BMW R1200RT/R1250RT Forum

Can I run a trickle charger (Optimate)on my’19 RT without disconnecting the battery from the bike?

Yes! No problems whatsoever

If its the none canbus type then you need to connect straight to the battery

It if is the canbus compatable type you ought to be able to plug it in via the power socket on the RH side of the fairing or the one below the passanger seat. The former is usually the most convenient though.

You can usually just connect a pigtail to the battery and go direct, Most trickle chargers come with such a pigtail. If you research the Internet, you should find some Canbus friendly chargers.
Note: if you have converted to a lithium battery , it is going to require a special charger

Randyjaco wrote: Fri Jun 13, 2025 4:36 pm You can usually just connect a pigtail to the battery and go direct,

Plus with that set up(I did it on mine)you can run higher load out of the pigtail

Stu wrote: Fri Jun 13, 2025 7:37 am Yes! No problems whatsoever

If its the none canbus type then you need to connect straight to the battery

I came here to find this out too! What about for a 2016 model, is it safe to use an old Deltran Battery Tender direct to the battery? It's a 750ma maintainer that I've used for years on different bikes and car batteries. I read the manual and it's very strict about how it's charged, as I'm sure everyone knows here.

I have not taken the seats off yet so I don't know if there's a pigtail already but I have looked at the battery itself and it does not appear to have anything extra attached to it.
Thankyou for any insight, this is my first BMW and I want to learn all I can.

on2wheels wrote: Thu Apr 02, 2026 1:33 am I came here to find this out too! What about for a 2016 model, is it safe to use an old Deltran Battery Tender direct to the battery? It's a 750ma maintainer that I've used for years on different bikes and car batteries. I read the manual and it's very strict about how it's charged, as I'm sure everyone knows here.

I have not taken the seats off yet so I don't know if there's a pigtail already but I have looked at the battery itself and it does not appear to have anything extra attached to it.
Thankyou for any insight, this is my first BMW and I want to learn all I can.

Connect straight to battery as I did on my 16.I ran DC to DC as I had no power in my garage(ran it off a leisure battery) worked a treat.

That's good to hear, thankyou.