Helicopter tape, a bit fiddly to fit in the area needed but well protected when completed. Just make sure you buy quality tape and not some of the cheap thin stuff.
Mines been returned today for a full refund as both upper bearing surrounds had cracked and one of the lower ones in the blue paint was just showing slight signs. A shame as I really liked the bike but no spares to repair or stock to replace the bike. Do I wait and hope that the newer Haibikes...
I'm not too bothered as it's under guarantee and if the paint is cracking then something is flexing that shouldn't be. It'll be interesting to see what Haibike's response (ha!) will be.
The covers must vary in secureness on the allmtrn as there is no way mine could work loose, it takes a huge effort to remove it with it visibly bending before it pops off.
Mine dropped the chain a couple of times last week but the mud was a terrible mixture of clay and fallen leaves. The chain stays were almost jammed up with the stuff. Pain in the backside to get the chain back on too as the chain device had to be removed.
I also use a standard work stand but to lube the chain I just use a plastic clothes peg clipped into the chainring which allows you to turn the pedals backwards.