Electrical Wire Upgrade
To help the voltage regulator and the entire charging system, an easy and inexpensive upgrade is to replace old, small, worn and sometimes corroded stock BMW wires with a set of upgraded heavier wires you make yourself. Here's how:
The Best Wire to Use
For the best wire, go to a marine supply store and look at their selection of bulk wire. They will have wire as thin as 22 gage and as thick as 6 gage, with costs ranging from $.11 to $.49 per foot. The marine wire is rated for 600 volts, is oil-water-gasoline resistant, and is made with very fine multiple strand wire. The finer the wire used in the multi-strand wire, the more flexible the wire will be to handle and install, which is important when working within the tight confines of a motorcycle.
If you can't find a marine supply store, auto parts and hardware stores also carry quality multi-strand wire at reasonable prices. I have used this material in the past and it works well but is not as flexible as the marine grade wire.
While you are shopping for wire, check out the supply of connectors. For the large 6 or 8 gage wire, you will find heavy battery terminal type connectors. For 10 and 12 gage wire, female or bolt style connectors are easy to find. Since you want to crimp and solder all electrical connectors, the plastic covered ones are a pain to use. Instead, I buy regular uncovered connectors and slip a piece of