Next door in F800GS forum there was a couple very long threads on chains that broke destroying rear ends some within warranty some not. Some at speed on the highway. I did not have an issue with the chain on my 800 but you have to oil the bloody thing reguarly.
The BMW standard drive shaft with u-joints if Bruno can install grease fittings may well be best.
How long they will last seems to be the unknown, we just do not like not knowing when it will go out.
Originally Posted by Anorak
How many broken chains have you seen? If any, how many went through the engine case. If any, what condition were the chain and sprockets before the chain broke.
A failed u-joint can render the swing arm unserviceable.
I remember, now, the F800 had a recall due to failing chains.