tl;dr
Does anyone know of an existing hydraulic brake lever (eg (like this)) that can clamp on a 31.8mm bar or can anyone think of a way I can hack/bodge/modify one?
I'm thinking similar to how CX bikes do it with cables except I want it not inline (separate brake) and hydraulic
Context:
- I only have a right hand
- I'm building a road bike with drop handlebars and a hydraulic disk brake (Shimano r8070, right-side, front brake).
- I have been happy with a single brake for 20+ years but since having kids I feel like a second, backup, brake would be wise
Out of the box solutions welcome!

https://www.singletracks.com/blog/mtb-gear/outbraker-converts-hydraulic-disc-brakes-to-single-lever-system
https://bicycles.stackexchange.com/questions/42450/bicycle-designed-for-one-arm-usage has an answer for flat bars.
– mattnz Jun 28 '19 at 22:04