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Discussion Starter · #1 ·
Does anyone have any experience with replacement regulators? A few people are mentioning the Oregon Motorcycle Parts combo rectifier/regulator for permanent magnet alternators (PN VRRPM2-HCB). Are there other options that anyone's discovered? I'm reading 16 volts at 4,000 rpm on a 1974 CB450 so I'm assuming I need to be buying something soon.
Theoretically, shouldn't a lot of other (more modern) motorcycles' regulators work? Or is Oregon Motorcycle Parts the only game in town right now?
 

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jdeforestacome said:
Does anyone have any experience with replacement regulators? A few people are mentioning the Oregon Motorcycle Parts combo rectifier/regulator for permanent magnet alternators (PN VRRPM2-HCB). Are there other options that anyone's discovered? I'm reading 16 volts at 4,000 rpm on a 1974 CB450 so I'm assuming I need to be buying something soon.
Theoretically, shouldn't a lot of other (more modern) motorcycles' regulators work? Or is Oregon Motorcycle Parts the only game in town right now?
There are a couple of other suppliers for modern, sealed regulator/rectifiers but I don't have any experience with them. The combination regulator/rectifiers are typically quite a bit more than the individual parts. I've got an Oregon Motorcycle rectifier on my 450 and I'm happy with both the product and the support/conversations I've had with the owner.
 

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Discussion Starter · #3 ·
Thanks. I'd normally just do the combo thing from OMP, except for the fact that I just bought one of their regulators at the beginning of the summer (and yeah, amazing customer support - great folks) and the $92 price is a tough one for me.
Dans Motorcycle Repair Website (http://www.dansmc.com/electricaltesting.htm) has a reference to opening them and cleaning them; ever heard of that working on these?
Here's the real question, maybe - How do you know if a regulator will work on any given charging system? Shouldn't all regulators do pretty much the same thing, meaning its more a matter of finding something you can mount and get connected correctly to the harness? Is there any reason why I shouldn't just assume any 12V DC regulator work?
 

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JD..... You would think that, but NO!.....It has to be electrically "matched" to the specifics/needs of the charging system....
 

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Discussion Starter · #5 ·
Well now that's frustrating...
Thanks a lot. I found a used one to experiment with breaking it open to see what happens and will repost with some results.
 

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I believe you'll just find a "gated diode" or what is also called (I believe) a SCR.... It's a single semi-conducting component (somewhere between a diode and a transistor from what I've been told).......Even Honda calls it a "pointless regulator"....(No lie!....That's what they call it....)
 

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Discussion Starter · #7 ·
Funny. I didn't get it apart (didn't really try too hard) but, on second thought - - maybe these regulators actually are adjustable(?) I got it off the bottom of the air tube and there's no obvious way to take it apart, but I hadn't known there was a little screw on there. I got the screw out and sprayed some contact cleaner in the hole and cleaned up the screw with some steel wool. It had been bottomed out, so I set it bottomed less 180 degrees. Voila - - maybe. I only tested it once, but it only reads about 13.5 volts at 3,000 rpm. It used to read 15V at 3K and 16 at 6K (which is why I decided I needed a new regulator). Anyway, maybe it's good news... I'll have to test it again when its warmer.
 

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Discussion Starter · #8 ·
new numbers, after a 20-mile ride in ~75 degree weather, at battery:
headlight off - 12.5V @ 1200 rpm, 14v @ 3k rpm and 15v @ 4k rpm
headlight on - 13v @ 1,200 rpm, 13.5v @ 3k rpm and 14v @ 4k rpm

much better than when i did this before i messed with the rectifier, when it showed 13 at idle, 15 at 3k and 16 at 4k.

something that doesn't show up in those numbers is that i pulled back into my garage after riding it and it idled for probably 3 or 4 minutes while i found my voltmeter and the extra key to open the seat. i hooked it up and got the 12.5v reading right away. after i got the 15v reading at higher rpm, though, and closed the throttle, the readings didn't return to the original 12.5 right away. in fact, they never did. it may be an idiosyncrasy of my voltmeter (its an older digital one from matco) but it counted down about a tenth of a volt every second or so. it seemed to bottom out around 13, with the bike idling, so that's when i turned on the headlight to get readings with that turned on.

anyway, the short version of this story seems to be that either the screw on the rectifier actually does something, or spraying the cleaner into the box made a difference, because i'm not sure the bike or voltmeter could really show a placebo effect. and if the light's on all the time (which it should be anyway) the volts seem to cap out at an okay level.

in any event, maybe for my own curiosity, i'm thinking i might wire in a cheap volt gauge and ammeter and mount them on the handlebars just for fun. in the meantime, though, looks like i'm saving some money.
 
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