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Can you bump start a fuel injected harley with a dead battery?

41K views 14 replies 13 participants last post by  scootertramp 
#1 ·
If your battery is dead will it bump start or does the fuel pump and computor need juice first
 
#2 ·
I am pretty certain that the system needs power first because all the sensors have to "tell" the ECM when to fire the plugs.

I have witnessed about six large fellows attempt push starting a bike that was FI and nothing happened. They were done after the 10th try.

A great test would be to place a dead battery in a bike and try to coast start it down a good slope.

Has anyone else tried this?
 
#4 ·
That is what I was thinking too.

I miss the days of kickers. Man, many times have I had a bike's battery go south with no warning and the kick start save the day. But those were bikes that were carbs, coils, points, and that's about it. There were not any ECMs telling anything. It was a simple and sometimes frustrating system that had this one life saving feature.
 
#11 ·
That's the main point. No fuel pump at the initial point will probably prevent it from starting. You need to have a signal that the pressure is up before the machine will start. I'll go a bit farther to say that it's probably not a good idea to do anything wih a bike that has a TOTALLY dead battery. Good solid voltage is the best for your system.

My 2 cents.
 
#9 ·
Mine was dead enough to not crank it to start. Bump start, kicked right over, check engine lamp and charging lamp came on. Took to dealer and they put in a new regulator under warranty. Don't know why this would have happened though.

Chris
 
#14 ·
Took to dealer and they put in a new regulator under warranty. Don't know why this would have happened though.
Chris
If the regulator fails, it won't charge the battery, so the battery will die.
 
#10 ·
You cant "bump" start a FI system if the battery is TOTALLY dead..0 volts as would happen if you left something on or had a short.But you can bump start a very low battery.You just have to have a little in the battery to power the ECM and pump as mentioned.
And just a reminder to guys with older tourers..check to see if your regulator plug has been moved to the updated position.This mainly applies to the early
TC88's that had the plug mounted low and it filled with water that wicked into the stator and shorted it out giving you a intermitent no charge untill it finally totally burns out.Newer tourers were all updated from the factory.

Just my 2 cents worth-2$en#e-
Posttal AKA Ralph
 
#15 ·
That's why I always carry a small set of jumper cables in my coat. I could carry them in my saddlebag but none of my other bikkes have saddle bags. Just small tool pouches. And sure as sh*t I'd need em and they'd be on the land yacht! Man those things have saved many of my friends over the years. Just some 12 guage wire with alligator clips.
 
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