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Hi,

I am super new to english bikes. In fact this 1976 Bonneville is my first. Prior to this it's all been Japanese bikes. So the whole Zener Diode thing is a new beast to me. I have a fairly good idea about what it does. However, my question is this. We have a new wiring harness that we are installing on the bike. The bike came with an aftermarket regulator/rectifier combo installed on it.

I have read that this will eliminate the need to use the Zener Diode? Does anyone know if this is true? If it is does it actually need to be taken off the bike? Or can it just be disconnected?

Also, what would happen if it was left hooked up?

British bikes are awesome and confusing!
thanks
 

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I am guessing you have a single phase alternator,so,the unit fitted will have 2 yellow wires, a black,and a red.The Zener wire needs to be disconnected.I would think whoever fitted the unit would have done that.
 

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If the zener still works and there's nothing wrong with it,it will cause absolutely no harm to leave it in place and still connected.
It would only do anything if the voltage became to high (which it shouldn't,if the rec/reg is doing its job).If it did help to lower voltage to the correct level,it can still cause no harm.

If you disconnect the zener wire,make sure you tape it up somehow so it can't ground out against the frame and cause a short-circuit.
 

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I disconnected the Zener when i fitted my new electronic unit.The theory being,a Zener connected, is one more thing to short circuit one day.
 

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Rambo and Pete have it covered really. If you want to know more I have put together a web page about Brit bike electrics (read Lucas) here ...

http://bike-electrics.comlu.com/index.html
Late to the party bu i have an additional question. Will this one survive the amperage on hinckley bonnevilles?
 

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Late to the party bu i have an additional question. Will this one survive the amperage on hinckley bonnevilles?
That Zenner is for bikes with the positive terminal on the battery connected to the frame, and the negative terminal connected to the ignition switch. Exactly the opposite of how a Hinkley or a Chonburi Triumph is wired. With careful wiring it should work, IF and you can see it is a big IF, the Hinkley/Chonburi has a single phase alternator (which I very much doubt).
Regards
Peg
 

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Umm.. switching polarity isnt an issue, but i forgot the new ones are three phase. Gonna keep looking then. Mine isnt made in chonburi though.
 

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Switching polarity is a huge issue. The Zener you are using must correspond to positive or negative earth depending on what bike is, or the Zener won't work. In the case of Triumph the early were positive earth. With the introduction of electronic ignition from factory they switched to negative earth & the corresponding negative earth Zener. The 3 phase used 3 zeners, negative earth

On a side note the finned heat sink looks really cool under headlamp even if there is no wiring to it.
Don
 

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Switching polarity is a huge issue. The Zener you are using must correspond to positive or negative earth depending on what bike is, or the Zener won't work. In the case of Triumph the early were positive earth. With the introduction of electronic ignition from factory they switched to negative earth & the corresponding negative earth Zener. The 3 phase used 3 zeners, negative earth

On a side note the finned heat sink looks really cool under headlamp even if there is no wiring to it.
Don
Hi Don.

I also think the pre OIF Xenor Diode Heat Sink is the coolest looking.
I picked up an example with the intention of fitting it to my 1977 Bonneville as a static display.
It means drilling into the Bottom Yoke Stem.

Do you think it's worth it?
Will I be damaging the Stem or can I reverse by filling in the holes and repainting if I need to?

To get good access I'll need to remove the mudguard, front brake and wheel, and orientation won't be ideal as the Heat Sink might end up either a little too low or a little too high.
719590
719591
719593
 

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Switching polarity is a huge issue. The Zener you are using must correspond to positive or negative earth depending on what bike is, or the Zener won't work. In the case of Triumph the early were positive earth. With the introduction of electronic ignition from factory they switched to negative earth & the corresponding negative earth Zener. The 3 phase used 3 zeners, negative earth

On a side note the finned heat sink looks really cool under headlamp even if there is no wiring to it.
Don
Im a bit of an electrical idiot but i guess just switching the wires wont do. Someone should produce a cool zenerdiode look r/r unit for the hinckley bikes! With added reliability!
 

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Hi Doc.

If you like that retro look, buy the Xenor Heat Sink, discard its wiring loom and fit it as a dummy.

Even if you could get the vintage Xenor going, it wouldn't be as efficient as a modern Rec/Reg.

Cheers

R R
 

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Hi Doc.

If you like that retro look, buy the Xenor Heat Sink, discard its wiring loom and fit it as a dummy.

Even if you could get the vintage Xenor going, it wouldn't be as efficient as a modern Rec/Reg.

Cheers

R R
Thought has occured to me, i just dont want anything to get in the way of cooling that notorious stock r/r unit..
 

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Hi Rod,

If you like that retro look, buy the Xenor Heat Sink, discard its wiring loom
The Doc's link isn't to a dry-frame Zener heatsink, it's to a Sparx reg./rec. - that's the reason for the "wiring loom" ... :)

If he wanted "that retro look", much cheaper would be to buy an actual Zener heatsink casting and work out a way of mounting it on his Hinckley's lower yoke ... :)

Xenor Diode Heat Sink
picked up an example with the intention of fitting it to my 1977 Bonneville as a static display.
It means drilling into the Bottom Yoke Stem.
The Zener heatsink mounting bracket wasn't/isn't attached to dry-frame steering stem, it's simply welded to the underside of the bottom yoke.

Will I be damaging
If you do as standard, you'd only have to grind off the weld and repaint.

worth it?
How long is a piece of string? It's your bike, ... :)

Hth.

Regards,
 

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Hi,

That Zenner
The Zener
Uh-uh; as I've posted for @Rod Rocket, the Doc has linked a Sparx combined regulator/rectifier - i.e. similar the Podtronics or Ebay Chinese Honda knock-offs I usually link.

Same as any other reg./rec., it replaces separate rectifier and Zener and, having a DC- Black wire and a DC+ Red wire, it's 'ground'-irrelevant, it'll work with either.

Hth.

Regards,
 

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Hi Doc,

Will this one survive the amperage on hinckley bonnevilles?
Probably unlikely, being intended for the low-Amps alternators fitted by all incarnations of Meriden. However, you've noticed it's single-phase only ... :(

i just dont want anything to get in the way of cooling that notorious stock r/r unit.
Ummm ... if the "stock r/r" is "notorious", I wouldn't replace it with anything from Sparx ...

Hth.

Regards,
 

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Thanks Stu. (y)

The bracket I've been supplied comes with a pre drilled hole on the section which would mate with the bike.
Being a non welder and without welding gear, I was hoping to bolt or screw the bracket into place, maybe using a tapping or metal screw.

Do you think that would do the job with minimal technical input.

Thanks

Rod
 
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