Battery charging question

borat

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I’ve bought the proper bmw canbus charger and when I first plugged it in to din socket it showed about 25% charge. I thought maybe it was because I’d been messing with settings so didn’t worry and it charged to 100% fine. Been out today for a decent ride and when I got back I plugged in the charger immediately and it showed it starting from 25%?! Surely after a ride it should still be close to 100? Anyone else got the charger and can you confirm if yours does or doesn’t behave this way pls?

Thanks
 
I have the charger also - this is normal - it is 'some cycle' the charger runs through. Sorry cannot be more technical!
 
I have the charger also - this is normal - it is 'some cycle' the charger runs through. Sorry cannot be more technical!
Thanks. Does that mean that the battery is not actually at 25% when you plug it in?
 
Same with mine. 100% normal

I do have a question though. When connected to the canbus my charger never goes to sleep. Keeps charging.

I installed an SAE lead directly to the battery and when connected that way it will go to sleep and maintain the battery.
 
Same with mine. 100% normal

I do have a question though. When connected to the canbus my charger never goes to sleep. Keeps charging.

I installed an SAE lead directly to the battery and when connected that way it will go to sleep and maintain the battery.

you have electronics in the charger, the bike and inside the battery. Plenty of scope for electrons getting confused.

using a direct to battery connection removes the most likely cause of confusion
 
you have electronics in the charger, the bike and inside the battery. Plenty of scope for electrons getting confused.

using a direct to battery connection removes the most likely cause of confusion
You would think BMW to BMW connection wouldn’t get confused.

Will stick to the direct connection.
 
As above, its 100% normal, if you have the patience watch the display for 5 mins, it will soon show the actual battery capacity when its gone through all its cycles.
 
Same with mine. 100% normal

I do have a question though. When connected to the canbus my charger never goes to sleep. Keeps charging.

I installed an SAE lead directly to the battery and when connected that way it will go to sleep and maintain the battery.
Just leave it connected and it will eventually go to sleep, may even be after 24hrs, just trust it. It is a battery maintainer not just a simple charger. Mine usually goes to sleep and dims the display after leaving it on overnight.
 
Why are people needing to put a charger on all the time? I have the Lith battery and have never put a charger on it and it's been perfect all summer. Bike sits for a couple of weeks sometimes. In the past 30 years of regular Yuasa AGM batteries I've never needed a charge, even after4 5 months winter storage in a heated basement battery never drops below 13 volts. What's the thinking behind keeping a charger on whenever the bike isn't being used. ?
 
Maybe it’s those bikes with alarms and/or trackers. They tend to drain a battery.
 
Maybe it’s those bikes with alarms and/or trackers. They tend to drain a battery.
I don’t think so.

Mine has a tracker, but I only have problems in the winter, when I use the heated grips. I should also note that my commute is only a few miles, so it perhaps loses a little every day in the winter, but keeps up in the summer.

Of course, I’m much more likely to go for a ride in the evening or at the weekend if it’s not dark, cold, wet and miserable, so the driving pattern changes with the seasons too.

It’s on a trickle charger at the moment as I have a broken ankle and can’t ride for 4 weeks.
 
My BMW plus charger always starts off from 0% when I connect after a ride and it goes up to 100% fairly quickly.
My main gripe is that it somehow switches the satnav on, even though the bike is switched off, the satnav then says power lost and switches off but sometimes it just stays on and goes flat. It can come on hours later so I don’t notice it.
It doesn’t happen when not connected to the charger.
 
My 1250 always needed a trickle charge, I put it down to the tracker drain. Then it failed to hit (re)start on me a few times, leaving me stranded despite a presumably full battery.

I fitted a Hybrid Lithium/AGM battery and it never needs a recharge. I can now leave it for weeks and it still bursts into life.


Sent from my iPhone using Tapatalk
 
That should be hot (re)start, not hit. …..Bloody autocorrect again.


Sent from my iPhone using Tapatalk
 
Trackers are the main reason for a drain. If you have a 1300 do not connect an Optimate through the socked as this causes the bike to fully discharge the battery. Mine did this and lost all power to the point you couldn’t even unlock it nor switch it on.

Go direct to the battery or use the BMW charger.

Barry
 
Trackers are the main reason for a drain. If you have a 1300 do not connect an Optimate through the socked as this causes the bike to fully discharge the battery. Mine did this and lost all power to the point you couldn’t even unlock it nor switch it on.

Go direct to the battery or use the BMW charger.

Barry
Which optimate though? The 4 quad is LiPo compatible and works fine with mine through canbus.

The previous gen ones will suck the life out as they’re not compatible.
 


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