well, I just got my first pinch flat on Monday (at least I assume that's what it is. I got a flat tire without any visible penetrating objects in the tire). Also beat the crap out of the rim (I noticed a crack in it when I pulled the tire off last night). Rode over some rocky, sharp terrain in the Cochiti Canyon area. I guess that I'm going to have to look into this conversion. In the meantime, I bought a cheap 120/90x19 rear tire and a new tube so that I can get back in the dirt this weekend. Does anyone have a good (ie cheap) source for the spokes and rim? Is it worth it to have the rim welded? The crack is thru the bead area (about 1/2" long total). Thanks Tracy