Regulator Rectifier

jdizon

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Can anyone recommend a good source for purchasing a new regulator / rectifier for a 1980 xs400. MikeXS doesn't seem to carry any. Not sure if there is even a combo reg/rec available?
 
I paid just over $50 including shipping for my rr38 from alibaba.com its like amazon or ebay except it is an eastern free trade site. If you did not have a combo reg/rectifier before then you might have to find a creative way to mount it. It is going to be bigger and may interfere with wiring routing. Also the old hardware can be reused but in most cases just too short or if mounted under the battery box then a bit too long.

My bike is almost done, just charging and testing the battery and getting ready to set advanced timing and sync carbs. I may be posting mine up for grabs this summer when my kinks are sorted. I found amongst the 3 types of voltage regs available 2 have male clips and one is female so I suggest you go by what your wire harness is asking for. The combo reg/rectifier has a male clip with no ground (it shares regulator ground), and the mechanical adjustable v reg also has a male clip. My 78E has a male clip on the harness so I decided to go with the Solid state v reg which has a female connector.
 
I have used this site a lot also alibaba.com mainly for ordering electronic stuff like tablets and phones ,security cams and other things.So far Ive had decent luck with them.
 
RR38 has been recommended by Drewpy in the past, I just checked that website, seems that they want min order of 50 pieces. May be they meant 50 pieces of dollars? :)
 
Hi. I need new regulator/rectifier for my 1980 XS400 2a2. Does xs400 Dohc regulator/rectifier work with older sohc bikes?
I found one shop in Europe that sells them. There's three choices: RR32, RR38, RR33
https://www.electrexworld.co.uk/cgi-bin/sh000001.pl?WD=xs400&PN=RR32.html#SID=439
https://www.electrexworld.co.uk/cgi-bin/sh000001.pl?WD=xs400&PN=RR38.html#SID=439
https://www.electrexworld.co.uk/cgi-bin/sh000001.pl?WD=xs400&PN=RR33-Regulator-Rectifier-Yamaha-XS400.html#SID=439

Do they actually have any differences? The RR38, what I thought would be the best fit, is out of stock. Is there any chance that the RR33 or RR32 would work?
I live in Estonia and found one from here for XJ550 1981 (like the RR32) for 40€. All the wires are same, but not sure it will work.
 
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I contacted the shop and early next week the RR38 will be back in stock. Is it the right one for my bike?
 
The regulator/rectifier was already changed. Both my connectors from regulator/rectifier are male connectors, but there isn't such choice. Im not sure If someone already changed connectors or not.
The shop technician told me the RR33 is low side switched field. RR38 is high side switched field. I dont know what is the difference.
 
Somebody is pulling your leg, the field get switched on BOTH ends. Gets switched ON when charge is low and OFF when charge is high. On ALL alternators.

Look here, all 3 of those units use the same colored 7 wires, 3 white, 1 black, 1 red, 1 green, and 1 brown. Ignore the plastic connectors. I'm thinking all 3 units use the same basic regulator just wiring connectors change. If you look close at your connector you can take a fine pick and unsnap the detent to remove every wire from your connector to then use yours on the new unit done the same way. I've done it countless times and how you get back to the correct connector needed. If not cut leads and splice.

the 3 whites are stator leads, you can mix them up as far as which one goes where
red is battery power
brown is battery power with switch turned on
black is ground
green is to the alternator field

Look close at the reg pics and they all 3 have those same colored wires.
 
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Okay, things are getting more confusing for me. :D

Is it worth trying xs400 dohc regulator/rectifier?
Found cheaper one near me.
 
If you haven't checked your alternator for working you may be wasting your time.If the 'new' part is bad too you have done nothing. The DOHC part does use the same wiring to it and appears it will work. Plug may be different and puts you right where you are now.

If you are having that much trouble with it then pay someone to do it. One mistake in the wrong place and you can have a fire there.
 
Somebody is pulling your leg, the field get switched on BOTH ends. Gets switched ON when charge is low and OFF when charge is high. On ALL alternators.
They're referring to which end of the field coil wire gets switched.
Early model regulators switch the positive supply voltage, with the other field coil going to ground, while later models switch the ground connection and the other field coil wire goes to +12v.

You need to match the regulator year compatibility to your model year.
Even then a lot of retailers don't realize that there are two types of regulators on XS400s.

The DOHC regulator should work fine for your bike, but as AMC said you'll need to match up the connectors. Or rewire it yourself.
 
It makes absolutely no difference at all which end of the field coil gets switched in the operation of the field, either end will work the same. The alt when it rotates will still work the same, all it knows is if there is magnetism in the field or not.

The only difference would be how long the regulator lasts, they last longer when switching the ground and why all automotive computers do that now. Switching grounds lowers the amount of potential amp the switching transistors have to deal with.

