Basically, it's okay to use a car battery to jump a bike, or any 12V battery, as long as it can sustain the power requirements of the bike (i.e... a 12V flashlight battery might not work, but a 12V boat battery probably would).
What you DON'T want to do is have the car running when you try to jump the bike. The car's alternator can fry certain components, including, but not limited to, the wiring harness.
Follow these directions, and be careful:
- Turn the car off.
- Turn the car off.
- Turn the Ninja 250's red kill switch and ignition switch (key) to the off positions.
- Do not smoke; batteries sometimes give off explosive hydrogen gas. Don't light incense, either.
- Take the seat off your Ninja 250 and study the battery. Locate the positive terminal.
- Open the hood of your car and study the battery. Locate the positive and negative terminals. Positive terminals are usually marked with a + or some kind of red paint. And if you didn't know that, get somebody to help you do this before you blow yourself to smithereens.
- You shouldn't have to, but you might need to put the car's key in the "accessory" position. Do not start the car.
- Do not start the car. Period. For any reason.
- Using the red clips of your jumper cables, connect the positive terminal of the car's battery to the positive terminal of the bike's battery.
- Connect one black clip of your jumper cables to the car's negative battery terminal. DON'T let the red and black jumper clips touch each other.
- Connect the other black clip of your jumper cables to the brake pedal on your Ninja 250. If you've done everything right, there should be a little spark when this happens, as you're completing a circuit.
- Turn the Ninja 250's red kill switch and ignition switch (key) to their respective on positions.
- Thumb the starter (vroom, vroom!).
- Disconnect the jumper cables in the exact same order you connected them.
- Put the cables back in the trunk.