A handy tool for working out how much current is used by various components is the 305M Fuse Buddy Tester by IES. I've had one for years and sold buckets of them when had my tool business.
The unit consists of a digital display and a couple of foot lead which terminates in a plug body. The unit is plugged into the fuse socket which serves the device and uses the same fuse as was used for the device.
Pull the fuse, plug the fuse into the fuse socket on the side of the ammeter's plug body. This provides the same fuse protection as was present before and acts to complete the circuit within the plug body. Next, turn on the ammeter and plug into the fuse socket in the fuse box. Turn on the power and the ammeter will display current flow in that circuit with polarity indicated.
Mine is a 20 amp which is sufficient for bikes like the KLR and since it is polarity dependent, one can determine the direction of current flow in the circuit such as whether the battery is charging or not.
You will have noticed there are two models, the 305M which is what I use and the other which is intended for ATC/ATO fuses. Since most people use the ATC or ATO (same thing just different terms), they often make the mistake of buying that model. Mistake because the 305M is for the mini fuses but check the fuses side by side and you will see that a mini fuse will plug into an ATC or ATO fuse socket. Not idea for longer term but means that the mini fuse model 305M will work for both fuse types.
Another trick is to add some longer wires and jumper clips to a mini fuse socket. This way you can plug your Fuse Buddy into the socket, poke in a 20 amp mini fuse into the ammeter's fuse socket and clip the fuse holder leads into the circuit to be tested. Handy for checking things like: how much does that electric vest draw?, or how much is the charger charging the battery?
Make a mistake and pop a cheap mini fuse. No problem! One can also use smaller value fuses if that makes sense for testing.
I have an amp clamp ammeter, some good multimeters which measure current, shunt type ammeters and several direct connect ammeters but this little character is very handy. Price is under $30.00 and have seen a 30 amp version which would be my choice now.
If one wished, a temporary install to a bike would be simple using one.