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CB77 Charging System...

Charging System, Wiring, Lighting
nmrtian Member
Posts: 2
Joined: Thu Aug 25, 2005 12:11 pm

Re: CB77 Charging System...

Post by nmrtian » Thu Aug 25, 2005 12:36 pm

I ran into this problem many years ago. Selenium is no longer used in semiconductor components partly because they deteriorate with time and use and partly because they are just not as efficient as silicon components. I made up a replacement rectifier using four silicon top hat style power diodes and the improvement was big enough that I could use the electric starter again. The little bridge rectifier from RS is probably just what you need as long as it is well heat sinked. The worst that will happen is that it will get too hot and fail if it gets too hot. If this happens, you may want to go to a real electronics store and see if they have a rectifier and heat sink that is more robust.<br /><br />A trick for the mean time -- turning on the lights also kicks in a part of the generator that is not normally used although the lights use up pretty much all of the extra power. However, if you turn on the lights and then set the headlamp dimmer switch midway between high and low, the headlight will be off but the generator will still be fully on. All of that extra power then goes to the battery.<br /><br />As for the new rectifier producing &quot;more pure&quot; DC, well, that's just not true. <br /><br />
Vince Lupo wrote:<br />More news regarding my charging system. We (my mechanic, really) replaced the battery with a better quality one and it seems to be holding at 12.70 volts. I also found out that in order to actuate the 'third phase' of the stator, the headlight needs to be on. As well, I recently attended the Canadian Vintage Motorcycle Group's annual show/rally in Paris, Ontario (and I rode to it from Baltimore, MD!), and I met a fellow who suggested that I replace the selenium rectifier with a teeny rectifier from Radio Shack (he showed it to me and it's just a little 1&quot;x1&quot; square with a few wires coming out). He said that this type of rectifier produces a more 'pure' DC current. Does this make sense??? Anyhow, the bike seems fine at the moment, but I may give this new rectifier business a shot and see what happens. Thanks ever so much for your replies!<br /> <br />

kustommusic Member
Posts: 585
Joined: Sat Sep 11, 2004 6:44 pm
Location: Goshen Indiana

Re: CB77 Charging System...

Post by kustommusic » Thu Aug 25, 2005 4:55 pm

nmrtian, That is great information. Thanks for dropping in and educating us! Please feel free to do so any time, I know I need it! Steve Greer

Tom W. Member
Posts: 33
Joined: Thu Jul 14, 2005 9:58 am
Location: So. CA

Re: CB77 Charging System...

Post by Tom W. » Fri Aug 26, 2005 9:33 am

Oregon Motorcycle Parts sells a Silicon based rectifier on ebay for $23:<br /><br /> ... iewItem<br /><br />It seems like a reasonable price especially for an electrically-challanged guy like me. I have not dealt with the seller so I don't know if it works.<br /><br />Tom

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