Fortunately it can be replaced with a stock washable filter. The riding position is competent, but not all that comfortable for long trips. Triumph also didn't design the 'Bird for highway pegs or floorboards, either of which are mainstays for long-distance riders. Gas mileage is okay, but nothing to boast about. But the first thing you really notice about the bike happens whenever you stop.
People come up and ask about the bike.
They talk about Triumphs they used to ride. They can't get over the fact the company's back. I get mired in chit chat when I want to ride. So I plug them with both barrels full of a coupla pithy anecdotes on Triumph's history and design and then leave them gaping in my dust when I blast off. The Thunderbird was introduced in 1950.