Can you push start a turbo busa with a dead battery?

megawatt

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Ok, I have a RCC turbo kit still running in a FMU with the external fuel pump that comes with the kit. I have had my turbo busa since 2011 with no issues. I always put my bike on a battery tender and never had battery problems. So today I was trying to think of when I replaced my battery last, (battery works just fine)? Ok, a lot of chatter but here is my question for you.

If the battery dies when I am out riding. Will I be able to push start the turbo busa? I ask because when I turn the key on, I can hear the fuel pump start and pressurize the system prior to ignition. But if the battery is dead and you try to push start you obviously don’t get the priming action from the fuel pump.

I have turned off my bike while rolling at 30 mph and popped the clutch and the bike acts like any other bike and starts up. But the fuel rails and lines are still pumped up so I don’t think that is a reproduction as if I stop for lunch somewhere and 40 minutes later try to start the bike on a dead battery. So, would I be stranded or could I push start the bike and get home?

Mr Brown

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Not if there isn't enough juice to pop the injectors. Can you take a small jump pack with you?

Bailey9r

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Your saying "a dead battery" then no as there is more than fuel pump that needs to be powered BUT if you mean low battery too low just to turn over then I think it would start like you do when testing it

mabupa

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I’m no expert, specially when it comes to turbo bikes, but hayabusas act really crazy when battery is weak.

Mr Brown

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Turbo bikes are typically lower compression, so that's a plus. However, I know from experience that just because the fuel pump runs doesn't mean there's enough juice to fire the injectors.

Rocketmn

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I think there has to be 12v. at the injectors when the battery is under a load (starter). If not, I believe the injectors won't open. **I could be wrong.**

Kiwi Rider

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Ok, I have a RCC turbo kit still running in a FMU with the external fuel pump that comes with the kit. I have had my turbo busa since 2011 with no issues. I always put my bike on a battery tender and never had battery problems. So today I was trying to think of when I replaced my battery last, (battery works just fine)? Ok, a lot of chatter but here is my question for you.

If the battery dies when I am out riding. Will I be able to push start the turbo busa? I ask because when I turn the key on, I can hear the fuel pump start and pressurize the system prior to ignition. But if the battery is dead and you try to push start you obviously don’t get the priming action from the fuel pump.

I have turned off my bike while rolling at 30 mph and popped the clutch and the bike acts like any other bike and starts up. But the fuel rails and lines are still pumped up so I don’t think that is a reproduction as if I stop for lunch somewhere and 40 minutes later try to start the bike on a dead battery. So, would I be stranded or could I push start the bike and get home?
If the battery voltage is below 10 volts and the cells 'storage capacity' is at a low also, (stuffed battery in technical terms lol) and you 'push start ' the bike you have to realise that the bike's electrical charging system is generating volts and current when the motor is spinning due to being in gear and being pushed.
This will bring the charging voltage up to maybe 12.5v (depending on the RPM of the crankshaft) and this will supply the necessary 'juice' to the ECU, the coils and (hopefully) the fuel pump.
I say 'hopefully' because the fuel pump requires a reasonable current supply (amps) to make it work.
If the battery is really flat (say, 5 volts) the charging system may not be able to supply adequate voltage and current (amps) to the fuel pump,
as the battery storage capacity is 'soaking' up the volts and current being generated by the stator, and unable to supply the voltage OVER the threshold the ECU, coils, and fuel pump demandd.
You see . . . it;s all about supply and demand.
Hope that explains it in a way you can understand it.

Sandow

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Ok, I have a RCC turbo kit still running in a FMU with the external fuel pump that comes with the kit. I have had my turbo busa since 2011 with no issues. I always put my bike on a battery tender and never had battery problems. So today I was trying to think of when I replaced my battery last, (battery works just fine)? Ok, a lot of chatter but here is my question for you.

If the battery dies when I am out riding. Will I be able to push start the turbo busa? I ask because when I turn the key on, I can hear the fuel pump start and pressurize the system prior to ignition. But if the battery is dead and you try to push start you obviously don’t get the priming action from the fuel pump.

I have turned off my bike while rolling at 30 mph and popped the clutch and the bike acts like any other bike and starts up. But the fuel rails and lines are still pumped up so I don’t think that is a reproduction as if I stop for lunch somewhere and 40 minutes later try to start the bike on a dead battery. So, would I be stranded or could I push start the bike and get home?

I dont have a turbo but I tried in the past to push the bike when the battery was empty. I couldnt do it although im a big guy. I got a batterypack starter from amazon for 30 bucks and have it always with me in the bike. works well and is very easy!Definitely worth it to have!

VIPER

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answer is no. you can not.
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