was: 2005 klr 650 now: klr electrical usage
Posted: Mon Oct 31, 2005 6:28 pm
Ken, Other interested Listers,
Since this seems to be of interest to quite a few folks, I just got back
from my shop where I did a few electrical tests on MY bike. Here's what
I did. I used a Craftsman digital multimeter number 82139, which has a
10 amp range and goes on sale pretty regularly at Sears for about $19. I
pulled the side covers and seat so I could get to the top of the battery
and the white wire coming off the positive post. I hooked the meter up
for the 10 amp range and connected it in SERIES at the bullet connector
for the white wire. Please remember I've done a few electrical changes
to my bike so you may get a different reading on yours. But these
readings should be close.
- With the headlight off, key on, I got a reading of 1.51 amps. I think
this only taillight & instrument lights.
- With the headlight on, key on, I got a reading of 5.43 amps. Low beam
drawing 3.92 amps.
- With the headlight on high beam, key on I got a reading of 6.10 amps.
High beam drawing 4.59 amps.
- With the headlight off, key on, fan on, I got a reading of 3.83 amps.
Fan drawing 2.32 amps.
- With the headlight off, key on, horn blowing, I got a reading of 3.08
amps. Horn drawing 1.57 amps.
- With the headlight off, key on, Dual Star LED Brake light on, I got a
reading of 1.93 amps. LED brake light drawing 0.42 amps.
- My heated grips are on a different circuit and I got readings of 1.55
amps and 2.75 amps.
- My Gr8 Design heated vest pulled 2.21 amps.
- I didn't test my heated gloves.
My battery was reading about 12.05 volts. Yes I know I'm on the verge of
battery failure. Thank you very much. : )
The factory manual says the alternator puts out 14 amps @ 8,000 rpm at 14
volts. Remember the conversion is amps x volts = watts. So 14 amps x 14
volts = 196 watts at 8,000 rpm @ 14 volts
The KLR engine I understand uses a magneto type system so that doesn't
put a drain on the battery or charging system. So when my bike is
running down the road here's what I suppose I'm using electrically:
Normal instrument lights, tail light (remember I have a dual star LED
rear light, I suppose the stock uses maybe 0.8 amp [8-12 watts] more) and
headlight (mine is stock at 55 watts). That adds up as follows:
- Normal instrument lights & tail light = 1.51 amps @ 12.05 volts
- Headlight on low beam = 3.92 amps @ 12.05 volts
TOTAL = 5.43 amps @ 12.05 volts
Converted to watts that is 5.43 amps x 12.05 volts = 65.43 watts
- If you are running a stock high beam headlight, that uses 5 more watts
and increases use to 70.43 watts.
- Apply the brakes and you are using an additional 0.42 amps or 0.42 amps
x 12.05 volts = 5.05 watts.
- Blow the horn and it takes an additional 1.57 amps or 1.57 amps x 12.05
volts = 19.63 watts.
So, I suppose a KLR running down the road without extra lights, heated
grips or other accessories, but running high beam, applying the brakes
and blowing the horn is using about 95 watts. This should probably leave
(I'm guessing here) about 100 watts for other stuff if you're having a
real good day and your charging system is working well. But, since the
brake light and horn are not used all the time you are probably really
only using about 70-75 watts*. For most folks that probably leaves a
solid 100 watts to play with. But your battery better be in good shape
and you must be keeping the rpms up and running long enough to charge the
battery after cranking. Someone on this list I think recently stated it
takes about 1 minute of charging for each second of cranking. If you are
using all your charging capability to make extra electrical stuff work,
your battery won't be getting charged.
*If you have a stock tail/brake light you should probably add 8-12 watts
to the total.
Why is watts a better number than amps for this? The amperage draw of a
device will change based on the voltage used. The watts will remain the
same. An example is a light bulb. A 55 watt headlight at 12 volts will
draw 55 watts / 12 volts = 4.58 amps. The same 55 watt headlight at 14
volts will draw 55 watts / 14 volts = 3.93 amps. So... converting amps
to watts will probably give you a better number to work with.
Last thing for this post. Electricity only works well with clean, solid
connections and wires large enough to handle the load. In other words, a
dirty or corroded connection will reduce the ability of the electricity
to do what you ask of it. You can do your part by making sure
connections are tight and clean. Making sure wiring you've had added to
your system is of a size large enough to do the job and connections are
well made is important. Keeping the fluid level in your battery at the
correct level will help your battery perform as you'd like it to.
Please let me know how to make this easier for you to understand.
Jeff Saline
ABC # 4412 South Dakota Airmarshal
Airheads Beemer Club www.airheads.org
The Beautiful Black Hills of South Dakota
75 R90/6, 03 KLR650, 79 R100RT