Now OP is dumping in the possibility (post #14) of not needing a rectifier reg at all, he picks what is likely the wrong part for what he is buying now. Says he wants a reg only but is trying to buy a rec/reg and the wrong part.

OP, if you have a rectifier separate on that bike you better know it, you are making things worse. if you need what is in post #14 then your choices at the first post you made (post #5) are ALL wrong, they include the rectifier in the unit.
 
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It makes absolutely no difference at all which end of the field coil gets switched in the operation of the field, either end will work the same. The alt when it rotates will still work the same, all it knows is if there is magnetism in the field or not.
It makes a difference because a ground switching regulator won't work when plugged into a bike wired to switch the positive supply, and vice versa.

K3ith I know other members have used the RR38 but I do not recall which year of bike they had. It looks like the RR33 probably has the right connectors but also doesn't say which models it is compatible with.
The Mike's/Rick's one should work fine.

Any of the above could be made to work with any model of bike if you are willing, able, and understand the changes required.
I think a direct swap is probably in your best interest.

As AMC points out you would also be replacing the rectifier but that's not an issue at all.
 
It makes a difference because a ground switching regulator won't work when plugged into a bike wired to switch the positive supply, and vice versa.

K3ith I know other members have used the RR38 but I do not recall which year of bike they had. It looks like the RR33 probably has the right connectors but also doesn't say which models it is compatible with.
The Mike's/Rick's one should work fine.

Any of the above could be made to work with any model of bike if you are willing, able, and understand the changes required.
I think a direct swap is probably in your best interest.

As AMC points out you would also be replacing the rectifier but that's not an issue at all.

Thank you!
Think I'll try out the dohc regulator. That's the cheapest and closest one to me right now. If it's possible to make any of these work with any model, then I'm sure my electrician can wire it up right when I take the bike to him.

AMC, the separate regulator and rectifier on my bike has been changed by one of previous owners to one unit regulator/rectifier. The separate regulator was not taken off the bike and was just ''hanging'' on the bike, not connected (electrician tested it and it's not working). I just put the link up to show what regulator was originally on, I thought maybe it helps you choose which regulator/rectifier I need. I'm not gonna buy this one.
Sorry about the misunderstanding.

Am I right: with the low-side switched like RR32 (dohc regulator) it should be connected like this (one wire from field coil to ground and one to regulator): https://i.imgur.com/xChoS34.jpg?2
And with high-side switch like the RR38 should be connected like this (both wires from field coil to regulator): https://www.xs400.com/attachments/xs400_1979_wiring_diagram-jpg.3854/
 
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Then you need to not show pics of one that will not work, it is a disservice to you.

'It makes a difference because a ground switching regulator won't work when plugged into a bike wired to switch the positive supply, and vice versa.'

True, I was not carrying my thinking out far enough and made too general a statement that was true in and of itself but not realistic as to the fine points of this thread. On the ground switching one you have to sever the ground point and carry the connection back out as power to the to the field instead. Harder to do if the reg grounds right to the case, you would have to remove that and insulate the mounting point to carry out another wire for power instead. I've done it on solenoids and horn circuits before but not a reg. It might be easier to leave the internal ground and simply add a relay there to flip the power. I used to do that same thing to Fords that used the expensive IRCM and CCRM integrated relay boxes at +$250 each by patching in a relay to replace one of the bank that had gone bad to say kill a/c or the fuel pump. The mod cost maybe $10-$15 in parts to do and lasted forever.

A grounding regulator will be hooking up to field power from somewhere else after the load, not the regulator, and the other type will have a freestanding ground outside the reg to end the field circuit.

Beyond that almost any of those rec/regs will work if somebody knows how to wire them. Here's one for you being some of the bikes have separate rectifiers easily gotten to. If you can get to the stator where all 3 loops tap together on one end you can pull another new wire off that wye connection and add another pair of diodes to get an extra 10-15% more alt output out of the alt with no penalty at all. You end up with 8 diodes instead of 6. Pretty much most cars do that now and I have converted 6 diode ones that do not to then be the same way. Like getting a high output alt for nothing.
 
On the ground switching one you have to sever the ground point and carry the connection back out as power to the to the field instead. Harder to do if the reg grounds right to the case, you would have to remove that and insulate the mounting point to carry out another wire for power instead.

A grounding regulator will be hooking up to field power from somewhere else after the load, not the regulator, and the other type will have a freestanding ground outside the reg to end the field circuit.
Thanks!!
If you have time to explain a bit more how to exactly do it, would be great.
English isn't my native language so its hard to understand things sometimes.
 
I did that work on older types with removable covers to be able to get at the guts. When they pour epoxy on top of things to seal the modern chip types then it becomes impossible to do. I've removed certain types of potting compound but most are impossible to work with without damaging underlying components.

Meaning you do the work outside the unit, if your electrical guy is as good as you say he can easily do that.
 
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