You should change the final drive oil in your BMW R1250GS every 12,000 miles (every other oil change). It's quick and easy to do it at home with just a few tool.

Squeeze bottle: https://amzn.to/3U9O8fO
Oil: https://amzn.to/3w9hV0o
Torx bits: https://amzn.to/4ddFB4m

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