At least one, and perhaps more of us here at the the Jalop not only fantasize about cars on a minute-by-minute basis, but also find time to squeeze in wet dreams about transportation of the two-wheeled variety. While the world of motorcycles can seem foreign and dangerous to the cage driver (that's what we call you douchebags when we're on the bike), it's actually safer than you'd think. The vast majority of motorcycle-related injuries are caused by operator stupidity. Another huge chunk of those injuries are due to some cager not seeing you in the worst possible moment. With that in mind, updating the signaling and lighting system on your motorcycle isn't the worst way to spend a few bucks, improve the bike's looks, and maybe keep your sorry ass off the pavement.
I must mention that this presentation won't be 100% representative of a stock upgrade, since the bike in question has been upgraded previously. While it doesn't have the grody three-inch taillights from the 70's, it still has the original incandescent electronics. (Cagers take note: There's no reason this won't work the same way on your "car.")
Opening up the bike, you can see that the previous upgrade attempt wasn't exactly performed by an organized electrician. Wires everywhere, poorly grounded, weak connections (gah! wingnuts!?) — not a pretty picture. The first step in every wiring project is to know where you are, then you can ascertain where you're going. For this, a shop manual for your bike is crucial. ("This is your manual. There are many like it, but this one is yours, Your manual is your best friend. It is your life. You must master it as you must master the feeler gauge...") Get a handle on the wiring diagram and trace out the relevant circuits as identified by wire color code. On old steeds, the turn signal system is driven by a tiny hamster thermal flasher.
These thermal flashers work by passing electricity from the battery, through a switch and into a thermal winding, which will expand and reach a contact. The Juice then passes through the incandescent element, where the charge is used then grounded, and the process restarts, since the wire cools at this point. Unfortunately, this process doesn't work so hot (hah, pun) with LEDs. The light emitting diode doesn't draw enough current to restart the process, so it will light one time, then stay on. What's the solution? Electronic flasher switch!
Electronic flasher switches have relays and stuff, so you most likely need to have a signal source (the switch circuit) and a power source (battery). I got the snazzy one with a micro so I could re-utilize most of the original circuitry. For this case, I was able to run the turn signals, flashers, brake lights and running lights together because the voltage of each is distinct, and will light the LEDs at different intensities.
When installing wiring, make sure that all splices are at least well crimped at the connectors, if not soldered together. To be neat, only run as much wire as you need. I like to use heat shrink tube to keep everything together and wrap the spilts and joints in electrical tape. You can pick all of this stuff up in any big box store's electrical aisle. Just make sure you slide the tube over the wire bundle before you make your permanent connection or you'll be cursing your deity over the sorrows of rework. After buttoning everything up and testing the result, put everything back together and enjoy your handiwork. Now watch out for those cagers.
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