Well, in the spirit of keeping ETLB moving, here's the story so far about converting a set of mountain bike hydraulic disc brakes to fit an existing 1600R axle. I wanted differential heel brakes to aid in ground handling. I've saved a PDF file in the UK Minimax forum. The file has a lot of photos but I can't see a way to save the file on here? So if you are interested, you can view it in 'files' on https://www.facebook.com/groups/MinimaxUK but unless you are already a member of the group, you need to join.