this at night, you might even see blue flashes through the white plastic switch cover, like I did!). If this gets the power back, order a new switch base and cover from the Honda dealer. They make them aftermarket, but some folks have complained about how they fit. Honda made improvements to the switch assembly (I outlined them with pictures in another post) to beef up the contacts, and they now solder the rivetted connections prone to loosening and corrosion. The parts cost about $35.00 total. I replaced them and have not had any problems since. It also fixed the 1.5 volt drop I got through the switch....

If you try it and confirm you do need the switch, I can dig around for the part numbers.

[UnCrash]

Fuses can look intact while all the solder ends up running out of one of the ends on overheating.

Check them on the Ohms setting with a multimeter.

[fuzzybutt]

Keyswitch unplugged itself?

+1   this used to happen to my 74 750k alot when the switch was on the tree

[jason teamshralp]

it's the switch. I went and pulled, pushed the wires under the triple trees and the lights pop on and off. What is the best way to fix this? Replace it? or jimmy rig it?

[Gordon]

it's the switch. I went and pulled, pushed the wires under the triple trees and the lights pop on and off. What is the best way to fix this? Replace it? or jimmy rig it?

If it's just loose, plug it back in. 

[jason teamshralp]

it's the switch. I went and pulled, pushed the wires under the triple trees and the lights pop on and off. What is the best way to fix this? Replace it? or jimmy rig it?

If it's just loose, plug it back in. 

I have tried pushing it back in but it doesn't seam to want to stay plugged in. Anyone know the part number for the plug? or any tricks to make it stick?

[Jonesy]

There's a tang on the switch cover and a loop on the harness connector that engages it. The harness connector is likely not available alone from Honda. Look to see if the tang/loop are not broken.

[HondaMan]

I had the same issue with our '78 550. The terminals in the switch base had come loose, and even though I peened the copper rivets to tighten them back up, they corroded underneath.

When you turn on the key and get nothing, try wiggling the electrical connector and see if the juice comes back on. (If you do this at night, you might even see blue flashes through the white plastic switch cover, like I did!). If this gets the power back, order a new switch base and cover from the Honda dealer. They make them aftermarket, but some folks have complained about how they fit. Honda made improvements to the switch assembly (I outlined them with pictures in another post) to beef up the contacts, and they now solder the rivetted connections prone to loosening and corrosion. The parts cost about $35.00 total. I replaced them and have not had any problems since. It also fixed the 1.5 volt drop I got through the switch....

If you try it and confirm you do need the switch, I can dig around for the part numbers.

Good observation, Jonesy! I need a new one on by 750. Last year, the keys FELL OUT of the ignition on the way home one night, got home and couldn't turn off the bike! I wouldn't say it was old, but...I ordered one of those aftermarket ones from an eBay store (no time to go to the Honda shop 35 miles from here), and the wires are smaller gauge, lightly soldered (I fixed that), and the connector cheesy. Just to keep gasoline $$ from killing me, I hardwired it into my 750 for the duration of the season: I need a good one. I think I'll mail order one from Honda, now...at least, my new job is only 8 miles away!

[mark]

Keyswitch unplugged itself?

+1   this used to happen to my 74 750k alot when the switch was on the tree

+ another. Hooray for cheap parts bikes with stock switch brackets.

There's a tang on the switch cover and a loop on the harness connector that engages it.... . Look to see if the tang/loop are not broken.

tang and loop don't need to be broken to not hold worth squat.   p.o. had extended the switch wires(even matched colors!) - just not quite enough.

.....I need a new one on by 750. ....I ordered one of those aftermarket ones from an eBay store ...and the wires are smaller gauge, lightly soldered (I fixed that), and the connector cheesy. ...

hooray again for cheap low mileage parts bike with matched locks and a working switch with keys.

[DJ_AX]

Sounds suspiciously like the problem I'm having right now. hmmmm....
will have to check that when I get a chance.

[jason teamshralp]

i used some zip-ties to fix it but it still didn't fix it 100%. anyone have one of these? or a place to buy one?

[Jonesy]

You can buy the plastic cover 35102-431-007 (H/C 092530), and the contact set 35101-422-007 (H/C 092529) from any Honda dealer.

[jason teamshralp]

i found a few on ebay for around $30.00 and also found that http://crc2onlinecatalog.com/Index_Main_Frame.htm
 has them for $28.00 + $6.00 shipping and I have used these guys before.

this kind of works out cause the only key i have is real thin and kinda bent. I guess i'll be killing two birds, replacing it.

I though of something else while looking around. What would it take to relocate the key, and eliminate the pilot lights, and gauges?

[Jonesy]

Here's the post where I compared the old vs. new parts:

http://forums.sohc4.net/index.php?topic=19056.msg198941#msg198941

[DJ_AX]

....turns out my issue was caused by the positive wire just as it leaves the terminal on the battery was severed... and hidden underneath the rubber cover. I was on the verge of pulling the whole harness!