My magic battery

So I've had this bike for about three years. The battery was never the zestiest but was doing alright. I didn't take good care of it over the winters and this spring when the temperature was below 60C I had to bump start it because the engine would turn over slowly and weakly till it would stop turning over at all. Once the bike had been running for 10 minutes it would fire up without issue so I just sort of ignored it and parked on hills. Well earlier today I was going to buy a new battery when I decided to check the fluid levels (I should have done this a long time ago I know).

Nothing. No fluid...... I'm talking holding the battery completely upside down with all of the caps off and not a drop comes out.

How the hell was this battery working at all?? It boggles my mind. Anyways I filled the battery with distilled water on the recommendation of an auto shop and the manual. I haven't had the chance to start the bike cold but when it is warm it still fires up in less than a second. I would like another opinion on this though. I feel like I should have filled it with fresh battery acid because there should be acid in there right? I know you should top off with distilled water but given the extreme circumstances I feel that it should have been acid.

 

It's probably an absorbed glass mat battery. Some brands still use the same cases as flooded batteries.

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