Jump starting bike wont run without cables

 

Sorry not thinking and probably did that wrong. I have two issues hopefully I can fig out.
The bike is a 1988 sportster
Hdxl883, stage 1 cam, air cleaner.
Problem 1: battery died and thats ok ill get a new one. But while fixing problem 2, I noticed that when jumping bike, off of 2 cars to get enough juice, that when I took bike off of the cables it died.
My question is doesn't the bike make power and once runnig shouldn't it continue to run battery or not

 

The bike will not run without a good battery. Older kick-start bikes with magnetos didn't need a battery, but newer ones do. Your car won't run without a good battery either.

 

was the bike battery disconnected when you tried to jump it??? if no, the battery probably has a short in it...and that is why it was so hard to jump = replace battery...also the bike should run without the battery...although not very well and it may not idle...if it dies as soon as you take off the jumpers (battery disconnected from bike), like someone turned the run switch off, then you have a charging problem,,,,either way you MAY have a charging problem...get the battery tested, don't just replace it (unless its old and you think its time for it to die soon)...to test the charging system you are kind of need a good battery, so that is a good place to start...

 

Thank you. Yes battery is in, is old, bike idles great when running. Having carb problems (bike stalls when applying throttle), and dont really want to burn a new battery figuring it out, so I am jumping it( takes two cars to start it?) Just happened to notice when cables shook off bike died. I am super newbie and know nothing so could somebody explain what consist within the charging system so I might take a look. Thanks for all the help

 

I hate to tell you, but if your bike's charging system wasn't already dead, it likely is now.
The bikes' little 20 amp charging system is designed to handle and work with the bikes SMALL battery. Unless your using a car battery that's disconnected from the vehicle and the car battery is at a 100% full charge, leaving jumper cables connected for more than a second or two after the bike's motor starts will place a bigger load on the charging system than it was designed to handle and the regulator will be toast.

First you need to start by installing a known good and fully charged battery in the bike.
As soon as you start the bike, you need to check the charging system for proper operation. If's it's not charging, fix it, before you kill another battery.

 

Thanks im guess

 

Guessing there is a post here somewhere diagraming the charging sys. Also the battery unused over4 years already bad just stumbled onto chargeing prob finishing carb rebuild left unfinished by somebody thanx to all 4 all valuable info and thanx to hdforum