CBR 400RR NC29, Babyblade battery

[Raggers]

i was out riding yesterday when i stopped to have a drink. enjoying the views i was there for about 15 mins. i cant remember if i had the battery running or not but i thought it couldn't do much harm. this was a big fuck up on my behalf because being 18 (the motorbike) years old and being anything that's 18 it didn't want to work.
this is my first time changing a battery on something bigger than a 125cc. i don't have any spare hands. i need to recharge the battery and don't know where to begin.

[Mungel]

Get a trickle charger (Optimate or similar), locate battery (Usually under seat), Attach charger, observing polarity on the battery (+/-), leave to charge for many hours. Job jobbed.

Being that the bike is 18 years old, do you know how old the battery is? It may just need replacing with a new one as they don't last forever.

If the battery is not old, there may be other electrical issues causing it to go flat and you will have to investigate further.

Welcome to the world of automotive electrics, not fun at the best of times.
____________________
Mungel
ZZR600 (dead) - ZX9R (sold) - FZ1S

[Raggers]

cheers for the help, i literally just bought the bike so i don't know when it last got charged. so i will wait until i next have to charge it. the guy i bought it of did say it was new but that could be a lie (not to sure he seemed like he wasn't lying). but it did have some rust and battery shit around the top. but i shall see.