£55 from Berkshire Cycles. They’re happy to post them out. Smashed mine last week when a rock was flung up by the front tyre. But repaired rather than replaced.
To make it like a normal bike you’d need to set PP to about 5%. Bike weight difference is about 8kgs, times an average rider output of around 3 watts per kg = 25watts max as assistance. 25 watts as a proportion of 560 max from motor is 5% rounded. With peak power set that low the assistance...
If you are all replacing cassettes because of wear to the bottom few cogs of the cassette then you need to increase the size of the front ring, then you’ll use more of the cassette more often. 36T is the sweet spot for the front ring.
I’d always run peak power at 100% as there’s not massive amounts of power available, why limit it further my reducing peak power plus it’s not like these bikes are short on battery range.
Chris at BC told me the same, then I was told to use the dielectric grease by a mechanic at Specialized head office in Chessington! It’s silicone based so safe on seals, I was told, plus the amount used is tiny and on the connector seals only. Using Vaseline or general grease is not recommended.