I've looked all over for cheap tires- the wally world here is now out of the really smooth bell cruiser tire and has these with a lozenge pattern- if that makes sense- the pattern only is raised a hair off the tire and I think it would work for a friction drive... I may buy one a my back up replacement. I've decided that I'm going to mount a friction drive on my old really nice Schwinn MTB. I don't ride it so it's just collecting dust. My plan is to get the major parts of the drive set up this weekend. I have a feeling it will be a tad faster than the Madwagon and as much fun to ride!
Target only carried MTB tires- way to rough for my needs.
The KMart around here is out of my way and I haven't checked the bike shop selection- you can always sling it- put one shoulder and you head through and carry it home that way