Yes, you're right. There are quite a few visitors who stroll up the parking lot at Deals Gap during the meet, admiring the old 2-strokes. Occasionally there's one who starts explaining to us how an H2 can do 5th gear wheelies, and they have hinges in their frames, and all the other folklore about them. I rode my H2 to the local motorcycle dealer a few years ago, and a guy in the parking lot told me about the time he was doing 170 on some motorcycle he owned, and his buddy on an H2 flew past him like he was standing still. The only thing I could think of to say was "Must not have been stock."

An H2 was one of the fastest things on the road at the time, but it was rated 74 hp at the crank, so about mid 60s at the rear wheel at best, and weighs in the mid 400 lb range wet. Even midrange motorcycles today, like a Yamaha FZ-09 are lighter, more powerful, and run a quarter mile quicker.
That's not to say you can't hop up an H2 and make it very fast. The non-supercharged 750 drag record is still held by an H2. Larry Smith's H2, driven by Brian Pretzel, ran it in 7.776 seconds at 170 mph.