BMW R1200RT/R1250RT Forum

Hi All,

After 3yrs of irregular use* my Oxford Oximiser 3X Battery Charger appears to have developed a fault. When I connect it to a battery it almost immediately lights up to show 17.8v, then just sits there displaying 'Standby'. I've tried this with the battery on the bike and a spare LifePod4 Lithium Battery and the charger has reacted the same with both. Pressing the 'Mode' button doesn't do a lot either. I guess it's knackered.

So, any recommendations for a new one (for a '18 R1250RT)?

*I purchased the charger in Dec '20 so it's just over three years old. I use my bike regularly and throughout the year so it's not like the charger has been plugged in doing it's job for months on end for three winters. The number of 'hours' it's actually been used is really quite low. Quite disappointing for something sold as a premium product.

I've always use CTEK chargers without any problems, they diagnose and asses the battery then charge accordingly same as most micro-processor controlled chargers available today until I got my RT. I found it kept tripping out/ timing out when plugged in via the accessory socket as the currant wasn't enough to keep the canbus interested and active so the socket would shut down. I ended up buying the BMW charger from Barnstormers as they were the cheapest and it just plugs in via the socket and does what it says on the tin.
To be fair they are all pretty much the same but you may need to connect direct to the battery and you'll need to check if it's compatible with both types of battery.

It is not well known but look up BMW charger part number 61432408593. It is a BMW branded Ctek charger and costs circa £90, I just checked on Google. I had it last year for my car and when I read the instructions it said it was also for BMW motorcycles and Canbus compatible. I bought the accessory socket adapter and it works perfectly. Periodically waking the bike and keeps the battery healthy, I can confirm this from the bike tracker app have. No idea why the motorcycle department doesn’t sell this, as it is lithium compatible as well, but I can take a guess .

Capt Sisko wrote: ↑Wed Jan 17, 2024 8:58 amAny recommendations for a new one.

From this thread and poll, the Optimate 4 Can Bus edition is most popular, viewtopic.php?t=6035&hilit=battery+chargers

As per the pole

David. wrote: ↑Thu Jan 18, 2024 12:13 pm From this thread and poll, the Optimate 4 Can Bus edition is most popular, viewtopic.php?t=6035&hilit=battery+chargers

Thanks for that link and that's pretty much ties in with what I've read up about over the last couple of days. Optimates seem to have a good name.

Cheers

I have an Oxford one! Lasted a year!

I got an optimate and I'm 17 years in

Just had email from Nippy Normans. Optimate 4 - Quad program charger does lead acid normal and BMW + lithium normal and BMW . Comes with various cables/adapters for £89.00 part no WUN-20190-400.
Seems to be best price I can find but make sure you look for the QUAD program edition as they also do a dual program which as far as I can work out will not wake the canbus.

You do not need the canbus version unless you plan on using the auxiliary socket to charge the bike

Too many people get hung up on the can bus version for the wrong reasons! The only reason you need a canbus charger is if you're not charging direct to the battery. It will not affect the bike in anyway having a standard charger and pigtails.

I would prefer to have pigtails on the bike and plug it in that way I have a power source for the tyre inflator that won't trip out when inflating tyres which I have seen on many occasions!

Nothing worse than been stranded with a puncture to then be left stranded by the bikes system tripping out because the pump draws too much power

This is more than good enough

https://www.sportsbikeshop.co.uk/motorc ... ,3203,1186

Unless you have a lithium batter of course

Use a cheaper model that comes with pigtails. Easier to fit to other bikes.
Mine is the Optimate 4. At the time of purchase, it was around £72.00

Hello,
I read in the german version of the Haynes Manual for the R1200 LC that it is also important that de charger doesn't give voltage peaks that could damage the sensible canbus electronics.
I dont think that a decent charger gives these peaks but can you be shure?

Gerben van den Berg
R1250RT soon...

GvandenBerg wrote: ↑Wed Jan 24, 2024 5:37 pm Hello,
I read in the german version of the Haynes Manual for the R1200 LC that it is also important that de charger doesn't give voltage peaks that could damage the sensible canbus electronics.
I dont think that a decent charger gives these peaks but can you be shure?

Gerben van den Berg
R1250RT soon...

Hi and welcome to the forum

This is only if you are charging through the auxiliary port

Interesting discussion...

(2021 R1250RT)

I had paid the big $$$ for the BMW Motorrad Battery Charger Plus "smart" charger, and have used it religiously whenever the bike was not ridden regularly and all through the winter "wheels up" months. The charger looked like it was charging the battery, but I was surprised last summer when the service shop said I needed a new battery -- after only three (3) seasons. I was plugging the charger into the on-fairing accessory receptacle as advised. [photo #1 shows "full charge" notification when connected through CAN-BUS for charging]

Based on this discussion, I just this week connected the charger directly to the battery terminals. For the first time (for me), after the battery became fully charged the display screen on the charger changed to say "Charging Complete/Battery mainten." [img][photo #2 shows "Battery Maintenance" mode, only when connected directly to the battery]

So, it appears the "smart" chargers will charge a battery through the CAN-BUS connection, but they will NOT perform the designated battery maintenance routines unless connected directly to the battery.

Live and learn...