About a year ago, which coincided with owning the bike for about a year, my rear brake disappeared. After a bleed by the dealer it was perfect again. Now one year later it is beginning to get weak again.
With so many folks having the same recurring problem - even after Triumph's new and improved bleeding procedure - I doubt improper brake bleeding is the problem. And even folks who have had parts replaced under warranty have had the same problem recur.
I would suspect there is a design flaw in the rear brake system itself. Except that doesn't really make sense to me either, since the flaw would have to be somehow allowing air into the system. You'd think proper rear brake design and maintenance would be a solved problem. The Rocket's rear brake isn't truly unique or revolutionary.
I guess I'm just going to have to add "bleed the rear brake" to my list of routine maintenance items.