[synnamdammit]

Neither does **** on a nun but,,, . My bike will turn the starter with the ecu removed from the bike and VOLTS very low but AMPS must be close to 40 or it will not move correctly , if voltage gets low enough, the relays, which require tiny amounts of amps but at least 9 VOLTS won't click and put juice to the starter. The ecu is programmed not to run the fuel pump if the VOLTAGE is below 9.5 VOLTS at key turn. Some batteries are made of 6 cells at 2 VOLTS and a shovel full of AMPS per cell. Some batteries are 4 cells at 3 VOLTS per cell and a shovel full of amps. So ,,, if 1 cell ain't contributin, it CAN stop the fun. Still not sayin it applies to all bikes, it's just a possibility. I hope this helps.

 

[Bozo]

Whatever system you're describing sounds backwards from what normally occurs with EFI. Anyway, the ECU doesn't suffer the voltage drop from the starter when the key is first turned on so the Rebel's battery doesn't need high amperage to make up for it. It has a wide voltage range. Headlight is usually off automatically so there's everything that needed to get bike started except maybe a good, downhill slope.

Allowing lower voltage/higher amps to supply a high drain is totally backwards. We advanced from 6V to keep things efficient. Lower voltage requires higher amps for the same output and that generates more waste heat and creates other problems. The Rebel won't crank with such a low voltage. Normally, the solenoid clicking saves the system from further voltage drop (and damage) if you continue to hold the button in. The starter motor would need to be wound or geared differently, the whole circuit heavied up to handle the increased amps and probably a huge battery. What bike are you referring to and is the starter original? Sounds like something Moto-Guzzi would do.

 

[Bozo]

Some batteries are 4 cells at 3 VOLTS per cell...

Are you referring to LiFePO4? I have one in my '17 Triumph. At 3V per cell (12 volts), it would only have 9% charge left. I think 13.5V is about where I expect it to be after being charged by the bike. I have to check and lower it to about 70% SoC for winter storage to get the most life ouf of it. Keeping it between 13V and 13.2V is best.

 

[synnamdammit]

OK you are right , I am wrong, and can we please get back to OP's problem? maybe open another thread on the mysteries of batteries and electricity?

 

[jdock]

WOW, do you both have to be right and have the last word??
Its like listening to politicians!

 

[borseth2wings]

So Fikrik, did you find out what the problem was or did you just decide to ignore us bickering guys 😁😁

 

[borseth2wings]

I guess we'll never know. 🙂

 

[borseth2wings]

Over 2 months and the OP never came back to let us know what he found. 🤔🤔🤔