Topic: need help with new regulator/rectifier

[jamesb]

i had bought a bunch of bike stuff this was in it i was going to use it on my 75 chopper build to clean up my santee electric box i know what wires are what except for the black ones this was supossed to be for a cb550? but i'm going to (or might) use it on my 1975 cb750 engine and are these worth the time of day to use.any help would be appreciated thanks
jimmy

[GammaFlat]

The aftermarket combined regulator/rectifier units are generally shunt type regulators which are harder on your alternator than the factory regulator.  If you can get your hands on a factory regulator, use it.  The regulators on these bikes are very robust, tune-able and refurbish-able.  The rectifiers on these bikes are kind of anemic.  They're easily "blown", so think about replacing it with a home grown one.  I'm not sure what you've got there (Oregon maybe?).  Is there anything on it that would identify it? 

[jamesb]

there are no markings anywhere the guy said he got it for his 550 it was a 74 i just thought it would clean up my santee box a bit so it wasn't all cluttered.all my original stuff works

[GammaFlat]

Relocating your electronics is no problem (Santee box).  Which electronics you use is kind of another matter.  There's a thread around here about a "hunderd" miles long that talks about alternatives to the factory regulator/rectifier combination.  The regulator used was from a Ford pickup and the rectifier was home brew.  I believe with the Ford regulator, you are in a "shunt" arrangement.  Lots of folks have had good luck with them (and I've experimented with them) but I've changed directions and will be using the factory regulator. 

The rectifier is relatively easy and cheap to build (essentially 6 diodes, some wire, a heat sink and connectors).  I'd be more than happy to help however I can.  As a matter of fact, I have the parts to make a "run" of replacement rectifiers but haven't been able spend enough time on the bench to build them. 

The bottom line is, if you don't know what you got.. you don't know what you got.  Somebody may have tried to transplant those parts from a later model bike or they may be appropriate but you may not know how to wire it.  hmmm..  I say build your own rectifier and find a factory regulator and mount it all in your Santee box. 

[dave500]

use that combo unit you have just for the rectifier part of it,then use a little electronic bosch "re57" regulator,too easy.


above 3000 rpm its always on 14 volts,it runs at just over 13 with the head light off idling.

[Ricky_Racer]

More info, Dave! Nice little unit. More info, please!  RR

[jamesb]

yes more info please i'm digging this set up

[dave500]

these are an external regulator that replaces the tin box type on early bosch alternators,it was less than $30,has the three pins and is clearly marked with d+ and d- etc so its easy to hook up,i might even tidy up this wiring one day.

i like good earths.

[jamesb]

found what i was looking for hondachopper.com had exactly what i have thanks for the reply i actually found it from a old post that was put on here.

[dave500]

make sure your combined rec/reg didnt come from a bike with a permanent magnet alternator,,these regs wont work,,they more or less just dump excess voltage to earth and if used on an electromagnetic field type alternator like ours the field is just running flat out all the time,you can use just the rectifier part of these however and use another regulator,i cleaned up my three year old mess a little.

[dave500]

i dont care who uses what rec/reg setup,heres mine in action,its been the same for a few years,it charges alright,the boyer ignition unit i use only pulls 2 amps with a pair of .6 ohm coils in series,that might give me an edge,the headlight is a h4 55/60 or 60/65 i forget.

[ValleBR]

Hi, Dave.
A friend of mine has a 1973 Honda CB 550 F and is experiencing rectifier/regulator problems. He ran into this post of yours and asked me to contact you (since he doesn't speak English) to try to obtain more information on how he could get these parts you mention in your replies in the post and, if possible, he'd like to rely on your assistance to solve that problem.
He has been unable to find that RE57 regulator here in Brazil. No one he has contacted so far knows how to do that using other types of regulators - indeed, he found something, but that was too expensive.
He's desperately seeking help. His bike does not generate enough voltage to maintain the battery, and keeping an idle at a minimum of 1,500 rpm is not good for the bike, he says. Neither can he ride at 2,500 rpm most of the time here because the city is relatively small and full of traffic lights, with no long streets to maintain an appropriate rpm for this motorcycle - and the climate here is hot and humid (the Amazon).
I hope you can read this and help him somehow.
Thanks in advance.
Cheers.