Low Voltage
Thread Starter
|
Road Captain
Joined: Jan 2014
Posts: 641
Likes: 48
From: Brisbane
Low Voltage
Some of you may have seen the thread I hijacked in the tuning section about backfiring when starting. I have resolved the backfiring issue with help from a very helpful fellow member, and then complained of slow cranking after I modified the map. I think that was just a coincidence, and actually had nothing to do with the changes I made. I mentioned how I had recently had my battery load tested only a few weeks ago and it was fine, but now the first crank is very slow. I decided to check the connections before I went spending hundreds on a new battery and found the ground cable on the battery slightly loose. I tightened it with no change to the slow cranking. So I thought while the seats off I'd put the multimeter on it and see what it does. With the bike just sitting there it read a constant 12.78V. 12.28V with the ignition, headlight etc on. Then on the first crank it dropped down to 7.25V. I shut the bike off and retried and got around 10.5V (The bike ran for about 10 seconds between starts)
So now to my actual question, can someone tell me if there is a certain voltage where you decide the battery is no good???
Sorry to make it so drawn out, just trying to provide info!!
Thanks in advance, Matt.
So now to my actual question, can someone tell me if there is a certain voltage where you decide the battery is no good???
Sorry to make it so drawn out, just trying to provide info!!
Thanks in advance, Matt.
Road Warrior
Joined: Sep 2014
Posts: 1,870
Likes: 1,324
From: DeLand, Florida
Dropping to 7.5v when cranking is not good. You say you tightened connections. Try removing and actually cleaning them bright and shiny then recheck voltage while starting. But it really sounds like a new battery is in your future.
Thread Starter
|
Road Captain
Joined: Jan 2014
Posts: 641
Likes: 48
From: Brisbane
Ok, thanks cobra. The connections were clean, no sign of corrosion at all, but not 'shiny' clean! I'll give them a clean up and try again, but I think you're right, I think I'll be off to get a new battery tomorrow! Thanks mate!!
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,897
From: Bedford UK
Also check the other end of each main battery cable. They may be clean at the battery, but if they are dirty/rusty at the other ends the poor little electrons will get all confused when you ask them to turn the engine over! Often apparently electrical problems are actually mechanical, in other words simple stuff.
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,321
Likes: 56,883
From: Michigan 15 Minutes East Of Hell
As suggested, be sure that all of your connections are clean and tight, as poor connections will give false readings. It sure sounds as though your battery is "kaput"
Thread
Thread Starter
Forum
Replies
Last Post
