High Output Voltage Regulator - All 1970-on Airheads
This Beemershop High Output Electronic Voltage Regulator fits all 1970-on Airheads and upgrades the old mechanical relay type regulators used in the 1970's. It is sometimes all you need to get more voltage to the battery, keeping it properly charged. The stock BMW regulator tends to choke down the charging system output too much, especially on 1981-on models. This regulator is part of our High Output 600 watt charging system but it works equally well with the stock charging system to allow more charging voltage to the battery. The output is set to mimic the factory BMW Police Regulator which is no longer available.
How does it work? The stock BMW Airhead charging system is an electromagnet rotor type system. The more voltage allowed to the rotor via the brushes and rotor slip rings, the more output is generated by the stator windings. The regulator governs this voltage to the rotor to keep charging system output in proper range. In fact if you “full fielded” the rotor by unplugging the regulator and connected a jumper wire between the two blue wires that are side by side in the regulator connector and measured voltage at the battery, it would just keep climbing to such high voltages it could fry your bulbs. We like to see abut 14.2 volts at the battery at 4200 RPM with the headlight and other consumers turned off. You normally cannot achieve those numbers with the stock regulator, but our high output regulator will get you there.
Note: your battery must be healthy and in a full state of charge or output testing at the battery will give misleading numbers.
If you are running additional electrical consumers such as a heated vest, heated grips, driving lights and so on, you can easily draw more current than the stock charging system can handle, resulting in an under-charged battery. In these applications we highly recommend our 600 Watt charging system which is the gold standard for high output aftermarket charging systems.