Buy a new bike - behave like a rookie...

[DanielB]

Hi there,

Was not hoping to start such a post anytime soon, but I've had one "not so smart" day on my calendar last week and now need some help.

First things first: fresh owner of a 2004 FZ6S that I recently bought, in a state that needed some fixing. Since I had some time on Saturday, I thought of at least hearing the motor running, as had not heard it running on purchase (it was a bargain, so I just went ahead with it. The battery was dead, as far as I could tell, so I through I'd jump start it from my car. I do have other motorbikes and did this before, but this time, somehow I left the car motor running and didn#t think twice about it. Engine turned, fuel pump worked, but no joy and at some point everything on the bike went dead... already checked the fuses under tank fuses and the ones in the back, (Forgot the gyro one, but I guess that's not the culprit), they're not blown. But now I cannot anything to light up, there's literally no sign of life on this bike. So, aside from being the idiot I am, what else can I check aside from expecting a fried ECU? Is a fried ECU going to kill all power on the bike? Fyi, it's my first injection-type motorbike

Thanks in advance, awaiting the rotten tomatoes

 

[Gary in NJ]

Sorry to hear about your problems. Using a car battery to start a motorcycle is always a controversial subject on motorcycle forums. A typical car battery can deliver 7,000 to 9,000 watts (V x A = W), whereas the battery in your FZ6 can deliver around 200 to 300 watts during a start. A car uses 0 gauge wiring to handle the current that the battery has the potential to deliver. Motorcycles use 12 gauge wire to handle the current that the battery can deliver and that the starter can use. To use a car battery safely in this application the starter should only be engaged for seconds at a time, allowing for almost a minute between attempts for the starter and wires to cool.

The fuses on your bike use heat and time to trip (open) - not necessarily current (the fuses are sized assuming that you are using a properly rated battery). When you engaged the starter on your bike (requesting a high current into the system), the car battery delivered more current than the wires could safely deliver. This caused a rapid temperature rise in the starter and wires, and it was probably rapid enough that the fuse could not react in time. As a result, one of the wires in your harness may have became the fuse. Or perhaps a relay became the fuse...or as you suspect (but less likely), the ECU.

You are going to have to trouble shoot this problem with a multi-meter, starting at the source (battery connections) and moving down-stream from there. Check for continuity between the battery positive and

Main switch
Rectifier/regulator
Main Fuse
Fuel Injection Fuse
Backup Fuse
Starter relay
Starter motor
Starting circuit cut-off relay

These represent the first connections for power and are the most likely to see damage. Also, be sure to inspect the associated grounds. In addition to continuity, check the connectors for burned pins and the harness itself for signs of burning (brittleness).

 

[Motogiro]

Welcome to out great forum!
You can use any 12 vdc nominal voltage source to jump start or run your bike. The problem is not a higher voltage capability for the source. The problem is the higher charging current a car alternator is capable of when attached to your bike. Your bike can easily handle the voltage of the car. They are both 12 volt DC systems. You could hook 100 parallel attached car batteries to your bike and the the bike has no problem and sees it as a single 12 vdc supply.
Your motorcycle uses a shunt regulator to regulate charge to your battery/electrical system, The stator produces alternating power that the shunt regulator is designed to rectify to DC and load down so that once the desired voltage is attained, the regulator basically converts power not needed to heat that is dissipated through it's heat sink. This function is provided at a specific voltage threshold and the shunt is more a current regulator than it is voltage regulator.
The automobile alternator is basically considered a series regulated system which basically means an open circuit is provide so that the field winding on the alternator becomes inactive reducing the magnetic field required to produce output power.
Here is where the problem with jumping the bike from a car becomes a problem: The car alternator produces far more current than the motorcycle shunt regulator can dissipate into heat and the shunt fails and can not function as a regulator any more. For this reason you never jump start or use a car to the bike unless the car engine is not operating. You can safely use the car battery as a jumper or source voltage to the bike but the engine must not be running because the car alternator produces more current (amperage) than the bike shunt regulator can handle.
From what you've described the regulator/rectifier is likely damaged. The first thing that might happened is the main 30 amp fuse blew. If the shunt in the regulator shorted the positive to ground the fuse would blow.
I recommend disconnecting the regulator/rectifier plug. Pull the main 30 amp fuse and confirm it is not blown. If blown, replace. Then you can attach a 12 vdc source. Car with the engine off?! and see if the bike becomes active.

Question: What's the gyro one?

 

[Gary in NJ]

Question: What's the gyro one?

My guess was the tip-over sensor.

 

[Motogiro]

Any news?