You can’t really compare the air cooled and water cooled bikes. More than the Bonnevilles, the new Speedmaster has few similarities to the older one. That’s not to say the air cooled model isn’t a great bike. It was in the top group for sales for several years and was probably the best all round classic cruiser in its class. It certainly was my favourite. When I was selling them, Triumph Australia called me ”the Speed master” because I was selling roughly one a week and outselling every dealership in the country for them, so I do know.
The new one, in my opinion is superior in many ways. It has a substantially bigger engine (1200cc) high torque, water cooled, 6 gears in place of 5, ABS and traction control, ride by wire, riding modes, cruise control, lots of factory accessories still available.
Negatives are that luggage options are limited and the seating perhaps isn’t quite as comfortable.
The riding position also is also very different. The air cooled model had flattish bars and forward controls. The new one has slightly less forward controls and bars that pull back a long way and in many way has an older, more retro feel. It makes me want to put on a leather helmet and flying goggles.
My advice is to try to ride them both. Both wonderful bikes in their class but quite different.