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Discussion Starter · #1 ·
I upgraded my rectifier on my bike using the radioshack rectifier upgrade, which i've used on both my bikes, and was very happy with it. however, I am only running a 4ah battery on one of my bikes and didn't want to trust the stock regulator to keep my battery from being cooked, so i started looking at upgrades.

I saw the single unit upgrades from charlies place and oregon parts, but they are bit out of my price range. I noticed that one of the units was identical to a reg/rect I had installed into an old riding mower. that unit had only cost me $45, so I started looking at those. after a bit more research I found a good, small unit. I was lucky and got mine in an auction for $10, however all the other units i've seen online sell for right around $25-30.

the unit is typically used for Kohler or John deere engines, its rated for a 12v15a system. these honda twins (as far as i know) only get about as high as 8a, so the 15a is plenty.

here's a link to one example.

http://www.ebay.com/itm/REGULATOR-RECTI ... 1881wt_568

the kohler part number is 25-755-03

now for those of you who have already upgraded to the radio shack rectifier, installing this will be a breeze, as it only has three terminals. AC1(yellow) AC2(pink) and battery+ (red or red/white) and it grounds out through frame, or you could bolt it on using a ring terminal. basically you just unplug the radio shack unit from the wiring, plug this one in, and remove the stock regulator.

here's a comparison shot.


and here's a shot of my wiring.


now, the hard part will be mounting it. for me, I installed this on my cafe 500t, so it was all custom mounted anyway. I would think it could almost be mounted where the stock regulator went however, only being bolted on with one bolt.

and while i installed this on my 500t, it will work for all honda twins with a 12v system and this kind of charging system
 

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I will be following suit shortly, I'm adding one into my 450 project since its time to start working on the wiring. Thanks for writeup. :)
 

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Any updates on how it works? I constructed mine as follows.

Took the stock mount for the rectifier and BENT the ears down to give a nice flat spot. I tried the original mount area for the regulator under the battery box but the holes wouldn't match up and the new unit was just barely too long and would have gotten into the air filter rubbers as well. SO I just glued a couple of bolts in those two holes.




I then tested the old holes and found that if I mounted it with them the new unit would run into the fender and the frame brace so I cut the excess ears off and drilled new holes higher in the mount.





Fits pretty well, have not got my bike running yet so I've yet to see if it works.

Test fit again with new wires, I am using the rectifier harness as well, I did ground the green to the unit.



And here it is ready to go in


I have yet to get the bike running so I don't know if it works but it is pretty simple to install. I did rework my wiring harness to remove the regulator wiring as well.
 

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Discussion Starter · #5 ·
seems to work great so far. i've put probably over 100 miles on the bike since then and the battery hasn't needed charging or maintenence, so its keeping it right in the voltage range.

also, nice mod on the stock mounting spot, that looks perfect. I was wondering how to get that in there neatly with the back mounted terminals, but that looks like the way to go.
 

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I'm having to tear into my 360 here soon, she's having a carb issue that will make me have to remove the radio shack rectifier conversion to get to it. I will be moving it over to one of these shortly I think.
 

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Possibly a stupid question, but as I'm a novice (at best)... What do you do with the old regulator wires?

I prematurely replaced my rectifier, thinking I could replace the regulator just as easily... but no one sells a stand alone replacement regualtor for the old RS21 that was on the bike.
 

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hamlet76 said:
Possibly a stupid question, but as I'm a novice (at best)... What do you do with the old regulator wires?

I prematurely replaced my rectifier, thinking I could replace the regulator just as easily... but no one sells a stand alone replacement regualtor for the old RS21 that was on the bike.
I just removed them from the harness, you will find they are just spliced into the main wires from the rectifier. Or just tape them up and stash them out of the way.

HerrDeacon said:
So what is the benefit of running this one instead of the Radio Shack one? Is it mainly for when running a low ah battery?
Perry, the benefit is it is a combined Rectifier and Regulator in one small package for a quarter of the price of say Oregon's combined unit. They use more advanced technology as well, better able to make a nice smooth output instead of the choppy one the stock system provides.
 

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Thanks very much for the advice. As a newbie, I would have never guessed that I could just unplug something and not need the wires... I Will be looking into this when I return from vacation. Amazing how re-labeling it "John Deere" regulator/rectifier instead of "motorcycle" regulator/rectifier changes the price from $25 to $115+...

What gets done with the green wire out of the harness?
 

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You can leave the green unhooked or just stick it under one of the mount bolts, THis unit grounds to the frame and the Green is the universal ground for wiring harness, it is common through the entire thing.
 

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This is great. Just bought one.

I'm a newb with all this.. are there any good instructions anywhere on removing the Regulator?
 

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So just to make sure. Have any/ all of you guys done this ( viewtopic.php?f=53&t=6185 ) mod to the same bike? Figured it would be nice to do both of them if others have with no problem
 

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I'm wiring my 450 to remove the extra circuit completely and I have modified the stator to combine all of the windings into one output and I'm using the above regulator.

The mod you linked to is a GOOD idea either way as it will keep your battery up no matter what you are doing for the most part. Batteries are much better these days and can take more of a beating (charge) that those of 30+ years ago. If you are going to use a modern style regulator and rectifier unit then it makes sense to give it as much juice as the bike can give it.

I even did the charging mod to my 360 but that really only comes into play when the lights are OFF. It will be getting one of these units here probably the next rainy day I get.
 

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I apologize if this is a simple question

but what are the specifications that I would be looking for if I were searching for a reg/rectifier?
anything that says 12v15a? I see some auctions up for reg/rectifiers, but not sure if they'll work for my cb360

thanks
 

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Noob here looking for a little clarification on this upgrade if you guys don't mind. If I'm understanding this correctly, the regulator/rectifier mentioned in this thread can replace BOTH the little aluminum box marked 12V (regulator?) and the larger orange square finned thing (rectifier?)

Is this correct?
 
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