Newly Designed Voltage Regulator for '72-'75 Kawasaki H2,
1973 H1D, 1974 H1E, 1975 H1F, and 1976 KH500
5 year warranty

Aluminum Housing Price: $139 each
Hand Welded and Finished Stainless Housing: $169 each


Regulator with Aluminum Housing


Regulator with Stainless Steel Housing

  • New design uses modern components for precision regulation

  • Made in the U.S. by and for Triple owners
  • Maintains very accurate battery Voltage
  • Allows use of stock type, AGM sealed, or gel sealed batteries without overcharge damage
  • Internal 22,000 uF capacitor allows use without a battery at all, if desired!
  • LED indicates regulator operation
  • Eliminates the need for the stock external rectifier between regulator and battery
  • Low loss Schottky rectifier diodes and HexFET® Power MOSFET components eliminate need for heat sink
  • Housings made from 6061-T6 aluminum with printed ABS top, or hand fabricated from 304 stainless steel
  • Both models have identical components and the same five year warranty!


Brand New Design

This is a brand new design, specifically for the Kawasaki H2 and 1973-1976 H1 (H1D, H1E, H1F, and KH500).  It addresses several shortcomings of the original unit, including poor regulation, the need for an external diode, and the need for a battery or large capacitor for proper operation.  It is housed in a beautiful brushed 304 stainless steel housing, and fits in the original location perfectly.  The wires have bullet connectors installed for an easy plug-in installation.

The Original Regulator

The original Kawasaki H2 and H1D regulators didn't hold the Voltage very steady.  The H2 manual says that the "average voltage is held down to 15 ± .5 Volts".  Testing in our shop shows that if you're running without your headlight and other loads on, that 15 Volts can become considerably higher.  Even with the losses of the required diode between the stock regulator and the battery, 15 Volts is pretty far on the high side of OK for wet (non-sealed) lead-acid batteries, and requires regular checking of the battery's electrolyte level.  It is too high for sealed batteries.  Most sealed lead-acid batteries are the AGM or "starved electrolyte" type.  AGM stands for "Absorbent Glass Mat" (sometimes "Absorbed" or "Absorption".)  This type of battery has fiberglass mats between the lead plates, and just enough electrolyte (acid) to completely wet the mats, but no extra.  An AGM battery is designed to re-absorb gasses produced during charging, but has a vent to release excess pressure in the event the battery is charged too quickly.  If charging is controlled by the stock regulator, there will definitely be more hydrogen and oxygen produced than can be re-absorbed, causing gas venting and loss of electrolyte.  This will slowly ruin the battery.  How quickly the sealed battery fails is a function of how much riding is done, engine RPM, and electrical load.  The external diode between the regulator and battery was needed to block reverse current from the battery through the stock regulator, which otherwise would discharge the battery in a matter of days.

The New Lakeland Super-Regulator

Precision Regulation

This newly developed regulator is designed to accurately maintain alternator output Voltage, and to compensate for outdoor temperature.   At 75 degrees, the charge Voltage is set at 13.7 ± .1 Volts.  This is a safe "float" Voltage for conventional batteries, as well as sealed types.  Since our H-series triples do not have high current devices like starter motors, there is no need for a "bulk" or high-current initial charging stage.  Keeping the battery Voltage at a steady 13.7 allows it to float until a little power is needed while at idle with the headlight on, for example.  Once the engine speed increases, the battery is recharged gently at 13.7 Volts.  The regulator also has the correct temperature coefficient, so that at low ambient temperatures the output Voltage is slightly higher, and at high temperatures it is slightly lower.

High Efficiency

Our new regulator uses modern components in a modern design, and not only holds the output Voltage very steady, but is very efficient.  Heat generating losses due to Voltage drops in the rectifier diodes and shunt transistor are minimized through the use of state-of-the-art components.  The rectifier section is a full-wave bridge using high-current Schottky diodes, which  have a forward drop of less than 0.4 Volts under load, less than half the drop of conventional silicon diodes under load.  The shunt transistor is a highly efficient HexFET® Power MOSFET, and in this application has a drain-source drop of only 0.15 Volts.  The result is that this regulator produces less than half the heat that the stock unit produced, and doesn't need big heat sink fins on its housing.

LED Shows Regulator Operation

On the end of the regulator housing facing up when installed (stock position, H2), there is a yellow LED to indicate regulator operation.  When the LED is off, all alternator current is being passed through the regulator to the battery and/or lights and accessories.  When the LED lights, the alternator is producing more power than needed, and the regulator is acting to reduce it.  The brighter the LED, the more the alternator's output is being reduced.  This gives the user a visual indication of proper regulator operation, and also a feel for the engine RPM needed to maintain battery charge for a given load (headlight, turn signals, etc.).

LED off, showing full alternator output to electrical system
LED on, showing alternator output being controlled

Capable of No-Battery Operation!

The output section of the regulator includes a 22,000 uF capacitor, built right in.  It's big enough that for this regulator design, it eliminates the requirement for a battery, without using a separate battery eliminator capacitor.  Many users prefer having a battery, so the lights and horn work if the engine isn't running, and some states require this ability.  Also, if you're using sensitive electronic devices that run on 12V, you should probably use a battery.  But if you prefer to not have a battery installed, you can run without one, without fear of damaging the regulator or ignition units.  Our tests show that with a properly functioning alternator and no battery, an engine idling at 1500 rpm will produce enough output to run a headlight and tail light at approximately 11-12 Volts.  At normal road engine speeds, you'll have a full 13.7 Volts steadily.

Eliminates the Separate External Diode

Kawasaki added an external diode between the regulator and the battery to stop the regulator from draining the battery while the motorcycle is parked.  Our regulator does not need this diode.  We even recommend not using it, since it adds some Voltage drop.

Five Year Warranty!

This Voltage regulator is very rugged, and outperforms the original units in every way.  We will repair or replace this unit, or refund the purchase price (at our option), if it fails to perform properly as a result of defects in materials or workmanship, within five years of the date of purchase.
Please note:  The yellow and black wires on this unit are 9" long.  The red output wire is 11" long, about 2" longer than stock, to allow connection without the external rectifier.   Custom wire lengths are available at no extra charge, for the H1 or non-stock installations.  Custom lengths normally do not delay shipment, but in some cases may add a few days.  Please specify custom wire lengths at the time of ordering, if needed.

Also note: All regulators now come with new reproduction Buna-N rubber 2-pin connectors as shown one the aluminum regulator above.


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