While your at it rebuilding that frame I would replace the chain stays. That curve in the chain stay will probably cause your chain to rub on the low point of the curve in some low and medium gears. I had this problem on my CWC Klunker. That frame is designed to work with a big chain wheel. I also had problems banging pedals with the original 6.5 inch one piece crank as the bottom bracket was too low for my single track coaster brake riding on my CWC. I used 5.5 inch cranks and it was a lot better. Also, thin pedals help a little. My Schwinn DX and Colson Klunkers have none of these problems with 6.5 inch one piece cranks. I did have a lot of fun with the CWC for 3 years and I rode it single track a lot. You get used to short cranks. If your frame is the same as mine was, and it it looks like it might be, the 175 cranks could be a problem on single track rocks and roots. 175 is one centimeter, 1/3+ inches longer than what I tried originally so you might be OK on smoother tracks. All I know is I was always banging with the CWC and I never do with the new klunkers. Someone else here on RRB recently built a CWC Klunker and used 7 inch cranks without a problem so perhaps it is individual riding skill or maybe there are different CWC frames that look similar but have a higher BB or it could be better with a freewheel? I might have been able to get use to it but I am not a strong peddler and need to keep peddling, I can't get enough speed to coast up hill to clear the boulders and roots and there is no back peddling to clear obstacles on mine with the coaster brakes. Yours will be better with a freewheel. It will be interesting to see if your frame works better for you than mine did. The biggest issue might be the curved chain stays. I just let my chain rub and pound the paint off and kept riding, but I would have preferred that it not touch the stays. I did change my gears to get better clearance, but the chain just cleared the stays with my single rear cog. I ended out with two similar sized gears front and rear that made the chain parallel top and bottom and were big enough to just clear the stays. The best compromise I could come up with for my riding was 24 front and 23 rear. If the chain stayed tight it was OK, when the chain stretched it banged.
