Well.. it could be a couple of things... Your Rebel has a charging system so it should be charging the battery.. Check all the simple things first..
How much do you ride it.. and are you riding it to where it will charge the battery.. Meaning to get out in the high gears..

I know you have been changing the battery, but check the that thee is good contact at the terminals.. A friend had this happen with her car.. it turned out all it was, was one of her terminals was not making good contact.. I cleaned them good, and cleaned the battery posts and made sure it was tight.. and that fixed it.. her battery charges now... I have bikes come in the shop and when I go to disconnect the battery to do some work.. I can do it with out any tools.. if it can be wiggled of it is not right..

Have you added anything.. Like a sound system, gps and large screen t.v. for your passenger... okay, I have seen a large screen on a bike yet, but I have seen them with so many extras that it drains the battery... Had one guy who added lights, and 4 different power plugs, 1. Gps, 2, Ipod, 3. phone and 4. Radar Detector.. well, no wonder his battery was draining..

Okay if it is none of those we will go from here..

 

If you have a volt meter .
put it in DC volt setting .
check the voltage of the batt engine off should be 12.0 to 12.8 volt.
start engine and check Batt voltage
and it should be between 13 volt - 14 volt wiht engine at high idle.

 

Greetings gnaz1956,

Could you post the steps that you did when you replaced the first Battery.

Steps when you replaced each additional Battery.

 

Sounds like alot of short low speed trips. Not enough RPMs for a long time to keep the batteries charged.
The rebel 250 at idle will not charge the battery.

 

The first question is
What kind of electrical stuff do you have on the bike?

A set of Halogen Driving lamps will overtax the charging system greatly and draw the battery down with each ride.

 

Make sure you check the cables, both ends the bike end and the battery ends

 

Oh no.. is it draining the computer battery too...

Okay just kidding.. wanted to know where we were at with this....

 

When I bought mine I duck walked to get started several times. I wanted a new battery, but no money. After riding the crap out of it 2 days, hard throttle like i stole it.:lol2: Now no issues with the battery. Saved myself some money.