I don't think it is an Aluminum bore.
8.8 ft. lbs. @ 2500 RPM
Precision machined aluminum alloy crankcase with heavy duty cast iron cylinder
Ball bearing support shaft for long life
Fuel shut off for safe transport
It says cast iron cylinder but looking at the pics I think that must mean a cast iron liner. The HF E-mail description actually says it has a forged steel crankshaft and commercial grade ball bearings but I would have to actually see that before I believe it!
The description I quoted above from the HF website says a cast iron cylinder but the link below seems to indicate an Aluminum cylinder.
Maybe that is an Aluminum cylinder with an iron bore?