I would call customer service in Georgia - (678) 854-2010, extension 2064. When my saddlebags never came in last year I called and talked with Peter and found out that Triumph had rejected the entire first lot from the supplier. I still didn't have my bags, but at least I knew why and I appreciated Triumph rejecting the bad parts.
Maybe you will find out whats going on with this issue and if they tell you a new part is around the corner, then wait, otherwise tell them you can't run around on a bike not knowing the speed and get them to send out a new one.
Called the number. First Peter said to take it to the dealer and get the speedometer replaced and I told them that they said they wouldn't do that and then he said "oh wait - were not doing that anymore - were still waiting to hear from the UK" . I asked If triumph would give me a loner bike with a working speedometer while I leave mine at the dealer waiting to get fixed. He said they should, so I am going to call them tomorrow(closed on Mondays). I afraid to ride my bike much since the speedo screws up most all the time anymore, especially after the warning ticket.