Topic: Electrical "issue" on my 400four

[billdramp]

So gang... my 400four has been draining my battery. I am absolutely a newb at electrics...  besides hooking up harnesses and such, as far as trouble shooting or using a  multi meter etc. I have not the faintest clues.

The symptoms are... the battery takes a full charge. I run for a few days perfectly... and then the battery starts getting low, and the bike, of course, will not start. I charge the battery again. Repeat cycle.

Last night I was riding home and I realized my headlight was not on... I pulled over to check my fuses. I reached in the fuse box, and one fuse was scalding hot and burned my hand. It did not fix the headlight issue. I turned the ignition on and off a few times and the headlight came back on.

Can anyone help me troubleshoot this, or just help point me in right direction... I am willing and eager to learn.

Cheers from Portland,

Billy

[keiths]

It sounds to me like you have at least two problems. Your switch and every connection in your bike.
Start by cleaning every connector in your headlight bucket and move on to under your side covers and every other connector you can find. I used emery paper and electric contact cleaner. After cleaning, apply a small amount of dielectric grease to each connector. Your headlight switch may also need cleaning or repaired. Don't forget to clean your fuse holders and tighten them up a bit. Make sure the fuses are full length, someone may have put the wrong size fuse in. If this fails, you may want to buy or borrow a meter and narrow down the problem.
Good Luck.

[HondaMan]

It's possible that you have a shorted (or partially shorted) rectifier. This is a "Buck Rogers" finned-looking thingie under the side cover, near the battery. To see if this might be the culprit, unplug the rectifier (it has a connector on it that must be pinched to release the little clip first) and make sure your battery is charged. Then, repeat your earlier experience of touching that hot fuse you found, after repeating the ride, as best you can remember. If it is no longer hot, then it may just be that device: if you can gain access to a volt-ohmmeter, then we can tell you how to test it. It might just be this simple! 

[333]

How old is the battery?  Does it havce enough water in it?  Do you have a multi-meter?

[oldbiker]

If a fully charged battery lasts a 'few' days then it is likely to be a charging problem. Usually dirty connectors can account for this but you must remember that these bikes don't charge very well below about 3,000 rpm so try to keep above this figure.
The hot fuse is another common one again caused by bad contact at the fuse holder. Make sure the fuse clips are clean and TIGHT.

[riktaboy]

Have you changed anything on the electrical system.  New Headlight, electroninc ignition, newer trun signals?  Theses are all gonna tax a 400's electrical system more.  Secound you need to get a volt meter if you don't already have one (Harbour freight has them for a reasonable price, Napa does not).  Get one of these asap and start using it, it will save you ours of frustration and time, well worth the investment.

[burmashave]

As somewhat of a side note, if you are very new to vehicle electrics, you may wish to check out some of the Electrics FAQS for primers on electrical basics for SOHC/4's, selecting and using a multimeter, etc. See especially Bodi's Basic Electrical Fault Finding - Start Here! for some good basic info., and also Basic Electrical Theory and Multimeter Use for the scoop on selecting and using a multimeter.