I did that to my Suzuki Intruder, but I'm so proud of my Triumph I don't want to take the decal off. Here in the states people have to read it to know what it is.
personally prefer the clean lines on the tank. Dont worry, still have the 11 triumph badges on the engine case, gearbox housing, on the running boards, pillion pegs, the saddle bags and the pillon seat back.