starting/Battery problem..

Okay so my 82 xj750 been showing "BATT" on the front LCD for a while now. I think it needs a new battery?

If so, can anyone guide me through this? I have the Haynes manual but it doesn't give an actual guide on HOW to remove the battery and what not. I'm a total newb so yeah plz help. Thank you

 

your battery very well could be fine. there's a sensor that goes bad, or is disconnected, or is missing that causes the BATT light to come on.

to get at your battery, remove the right side cover (if you're lucky enough to still have one). the cover just pops off. but be careful not to crack or break any of the tabs/prongs that hold it in place - they're a hard item to come by.

under the side cover, you're battery is held in place by a large rubber band thingy. unhook one end and you can disconnect the cables and it's out.

since you've got the cover off, you might as well grab a volt meter and check out your charging system.

if memory serves, your battery should read around 12.5 volts with everything off. you should see a drop while it's turning over (down to 11.5 volts, i think). and at idle your battery should be back at 12.5V. Rev it up over 2000 rpms and you should be between 14.2 and 14.8 volts.

someone else, please chime in if my voltage numbers are wrong - i think they're at least close to right.

disclaimer - i'm basing this off my '81 XJ750 Seca. I'm assuming your bike is the same or very similar - but individual results may vary.

what are your starting problems?

 

Rick just posted the charging numbers in another thread, and you are right on.

 

well before I would usually just give a bit of throttle to start the bike up or rather to help start the bike up. Now I give it throttle + push start button but bike doesn't come on at all.

 

you shouldn't need to give it any throttle to start. just some choke.

does anything come on? or is it just the starter doesn't turn over? or does it just crank and crank and never starts up?

 

The battery sensor looks for electrolite in the battery to see voltage. When it gets below the sensor the light comes on.
Have you checked the battery electrolite level? Could be low level or the voltage is low.

 

do you get lights when you turn the key? typically if you dont get anything, it's the fusebox on those. check/replace it. get a volt meter and check your battery voltage and voltage before and after the fuses.