Battery drops to 0 volts when ignition key turned to ON

If it's broken or just needs tweaked

Moderators: Volker_P, tidd650

AndrewCB650
Posts: 32
Joined: Wed Mar 11, 2015 8:18 pm

Battery drops to 0 volts when ignition key turned to ON

Postby AndrewCB650 » Mon Nov 14, 2016 6:48 pm

Hey Guys, I've got a brand new Lithium battery on my 81 cb650 and when I turn the key to ON the battery voltage drops to 0 from 13.5. The battery has been working great and the bike starts everytime, I also replaced my charging system about 2 months ago, along with the battery. I know some will say it's the battery, but i had the battery tested and I put it into another bike(74 suzuki GT380) and it works perfectly. Could there be a short in the ignition system? I've dealt with plenty of bad batteries but i've never seen the voltage drop to 0 just by turning the key.. Any advice? As always, I thank you!

MEHall
Posts: 403
Joined: Mon Nov 15, 2010 8:25 am
Location: Sweden

Re: Battery drops to 0 volts when ignition key turned to ON

Postby MEHall » Tue Nov 15, 2016 11:12 am

Not sure what the problem can be but with a good multimeter you can find out if there is a short somewhere.
If it's a Lithium iron phosphate battery you use i recommend that you change back to the lead acid battery as the charging system is not made to work with anything else. :wink: :roll: That could do the trick but without knowing if there is any problem in the electrical system it's hard to tell. :?





8)
Riding bikes? I ride where ever i want and whenever i want. :wink:

Online manual: http://cosky0.tripod.com/

AndrewCB650
Posts: 32
Joined: Wed Mar 11, 2015 8:18 pm

Re: Battery drops to 0 volts when ignition key turned to ON

Postby AndrewCB650 » Tue Nov 15, 2016 1:22 pm

Thank you for the reply. I did try my old lead battery but got the same results, which makes me think it's a short. I'm confused why a lithium battery doesn't work with these charging systems, it's still a 12v battery but with advantages. I run lithium ion batteries in all my bikes and have never had a problem, most of the bikes are from the 70's-80s. I'm still leaning on a possible short somewhere in the wiring harness, i'm going to start checking my grounds. Thanks!

MEHall
Posts: 403
Joined: Mon Nov 15, 2010 8:25 am
Location: Sweden

Re: Battery drops to 0 volts when ignition key turned to ON

Postby MEHall » Wed Nov 16, 2016 11:34 am

Well that is a bit complicated but a Lithium iron phosphate battery need a more stable charging than an over 30 year old charging system can deliver, so much i know at least.
Myself i had problem with no charging and in the end it was the harness that was faulty. :shock: :roll: :?
What you can use if the ordiary lead acid battery turns a bit weak is a start help with Lithium iron phosphate batteries in it.


Something like this:

https://shop.antigravitybatteries.com/products/micro-starts/xp-1/

I have something similar and it works great if my bike have'nt ben run for a couple of weeks or so.
Especially after the winter hibernation. :wink:





8)
Riding bikes? I ride where ever i want and whenever i want. :wink:

Online manual: http://cosky0.tripod.com/

AndrewCB650
Posts: 32
Joined: Wed Mar 11, 2015 8:18 pm

Re: Battery drops to 0 volts when ignition key turned to ON

Postby AndrewCB650 » Thu Nov 17, 2016 9:19 am

Thanks man. I've decided to replace the wiring harness, i've wanted to for a while now. Also, the battery was under warranty, and "bikemaster" was cool about sending a replacement for free, so I just went ahead and did that. I think it's a combination of a shorted wire and weak battery, we'll see how it does after a new harness. Cheers.


Return to “Technical Discussion”

Who is online

Users browsing this forum: Google [Bot] and 43 guests