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2005 CRF450R Kill Switch

Ah, ha, #Justin Batty found the problem on my dirt bike. It was a Kill Switch.  I want to thank Justin for finding the problem without costing me 2 months allowance (not enough).  I thought it was going to be a lot worse so, yes, I’m really happy.

There is a lot of discussion on kill switches and yes, it appears to actually be a Federal Law.  This was from a guy named #BigLou (who’s going to question a guy named BigLou?)

First, a little theory of operation for the kill switch cicruit: You have two wires connected to the kill switch. One comes from the coil, the other goes to a ground somewhere on the frame. The switch is “normally open”, meaning those two wires don’t get connected until you push the switch, which grounds the coil and shorts the spark out, killing the engine. If there is a break in either of the wires or any of their connections, including their connections at the kill switch or faulty contacts in the switch, or even a corroded contact anywhere along the path of either of the wires, you can’t complete the circuit to make the engine stop.

Follow the wires to their connections and see if they are pulled apart, or if the wires are damaged/broken anywhere along their path. Try reading the switch through the wires at the connection using a multimeter if you have one. Sometimes older electrical parts will get a corrosion on them even if the connections still look ok. Try unplugging the connections (probaby under the gas tank) and re-plugging them back in. You can try spraying contact cleaner or even WD-40 into the kill switch if it’s not totally sealed. That will knock off any incidental corrosion. If all of that doesn’t work, a new switch is about $14-15. If you’re real adventurous, you can try grounding the engine side of one of the wires at a time to a bare spot of metal on the frame to see if that kills the engine (you may have to use a jumper since these connections are insulated. Careful though, you don’t want to touch the bare jumper wire with your hand. You’ll know if you do it wrong, lol!

Thanks BigLou for you input and again, a Bigger Thanks to Justin!

1 thought on “2005 CRF450R Kill Switch

  1. Thanks BigLou, I mean "Big Justin"; you're the man and thank you for your service as a First Responder; Fire Department.

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