Bridgestone 200 Charging System Troubles

[Zach]

Hi, I have a 2 bridgestone 200cc motorcycles. My 1971 is having some issues with the charging system. The battery fully charged is at 12.26 volts after sitting for a week after charging. Not sure what it was charged. If I run the bike around with no lights it goes to about 12.9 volts when cruising and 12.4 idling. With the lights on it goes to 11.79 volts at idle and drops steadly while driving. After about 10 miles the bikes lights are dim and it doesn't have enough voltage to run anymore. Not sure where voltage drops to of long trips. Short 1 mile trip voltage was just about 11 volts. I'm not sure 100% how the charging system works on these. I know the recitifier has been changed at some point but has the same number of wires as my 1970 and looks to be setup correctly. Any help would be great. Thanks, Zach

[BSOrion]

Zach,

I had a similar issue with my 71 Mach II.  The issue was the rectifier which I did replace.  However, some other common culprits are the generator (check for AC readings of the three phase wires... I think they were yellow, brown, and blue), the main switch, and ground in general.  I would bet on the rectifier.  I went through 4 used and they were all bad. 

It's not much but I thought I'd chime in.

Orion

[Zach]

Thanks, Orion. I guess I will start some test tomorrow. Looks like the 1970 may donate some parts soon.

[Zach]

I checked rectifiers on both bikes. Both seem to be shorted. The one on my 70 is original, the one on my 71 is aftermarket. Any ideas? I checked ebay and no luck on a rectifier, anybody know of something I can make work. I don't mind changing the wiring. I just want to be able to ride at night.

I just thought this might help. The one rectifier I have is a shindengen sh222-12 rectifier. It looks like it came factory on a kasaki, it may just not be wirid up right. Anybody know anything about swaping these onto bridgestones?

[reed]

Zach
Give BSORION a e mail he will tell where he got his rectifier from  they where not much money etc.
Thanks.
Steve.

[OldSwartout]

You need one of these:

http://www.newark.com/semikron/skd-25-16/bridge-rectifier-3ph-150a-1-6kv/dp/88K1981?in_merch=Popular%20Products&in_merch=Popular%20Products&MER=PPSO_N_C_EverywhereElse_None


Bolt it to something that will act like a heat sink.

<edit>
This is probably better, it comes built into a heat sink.  There are several choices on ebay for three-bridge rectifiers.
http://cgi.ebay.com/3-Phase-Diode-Bridge-Rectifier-100A-1000V-SQL100A-New-/180666386009?pt=LH_DefaultDomain_0&hash=item2a108e4659

[BSOrion]

I would go with the 3-phase rectifier that Karl has the link for  (the second link).  You need 3-AC inputs and even though you can pick up a very simple silicone bridge rectifier for a few dollars, they're short an AC terminal.  Of note, I'm not an expert so be aware that these newer rectifiers are more efficient so if you are running the bike a lot, just check to make sure the battery isn't getting hot, indicating overcharge.  Best of luck.

Orion

[Zach]

Ok I ordered the one in the second link. Once it gets in I will need some help wiring it up. I apreciate everyones help with this.

[Zach]

I installed the rectifier yesterday and put about 50 miles on the bike with lights on with no issues. Thanks for the help everyone.

[Jeff Bar]

Zach

Please tell us how you hooked it up. since it has 5 terminals  Tks  Jeff Bar

[Zach]

I just hooked positive to the battery, negative to the chassis ground, and the other 3 wires up to the diode part of the rectifiers.

[BSOrion]

Right on Zach!  Glad to hear the new rectifier worked out.  The one I have works but I think the style you have now is what I'll eventually go with for my 200.

Orion

[Zach]

The recitifier I have works but it is big. I had trouble getting it in without extending wires.