Using one with a cromo railed Brooks Pro and experiencing some slippage aft. Tightening it up as much as I dare and it still moves back over time. Anyone experiencing similar?

I had some issues with mine to start with. I eventually cured it with some precise greasing of particular parts…

– Grease the side bolt threads that adjusts fore/aft and tighten very tight, re-tighten after riding for a few miles.
– Don’t grease the black inserts that rotate up and down or they will slip.
– Grease the bolt threads on the 5mm bolt that adjusts up and down tilt.

I should probably add that I did the bolts up extremely tightly, almost crank bolt tight.