Lube the splines...

[Journeyman]

I don't mind a little extra service, but is there any reason we're doing this every 8000 miles? Have some bikes driveshafts worn out or showed signs of wear if not frequently lubed? I've owned several shaft drive bikes and never had this as an issue. Why wouldn't Triumph recommend it? I did some searching and couldn't find anyone saying there's a issue with this bike. Other big bikes are like ours, and don't recommend it at all, and if they do, it's more like every 16k miles.
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Just wondering if I'm missing something.

There's no recommended interval at all, so it's up to your intuition. I'd say most folks here will never do it. My '11 Roadster had two FDs go out, so I err on the side of caution and do it about every other rear tire change, about every 9,000 miles. That factory lube will dry out, so......