I have had the "no warning" battery failure occur a number of times. On my R100GS/PD the OEM battery lasted 10 years, started over and over, then in the middle of a trip - no start, showed 12 volts until a load was placed and then nothing. I've owned my 2018 R1200RTw since new and it still has the original battery; thus I am looking for a replacement. My Harley Electra Glide rarely gets more than 2 years from the battery (heat and vibration); several times the battery has failed while I was at a Harley dealership.
A feller that knew quite a bit about BMW bikes went by the name of Snowbum; he is recently deceased. He has published a lot of info about many BMW-related things. His article on batteries is dated 2024, so this must have been something that he was doing right up to the end. It is worth reading his comments -
bmwmotorcycletech.info
I did find an assortment of batteries available from Battery Mart. I have purchased from them previously - their prices are pretty good. An EarthX LiFePo4 battery suitable for the RT is available for $259 with free shipping in the CONUS (continental US).
A feller that knew quite a bit about BMW bikes went by the name of Snowbum; he is recently deceased. He has published a lot of info about many BMW-related things. His article on batteries is dated 2024, so this must have been something that he was doing right up to the end. It is worth reading his comments -
BMW motorcycle batteries, chargers, initialization, flooded, lithium, LiFePO4, lead-acid, de-sulfating
New Battery, LiFePO4,lithium and AGM/VRLA batteries, BMW, motorcycle, motorcycles, filling, charging,load,test,load-test,anti-sulfating
I did find an assortment of batteries available from Battery Mart. I have purchased from them previously - their prices are pretty good. An EarthX LiFePo4 battery suitable for the RT is available for $259 with free shipping in the CONUS (continental US).
the original battery in my '20 1250 RS lives on a battery tender when not in use and, using the old "seat of the pants" battery testing protocol doesn't show any signs of misbehaviour. This seems to be the norm for my MC batteries ever since I started just keeping them on my battery tenders (real thing not a cheaper knock off) But since I'm a firm believer in PM and being prepared it's time to consider a replacement. At 70 y/o even though it's a 1X purchase I'm at least a little loathe to purchase a $200 Opimate charger plus a nearly $300 shipped LiFePo battery. But more research may help me turn on corner?
