How to Wire a Lightning Sprint Engine
So, you decided to buy a lightning sprint? You made a good choice. They are fun to race and a great class with competitive racing. They are raced around the country and tune some of the best drivers, that have become today's household names. But when you get a car, some of them aren’t wired very well. Because the motors and electrical systems are out of street bikes, it can be a little intimidating.
When the engines come out of the bike, the wiring harness has a lot of extra wires for things that aren’t needed in racing applications. There are lots of companies that offer a service to have the wiring harness “cut down”. You can do it yourself if you are savvy with wiring diagrams and have a few rolls of electrical tape, but I find it easier to spend the money and leave it to the professionals who do it for a living.
We are going to focus on the wiring of all the things that are going to be separate from the harness. These will be things like all the switches, fans, fuel pumps, and wing sliders. When you look at your dash and see all the wires, don’t be scared. There is a lot there, but once you decipher it all, it's really not that bad. One thing to keep in mind (at least in my opinion) is that there is no good way to make everything look exceptionally clean when you are wiring. There is always going to be a bunch of wires, and it is hard to find the right path to run the wires, but you can make it look good if you are aware of the right tools and accessories.
I run a 07/08 Yamaha R1, but everything said in this article will be applicable no matter what engine/injection combo you run. On the wiring harness, there will two main wires that feed into your switches. One is power all the time and one is power in the wires that feed power to the rest of the main harness. Check your wiring diagram to trace these wires and make sure they get wired correctly. I like to use a Longacre Switch Panel that has multiple switches; it makes the dash look really clean. The panel that you will need has more switches than what this article will use, but it works out well.
So, when you get the switch panel, it will have one switch that is to the left of the starter button. I like to use this switch as the main power switch. The wire coming out of your harness that feeds the main power will go to the “off” side of the switch. And the wire that comes from the harness that feeds the rest of the harness will go to the “on” side of the switch. I like to mount the switches upside down. This way you will flip the switch downward to power is on. This way if you hit a big bump on the track, you will have gravity working in your favor and the switch will not accidentally switch off.
In addition to the wire that feeds the rest of the harness, make a wire that attaches to the “on” side of the main power switch. This will feed the daisy box that will feed power to all of your accessories.
When you turn the main power switch on, power will be supplied to all other things that require power. Once you have that wired, run a power wire from all your accessories to the daisy box. These will be from the positive side of the fan, fuel pump, and the positive terminal from the wing slider. You will do the same thing to a different daisy box for all of the grounds. All of your grounds will go to one common ground. This bolt can be bolted to the frame anywhere on the car, such as the motor plate. This ground will have a wire feeding the daisy box as well as a ground wire that goes to the engine and the negative post of the battery. From the battery positive side, there will be a wire that comes off the terminal that goes to the relay. This relay feeds the starter, so when you hit the starter button, it will crank over. To wire the starter button, there will be two wires that come out of the harness that goes to the starter button. I think it is different on the Suzuki’s, but this is how it works on the Yamahas.
Check your wiring diagrams to make sure you are wiring everything out of your harness correctly. At this point, you should have everything wired in your car except your wing slider. Just remember to always take your time and plan out your wiring path and where you want everything to be in order to make the dash look as clean as possible. It will take some time but always think everything out. Wiring your wing slider is a little bit different than any of the other switches because rather than a single throw switch like you have for all of your other accessories, you will have a double-throw switch for the wing slider. It will have six terminals on the back of the switch and is a little different from the wire.