Hacked, Conversions and Trailering"Harley Sidecar, Conversion Trikes and Motorcycle Pull Behind Trailering Enthusiasts"
A forum for the discussion of your sidecar, Conversion Trike or Pull Behind Motorcycle Trailer.
I probably won't be a lot of help but on my Sportster trike I run a Michelin Commander II on the narrow 21" front rim. It had the best compound I could find at the time and it has held up pretty good. Still being a Sportster I don't have the weight but still have the scrubbing effect. If I could find a rear tire in the narrow 21" size I would try it on the front, they don't make rear tires that small. Hopefully someone with a rig will chime in and give you information.
Also, mileage varies a lot depending on the wind direction and wind speed. Varies from about 20 mpg to 38 mpg when crossing windy Kansas. Started carrying extra fuel when touring after almost running dry when I first started driving a rig.