I heard somewhere it was bad to bump start a fuel injected bike. If this is true how come?

Thanks

I'm not 100% sure (others can pipe in) but I can't see a problem.

I truthfully don't know for sure, but I immagine that if you have a starter go out, it is ok to bump start, but if you have a battery go completely dead, it's not ok. I say this because, if the battery is COMPLETELY dead, the fuel pump can't run before starting the engine. The computer also can't wake up and figure out what's going on until the engine is turning and creating power to recharge the battery. I would immagine though... it would be ok to bump start an FI bike if the battery at least had enough juice to power the computer and run the fuel pump. I know this is the case with manual tranny cars. The rally car always used to lose battery charge in the winter (because it had a lawn-mower battery) and as long as it wasnt COMPLETELY dead, I could roll it down the driveway and get it started before I hit the street... but if it was COMPLETELY dead... well... it's a good thing it was only a 2800# car, because I had to push it down the road and hop in, put it in gear, drop the clutch, and repeat a couple times to get it going.

What about jump starting if battery is completely dead (efi flavor). I have the small size jumper cables stored under the seat, but has been no need to use them on the XX so rar. I know they worked on the cbr1000f, don't ask how i know this (and no, it wasn't honda's fault!).

That should work, but as a general rule, especially if what you are jumping with is computer controlled, you want to give the dead battery a bit of a charge with the running power donor, then disconnect the cables and try and start the one with the dead battery. This is because as a vehicle is started, sometimes the voltage can spike and may fry the computer of the power donor vehicle... I have seen this twice. If there is no choice (completely shot battery, or no battery connected), you can start the cranking with the cables connected, but disconnect them right as the engine starts to fire... specifically before the engine flares at startup.

"Go fo IT"...that's my lousy Rocky impersanation.

I say this only because I had to push start my 600RR the other weekend. If you have to do it, what's the harm if you only have to do it once or twice in the bike's lifetime??

Come on guys...it's a bike, not a fine piece of china!!!

I may be wrong, but if the battery is completely dead, there won't be power to "prime" the FI (the noise you hear when you turn on the key), so it wouldn't bump start anyway. Right?

I agree that the problem is that it might not start. If you have a completely dead battery, there will be no juice to get the ...er...juice up to the cyclinders. At least with a carbed bike, if you can get spark, you get the pattern going and away you go. I find that if I have a completely flat battery, I can't even push start the bike due to lack of initial spark.

:roll: :banghead:


Absolutely not true.

Connect both vehicles, taking care to get a good connection, and preferrably the first time. Then, start the donor vehicle. Wait a minute or two, then attempt to start the one with the dead battery.

Leave them connected for a few minutes if possible, to reduce some of the load on the alternator of the vehicle being jump-started.

I don't know where the voltage spike is supposed to come from after they are both connected, or who told you that, but I've been doing this for a long time, and never seen a computer "fried" from jump starting, unless you connect it backwards or something. :???:

I have never had one of mine fried, but my auto shop teacher in high school told me that. I heard it again from the ASC Master Mechanic that I worked for between classes up until this last Dec when I graduated. They both said they had only had problems with it when jumping old stuff with newer, computer controlled stuff, but I'd rather be safe than sorry.

Bump!



Oh Crap, I saw the header and thought I was in one of those bump threads.

My Bad.