That's the thing. cwah did not get 5,000 or 10,000 miles out of his bikes, he killed them well before that.
If you take a bike like the Karoo or the Bermuda with Bafang motors, they'll go well over 5,000 miles. Woosh bought 10 clutch units for Bafang SWXes back in 2011. They still have a couple...