no i checked, they are iso 406. you can see this listed on the tire that came with the bike. if the rim were not a 406 then this 406 tire would not fit. the other 20 inch is a 431 or something like that. the 431 does not fit the schwalb tires so that is bad. but luckily this bike rims do fit the bigger tires. i ordered to marathon plus 1.75 today. i think the size is not necessarily wide but looks more like height, in which case they would easily fit. i will post pics when i get them, if they fit. if not, I will put the 1.50 marathon on it.

regarding the rack. my mvwave panniers are over 12 inches long at the bottom and 15 inches at the top. these are huge. so if you put on ortlieb bike packer panniers, big by the way for cross country touring, they are only 9 inches wide at bottom and 12 at top. so you could easily fit those with absolutely no heel strike even with clips I imagine.

i weigh about 180 but normally about 170. if i can drop my weight, i imagine i can safely put an extra 35 lbs of gear on the bike. i think the 200 lb weight limit is fine, but i think with the extra big tires, this thing can handle a little more weight. 220 maybe.

yan has not answered me on this