Tornado
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Here's the article comparing various R/R technoligies:
granttiller.com
For the Shunting type:
"
The very early shunting reg/recs (and even now still the very low-cost ones) are basically functionally a direct equivalent of the original rectifier and zener setup. And there is nothing wrong with this – they work totally perfectly for most people and will provide many years of trouble-free service. Just don’t upgrade your stator to a higher output one, or introduce LED lighting. For good measure you may consider riding with your headlight on, as that continual 3-4 amp current draw acts as a great place for any excess charge to go.
These units are nothing more than a pair of thyristors that are clipping the AC input from the alternator at around 14 volts. The rectifier is then converting the clipped AC supply into DC.
In this example, the ‘control circuit’ that I reference elsewhere in my diagrams is nothing more than a zener diode – it is effectively switching the rest of the unit on or off depending on the voltage in the battery.
However, the DC output was very poor quality and choppy indeed, so over the years the subsequent designs, redesigns and iterations have been refined a little – although you still see these used extensively on lawn mowers, and small tractors to this day.
The simplicity of these is very attractive, and it is the nearest you’ll get to the original rectifier and zener setup.
You should note that a battery and/or a capacitor is an absolute must, as the output needs a lot of smoothing and conditioning.
It is also worth noting that many of these are polarity sensitive – i.e., they are grounded to their heatsinking enclosure electrically as well as thermally, so can only be used for negative earth (if the flylead is red) or positive earth (if the flylead is black) This is particialrly the case for the agricultural ones, so be careful if you are repurposing one for use on your bike.
Also watch out – some of the agricultural ones are rectifiers only – they don’thave regulation built in. Confusingly, they look the same as a reg/rec, so please make sure you know what you’ve got before you fit it.
This type of unit would probably not be recommended (in my opinion) for sensitive electronics like some of the digital electronic ignitions and electronic speedos/tachos.
"
Your Bike’s Charging System - Regulator/Rectifiers and Alternators
A walk through how the charging system works on a classic brit bike with a deep dive into different aftermarket regulator/rectifiers
granttiller.com
For the Shunting type:
"
Shunting Regulator/Rectifier
In the mid-seventies and early eighties, a popular aftermarket “upgrade” was to swap the standard rectifier and zener for a combined regulator/rectifier.The very early shunting reg/recs (and even now still the very low-cost ones) are basically functionally a direct equivalent of the original rectifier and zener setup. And there is nothing wrong with this – they work totally perfectly for most people and will provide many years of trouble-free service. Just don’t upgrade your stator to a higher output one, or introduce LED lighting. For good measure you may consider riding with your headlight on, as that continual 3-4 amp current draw acts as a great place for any excess charge to go.
These units are nothing more than a pair of thyristors that are clipping the AC input from the alternator at around 14 volts. The rectifier is then converting the clipped AC supply into DC.
In this example, the ‘control circuit’ that I reference elsewhere in my diagrams is nothing more than a zener diode – it is effectively switching the rest of the unit on or off depending on the voltage in the battery.
However, the DC output was very poor quality and choppy indeed, so over the years the subsequent designs, redesigns and iterations have been refined a little – although you still see these used extensively on lawn mowers, and small tractors to this day.
The simplicity of these is very attractive, and it is the nearest you’ll get to the original rectifier and zener setup.
You should note that a battery and/or a capacitor is an absolute must, as the output needs a lot of smoothing and conditioning.
It is also worth noting that many of these are polarity sensitive – i.e., they are grounded to their heatsinking enclosure electrically as well as thermally, so can only be used for negative earth (if the flylead is red) or positive earth (if the flylead is black) This is particialrly the case for the agricultural ones, so be careful if you are repurposing one for use on your bike.
Also watch out – some of the agricultural ones are rectifiers only – they don’thave regulation built in. Confusingly, they look the same as a reg/rec, so please make sure you know what you’ve got before you fit it.
This type of unit would probably not be recommended (in my opinion) for sensitive electronics like some of the digital electronic ignitions and electronic speedos/tachos.
"
