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Discussion Starter · #1 ·
Hey everyone,

I've been restoring a 71 CB450 and the first time I started it up I wasn't getting much of a charge output. So I went ahead and did the charging mod where you plug the two stator coils together bypassing the headlight switch to get full charging output all the time. I did what everyone recommends and just plugged the white and yellow wires together in the headlight bucket.

But this just made the fuse blow right when I turn the key on. Not sure what I did wrong. I even used a continuity tester on the wires to make absolutely sure they were the ones coming from the stator.

I'm also confused why this is supposed to work. Everything I've read about this mod says these wires normally get connected when the headlight switch is set to HIGH. But every wiring diagram clearly show's that these wires get connected in the low and neutral states.
 

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Are you sure you didn't confuse the white low beam wire from the handlebar switch with the white with yellow side on the insulated cover? Mine is together now and those wires are under the tank so I can't easily see them, but IIRC that's what you're looking for
 

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Discussion Starter · #3 · (Edited)
I'm pretty sure it was the correct wires. The solid white wire that comes from the switch goes directly to the headlight, I made sure to leave that one alone.

But yesterday I put the wires back where they're supposed to be and finally got the bike idling correctly and rode it for the first time! It felt so good to finally get it running on the road. So I checked the charge output once again and suddenly I'm getting adequate charge. 12.6-12.7 volts at 1200rpm and when I rev it it goes up to around 13-14 volts. Not sure what I did but problem solved I guess?

I'm still not sure why the wiring shorted though, or why this mod is supposed to work in the first place. Oh well.
 

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It's about the mod bypassing the need for the headlight switch to be on to kick in the additional alternator coils, making them functional all the time. The connection for that additional charging goes through the headlight switch for the days before we had to run headlight on all the time, so in essence if your headlight is always turned on then they're already in use.
 

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I did this mod last week. I joined the white and yellow wire where they come from the back of the motor {I also added a combined RR unit}

The bike charges well and the charging tops out at exactly14.05 volts reliably.
 
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