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Discussion Starter #1
Hi,
I'm relatively new to motorcycles, but my younger brother left a partially dis-assembled 1973 Honda CB350 at my parents' place when he moved out West a few years ago. I'm attempting to get her back in running condition. The project was going pretty well until the other night. The gas tank and fuel lines have been off of the bike for a couple of years and we're cleaning and painting the tank.
I put a new battery in the bike and re-assembled the hand controls (my brother had planned on swapping the handlebars, but never got around to it.) I replaced a blown bulb in the tail light, and replaced the turn signal relay (the signals weren't flashing). I turned the key and all the electrical worked great! The starter and horn worked, the turn signals were working, and the headlight and taillight were functioning. Then, a few hours later I tried to show my wife what I'd accomplished. I turned the key and... NOTHING! No power to anything. I charged the battery overnight, and still nothing. I replaced the ignition switch, and still nothing. What happened to the electrical system on this bike? What else should I check/replace? I know I'm a newbie, but I'm at a loss on this one.
I was hoping to get the tank and fuel lines back on the bake this weekend and see if we can get her running, but that's not going to happen until we sort out this electrical problem.
Please help.
Thanks.
 

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I think there is a main fuse located near the battery on that bike, did you check that?

Edit: Reference number 25 - 15A fuse
 

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I located the fuse. Sure enough, it was blown. I've replaced it and we're back in business! Thanks for the help! :thumbsup:
 

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Ok guys, new problem. I got the bike reassembled and tried to start it for the first time. I actually got it to crank over. However, there was a loud pop and hiss from under the fuel tank and it began to smoke (also from under the tank). I hit it with the fire extinguisher as a precaution. Also, since this incident the tail light comes on and stays on when the key is turned on. I had to leave for work, so I haven't had a chance to take the tank off and have a look. Any thoughts?
 

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I've been studying the wiring diagram. Would a blown ignition coil be consistent with what happened? That's my current hypothesis.
 

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Something is shorted out, probably a bare wire or connection touching the frame or engine. That's the likely cause of the fuse blowing and the brake light acting erratically.
 

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Wow, that's shot. Were it me I would probably just find a stock replacement on eBay or from a breaker.

I'm sure there are aftermarket Dyna coils available. On one of my old cb450s I used a couple of very generic ignition coils, much like this:

[ame]http://www.amazon.com/OEM-5195-Ignition-Coil/dp/B000CSW79C/ref=sr_1_3?ie=UTF8&qid=1338747460&sr=8-3[/ame]

I did have to come up with a way to mount them, though.
 

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Similarly I just purchased a 71 CB350 that I am slowly getting back into shape. I have an electrical issue and thought I would see if anyone could point me in the right direction. My neutral indicator light, tach lamp, speedo lamp and turn signal indicator light are not functioning. All other electrical components seem to be functioning fine. I checked the bulbs and they are good. Any ideas on where to start troubleshooting this one. Thanks.
 

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Just a guess, but pull the headlight and check the electrical connections in the headlight housing. A bullet connector may have come unplugged. In the absence of that issue, it may be the key switch itself.
 
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