Roadking draining battery
Road Captain
Joined: Sep 2009
Posts: 526
Likes: 99
From: Merrimack NH
Have it load tested. I had the same problem recently. Ended up being a bad cell in the battery. It would take a charge and start the bike right after disconnecting the battery tender. Let it sit overnight without tender and it would be dead.
Road Master
Joined: Jul 2010
Posts: 1,045
Likes: 102
From: Waukesha, WI
If you won't be riding it for more than a few days, keep it plugged in. As for now, take the battery in somewhere and have it load tested. If the battery is more than 4-5 years old it's probably starting to go south, a load test will give the current state of health. IIRC OE bagger batteries are rated at 410cca. You may have 12.65v, however only be down to 200cca. If the battery is toast, get a replacement designed for a motorcycle. I've seen it numerous times where someone comes in with a two year old dead battery, only to find its a lawn tractor or golf cart battery (multiple application design). Motorcycles, especially Harleys, shake the living hell out of the battery and are physically tough on them. Also stick with AGM as opposed to the cheaper lead-acid type.
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
In addition to all the good advice above, consider a few simple house-keeping tasks, such as cleaning and tightening both ends of both main battery cables. Use a little dialectric grease on them before reassembly. A dry, corroded or slack fastener on any one of them can increase resistance and hence reduce battery performance when starting. Do the same with other major electrical connectors/grounds associated with the starting circuit.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,527
Likes: 6,406
From: Honah Lee
Replace the battery. Or put a DC meter set on amps between positive cable and battery. With key off, it should be less the 150 miliamps for speedometer, ecm and alarm draw.
If it's more, you are going to half to pull fuses to find problem.
Two weeks on a sulfated worn out battery is good however.
Usually if it last that long, it's the battery
If it's more, you are going to half to pull fuses to find problem.
Two weeks on a sulfated worn out battery is good however.
Usually if it last that long, it's the battery
Seasoned HDF Member
Joined: Feb 2007
Posts: 6,081
Likes: 1,127
From:
After reading it a few times it would seem that you have a bike that will not start after a few weeks of no use.
Would a few weeks be 2 weeks, 8 weeks, 16 weeks?
Reason: A regular lead acid/agm (wet battery) will have a loss of charge over time. A small demand like an alarm could cause a no start situation after several weeks (6 weeks).
You report no security system but then we learn that you have keyless start...guessing you have a key fob..is it factory?
Would it be possible that you do have a security system since it requires key fob proximity to start.
A keyless system could cause bike to not go to sleep and it would maintain a slight demand on system.
OR is it possible that your bike does have a siren and the rechargeable battery for siren has become compromised and is causing a parasitic drain situation.
You report that battery was tested and takes a charge (takes a charge from what? from bike or wall charger?)...How old is the battery? How was it tested? was that a load test? a meter at battery? what test was performed?
From a distance and based on information available it would seem like there might be a parasitic drain but you really need to confirm battery condition, motorcycle charging condition and then reason for drain.
Here is a link for a parasitic drain test.
Road Master
Joined: Apr 2012
Posts: 1,229
Likes: 240
From: On 2 rails...
I leave my bikes plugged in year round, had a road king with an older style tender that had a slide switch on back of it, left was 1A, Center was off (power light stays green in this position) and right side was 2A. The charger inadvertently got switched to off position when my wife moved it to get into roll chest it was sitting on. She always checks for green light when I am away for work. It was green but because charger was off the electronics wiped out battery. Lesson learned battery was 5 years old, I simply replaced it and got a battery tender brand that has no switches.
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Seasoned HDF Member
Joined: Jan 2007
Posts: 20,616
Likes: 4,440
From: anacoco, la
You report no security system but then we learn that you have keyless start...guessing you have a key fob..is it factory?
Would it be possible that you do have a security system since it requires key fob proximity to start.
A keyless system could cause bike to not go to sleep and it would maintain a slight demand on system.
Would it be possible that you do have a security system since it requires key fob proximity to start.
A keyless system could cause bike to not go to sleep and it would maintain a slight demand on system.
Seasoned HDF Member
Joined: Feb 2007
Posts: 6,081
Likes: 1,127
From:
Good to know about year of availability for proximity sensor as i did not know that information.
Original Poster in post #5 states they have keyless start.
What is keyless start ? aftermarket? remote control?
Alarms, sirens, security stuff is sometimes the cause of a battery drain.
The rechargeable battery on a siren had me guessing on a car once.
Unfortunately, confirmation can not be made until a parasitic drain test is performed.
Hopefully the poster will return.
Original Poster in post #5 states they have keyless start.
What is keyless start ? aftermarket? remote control?
Alarms, sirens, security stuff is sometimes the cause of a battery drain.
The rechargeable battery on a siren had me guessing on a car once.
Unfortunately, confirmation can not be made until a parasitic drain test is performed.
Hopefully the poster will return.
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