i agree on the fast wear on the racer tires but i'd be curious on how much faster as there's quite an interesting gap in what kinds of milage people are getting on their avons. I'm about to hit 5,000 miles in mine and they almost look new whereas people on the forum are reporting near bald tires at 3,000 mile.
The standard Avons are a sidecar tyre, and the Blockley is a car tyre. Both have a profile suited to a three wheeler for road use.
I suspect if you use a bike tyre, you'll wear out the middle in short order. A motor bike leans and changes angle so wears most of the tyre - a three wheeler won't, so will wear a narrow band. The reason that racers use them, I think, is that the rubber is softer, so more grip, and the shortish life is not a major problem.
If you are wearing out standard tyres a bit quickly, you'll wear out bike tyres a lot faster!
I could ask a racer, but I think I'm right.
