BMW R1200RT/R1250RT Forum

Not surprisingly, the Optimate 4 Can Bus edition is proving most popular.
Currently available from BikespeedUK for £56.95, OptiMate 4 CAN BUS BMW Motorcycle Battery Charger (bikespeeduk.com)

If you would like to be thrifty and happy to bolt a pigtail lead to the battery (or use croc. clips),  then for £15 you can have this offering from Halfords,
Halfords 6V/12V Maintenance Charger | Halfords UK

Then again, if the charger must have BMW on it, Nippy Normans will happily take £139 off you for this,
BMW charger for R1200GS LC, R1250GS, K1600GT/GTL and all models after 2004 (nippynormans.com)

If you're happy just to use croc. clips, how about this for a tenner from OnBuy.com,
Car Battery Charger 12V Automobile Motorcycle Intelligent Pulse Repair on OnBuy

Levisp wrote: Anyone using a solar battery charger ?

I looked into solar power but you need to spend big for a decent result.The Optimate DC-DC is/was the most sensible answer for me.

Just to be different - A CTEK MXS 5.0


https://www.smarterchargers.co.uk/products/ctek-mxs-5-0-battery-charger

Steve398 wrote:Just to be different - A CTEK MXS 5.0

There you go Steve, get your vote in.

One thing that the poll does show is that there are plenty of alternatives to an Optimate 4 Can Bus edition, charging via the onboard socket.

Some new R1250RT's won't accept a charge via the onboard socket, keep it simple and go directly to the battery.

BMW R1200RT / R1250RT forum - The BMW R1200RT/R1250RT forum

David. wrote:
Some new R1250RT's won't accept a charge via the onboard socket, keep it simple and go directly to the battery.

As far as I know the 2021 RT works fine from the fairing aux socket, not from the rear one. Mine charges fine through the front aux socket. No need for direct battery connections.

keith1200r wrote:As far as I know the 2021 RT works fine from the fairing aux socket, not from the rear one. Mine charges fine through the front aux socket.

Found this on BMWLT.

"I use an Optimate 4 through the aux socket on the fairing and it works fine. The one near the pillion seat doesn't seem to work for charging."

Oldnickers wrote:Initially I thought it was because I was using the rear charging port but the fairing one yielded a similar problem.

This problem was with a BMW charger!

David. wrote: Out of interest, have you tried using the rear socket and which battery charger are you using, BMW or Optimate 4 Can Bus.

This problem was with a BMW charger!

Yes, I have tried the rear socket - doesn't work. Optimate 4 charger. Front one is fine. I have seen other comments reporting the same issue.

keith1200r wrote: As far as I know the 2021 RT works fine from the fairing aux socket, not from the rear one. Mine charges fine through the front aux socket. No need for direct battery connections.

Mine charges fine through rear socket, BMW charger

Well, there you go then, confirmation that the onboard socket charging problem is bike specific not down to which charger is being used, BMW or Optimate 4 Can Bus.

PeteM wrote:
Mine charges fine through rear socket, BMW charger

Is it the 2021 model?

keith1200r wrote: Is it the 2021 model?

Well according to my profile over there <<< what do you think?

Can't beat a good film, https://youtu.be/wbzKvGyr6Yo

LIDL middle aisle have this Ultimate Speed battery charger for £12.99, https://youtu.be/IYv4S19QOJQ