The dropouts look identical to my Apollo roadie, which don’t allow any adjustment. Papa, you re-building this bike into a fixed gear? If the dropouts aren’t adjustable you’re gonna have serious problems getting the right chain tension…
magic gear ratio, round file, you might be ok. rookie mistake
You could also try:
b[/b] using a ‘ghost’ chainwheel (see the ‘ghost’ chainring between the captain’s chainwheel and the stoker’s chainwheel on this tandem - CTC Forum • View topic - Pictures of your bike(s) - it looks cool but I don’t know whether its really practical in the long run); and/or
b[/b] a half link chain connector or a half link chain (which should double your chances of getting your ‘magic gear ratio’ - see Shackle 85 Link Half Link Chain ),
to try and get good chain tension with vertical dropouts.
Of course, if you use any of those solutions you will still lose tension as your chain “stretches” – so you really want some way that you can easily adjust the chain tension. I reckon the best solution is to get an experienced frame builder to change the your vertical dropouts to track ends, or (failing that) to use an ENO eccentric hub.