This article discusses in detail how to rewind a 1996 XR600 to boost the magneto capacity to drive a 55W lamp without draining the battery. Since little to nothing has been done with the XR design from 1991 to 1998, identical methods are likely applicable to these model years. The author has not checked the similarity to XR400 designs, although the technique may work well with XR400s and XR600s of earlier model years.
Honda made the 1996 XR600 with little generation capacity. Dual sporting the bike really requires this upgrade since the magneto can barely drive a 35 Watt lamp without it, and no respectable street bike gets sold with a 35 Watt headlight. Experienced night riders also know that 55 Watt lamps are mandatory for any serious off road forest exploration!
Fortunately, Honda made the XR600 so that its windings could be augmented very easily. It is a simple upgrade and the process is explained in detail.
Finally, these instructions have been proof-tested. This exact procedure was used by the author on his own vehicle and has been in service for months.
I recommend that you read the complete instruction set before embarking. Instructions sometimes require several lines and are not perfectly chronological.
List of materials required:
- High temperature heavy-insulated 18-gauge magnet wire. If you’re green on how to get this stuff, it’s easy. Just call Allied Electronics at (800) 433-5700 and request part number 214-3574. A 1-lb spool should cost $10 and will wind around 3 to 5 bikes. Ask for equivalent wire in other brands if they quote you high.
- 3M 2216 or 3M 1838 epoxy. The author merely recommends these industrial epoxies because they can take the heat and oil and will adhere to plastic insulation in the magnet Wire. There are others.
List of Tools required
- Soldering gun.
- Wire cutters.
- Wire strippers.
- Metric 8mm hex socket.
- Needle nose pliers.
- Metric Allen wrench and 10 mm wrench to pull side cover from bike.
- Remove the left side cover. Figure (1) shows the 1996 XR600R after this step. Don’t forget that the magneto cavity is wet, and you will dump over a quart of oil in this operation.
- Pull the magneto housing from the side casing by removing the three hex head bolts that mount it to the side cover. Also pull the sheet metal retainer clip that captures the wiring in the side cover.
- Examine the magneto body to determine the routing of the magnet wire you will add. Figure (2) shows the configuration. Note that there are 12 “cores” pointing radially in the magneto. Each active element has many wraps of magnet wire where a voltage is induced by the passing magnets in the flywheel. The windings at nearly 10 and 11 o’clock in Figure (2) power the ignition. The lower 4 windings that are eclipsed by the source wiring to the Vehicle are lighting coils. The other six cores are unwound. You will wind the magnet wire about these.
- Begin winding the magnet wire as shown in figure (3). It is IMPORTANT that you alternate the direction of the windings between adjacent cores. Note that the author left 8 inches extra wire at the 6 o-clock winding, and weaved up to the 12 o’clock core to start winding. Wind this core clockwise looking inboard, and then wind the 1 o’clock core counterclockwise looking inward. If you fail to alternate in the sequence no damage will occur, however, the voltages generated by the adjacent windings will not add to one another but instead subtract.
- Wind all the empty cores until the magnet wire stacks to create a radius that is slightly less than the top of the core itself. You may even choose to skip the last core since you will be generating plenty of power. The author used all the windings although they are not really required. Note that the voltage generated is proportional to the total number of “turns” in the magneto.
- Clip the magnet wire with 8 inches of extra length past the last winding.
- Splice your magnet wire in series with one of the lighting coil source lines. This is the point to pay attention since a couple of instructions are critical for proper function.
a) Note that the lighting coil from Honda follows the same alternating clockwise/counterclockwise polarity. You must splice your wiring in series with the existing Honda lighting while following the alternating sequence initiated by the Honda coils. I suggest that you follow the Honda lighting wires (they are visible and unwrapped) through the wrapping progression from an end that you choose arbitrarily. Note that you have two leads from your magnet wire. You will cut the Honda lighting wire and connect each of your leads to the two Honda ends created by your cut. If you violate the sequence of the Honda leads and swap your wires in reverse polarity, no worries, you will merely get the difference of the voltages generated by your coils and the Honda coils. In other words, you will know that you must go back in and swap the lines.
- Cast epoxy over the windings you added. Use an epoxy that can take the heat and oil exposure, and that can bond to the insulator plastic. I used 3M 2216 industrial epoxy. Make sure to degrease before bonding, with a plastic-safe degreaser. I used a citrus degreaser, and then some rubbing alcohol, and a shot from an air compressor.
- Magnet wire is insulated with a clear coat. You must strip the insulation at the point you wish to solder. I recommend soldering at your splice. Insulate it using the same cloth insulator used by Honda. Also, remember not to scrape away the insulation on the windings where it is needed.
- Verify your connections after soldering and check that you haven’t shorted to the side cover.
- Remember that this wiring sees lots of vibration, heat, and oil. Just strain relief and insulate as Honda did. It’ll work like that.
- Reinstall the magneto into the side cover and on the bike.
- Connect the wires from the stator to the regulator input. The stator generates AC only and the polarity of these wires doesn’t matter.
- Do a nasty trail at night for me!
Ride on, mother
Senior Mechanical Engineer