The ignition coil on my 1982 Honda Nighthawk CB450SC tested bad, so instead of replacing it with a used part from the 80's or a cheap coil from china, I decided to upgrade. After finding a post on the Hondatwins forum about using a coil from a 99 Chevy Cavalier, I decided to go that route. Some of the information on the forum post was incomplete or hard to find, so I put together my own parts list with readily available products. I decided to make this post for anyone else looking to do the same upgrade.

Parts list:

Standard Motor Products DR39T Ignition Coil (for 99 Chevy Cavalier) available on Amazon

\~1 meter of copper core ignition cable (MUST BE stranded copper core, NOT suppression core/resistance core/carbon core) available on Amazon 

2x XB05F spark plug boot caps (5k ohm) available on Amazon 

2x Spark plug wire crimp terminal ends and boots, available on Amazon 

2x Small male spade crimp terminals (preferably waterproof)

Small section of 3/4 inch 22 gauge metal hanger strap, for mounting the coil on the frame

Cap head hex bolts:

1 m6 x 16

1 m6 x 25

1 m6 x 35

1 m6 nut

1 lock washer

Tools needed:

Wire stripper

Crimp tool

Hex key

Tin snips

Wrench/ratchet

Plyers

1. Modifying the signal wires: Make sure your spade connectors are small enough to fit in the slots on the back of the ignition coil. Mine were too wide, so I trimmed them down with a tin snips and some sandpaper. Cut the small black and yellow wires off the old coil, leaving as much wire as possible and the factory connector that plugs into the motorcycle wire harness. Crimp the small spade terminals onto these wires, and plug them into the slots on the back of the coil. It doesn't matter which wire goes in which slot. You could also use liquid insulation or plastidip to seal the crimp connections.

3. Making the bracket: Cut a 3.5 inch long section of metal hanger strip, and modify it with the tin snips and plyers to get it to fit while avoiding the spade connectors and wires. Use the pictures for reference.

2. Making the new spark plug wires: Cut the 1 meter copper core spark plug wire into 2 sections, both a few inches longer than the factory wires. Note that one wire should be longer than the other. For me, one wire ended up being 17.5 inches long and the other was 21.5 inches. On one side of each wire, strip the insulation about a half inch from the end, twist and fold over the stranded copper wire, and install the crimp ends making sure that the copper wire is crimped securely. Slide the rubber boots over the crimped ends. Next, strip the other ends of the wires a quarter inch from the ends and fold the copper wire core to the side. Screw the 5k ohm spark plug caps into the wires, making sure the screws inside form a solid connection with the stranded copper wire. Now would be a good time to measure each of your new spark plug wires with a multimeter to ensure a solid connection and 5k ohm resistance from end to end.

4. Installation: Bolt the modified end of the metal hanger to the connector side of the coil using the lock washer, nut, and 25mm hex bolt. Bolt the other mounting hole of the coil to the front threaded hole on the frame using the 35mm hex bolt. Bolt the metal hanger strip to the rear threaded hole on the frame using the 16mm hex bolt. Plug the white connector into the factory wiring harness connector. Route your spark plug wires and plug them onto their respective spark plugs, it doesn't matter which wire goes to which spark plug.

Finished! The coil sits nicely in front of the gas tank and the metal hanger bracket is not visible. The new coil is reported to have stronger spark, less wasted fuel, and better starting, power, and a smoother running engine across the RPM range. I hope this helps anyone else looking to do this upgrade.

Upgrading the coil on my 1982 Nighthawk 450