O
Oppad
Guest
Something I picked up from a KLR mailing list. Should be of interest to other KLRistas' who are considering upgrading lights and other voltage eaters (that is, apart from Hein who has already done all the aftermarket stuff):
Quote follows:
The KLR has an "ac magneto", unlike a car alternator or a modern motorcycle alternator, it does not have field windings. It has permanent magnets, and the only voltage control is for the regulator to dump excess voltage to ground. It produces more power when you spin it faster (high rpm), and MUCH less when you don't (idle).
So, when you draw more power than the magneto can produce, the regulator doesn't try to compensate by giving more power to the field windings (and burning them out). The output voltage simply drops until it is lower than 12v, at which point you (with no warning unless you installed an aftermarket gauge) begin draining your battery.
The bike will run perfectly well, the light slowly get dim as the battery flattens, and if you stop the engine you don't have the juice to crank the starter.
My experience was a battery in excellent condition will run another 55w on top of the stock electrical load, in mixed city/open riding, without discharging. If your battery is weak, or not fully charged to begin with, you have less capacity to play with.
You can save some power by changing the tail/brake light to an LED (get a really bright one like dual-star sells, not the cheap bulb-size ones), eliminating the license plate illuminator (or rigging leds), and changing the instrument backlights with LEDs. In total you can scrounge up perhaps another 24w of power.
If you are only using the aux lighting on the highway, at high rpm, you can get away with more.
Quote follows:
The KLR has an "ac magneto", unlike a car alternator or a modern motorcycle alternator, it does not have field windings. It has permanent magnets, and the only voltage control is for the regulator to dump excess voltage to ground. It produces more power when you spin it faster (high rpm), and MUCH less when you don't (idle).
So, when you draw more power than the magneto can produce, the regulator doesn't try to compensate by giving more power to the field windings (and burning them out). The output voltage simply drops until it is lower than 12v, at which point you (with no warning unless you installed an aftermarket gauge) begin draining your battery.
The bike will run perfectly well, the light slowly get dim as the battery flattens, and if you stop the engine you don't have the juice to crank the starter.
My experience was a battery in excellent condition will run another 55w on top of the stock electrical load, in mixed city/open riding, without discharging. If your battery is weak, or not fully charged to begin with, you have less capacity to play with.
You can save some power by changing the tail/brake light to an LED (get a really bright one like dual-star sells, not the cheap bulb-size ones), eliminating the license plate illuminator (or rigging leds), and changing the instrument backlights with LEDs. In total you can scrounge up perhaps another 24w of power.
If you are only using the aux lighting on the highway, at high rpm, you can get away with more.
