respaced the rear axle for a 6 speed ird freewheel thinking i had both the frame width (mb gr) and the rd (suntour cyclone gt) to handle the new addition. while working on the bike, i realized the rd could either dial out the small cog and reach the big 28t cog or i could space the axle wide enough for the chain to clear the frame for the new small cog thus preventing the rd to reach the far enough inside for the big cog. but i couldn't find that perfect spacing yet to take advantage of both. so i rode it today with the small cog dialed out with use of the rd adjustment screw so i would have access to the 28t cog for a couple hills in town. and this seemed to work fine for most of the ride until i actually shifted down to the 28t for the first time. i was doing only about 5 mph (fortunately no faster) when i shifted and the rd shifted too low into the rear spokes. it sounded so awfully sad. everything seemed ok though, that problem was just a matter of adjusting the other rd screw correctly. but it's obviously back to the drawing board to find a rear hub spacing that might work for both the frame and the rd.