i have a 1972 puch with 700c rims and a regina 5 speed freewheel, 120mm frame spread. i also have a set of alloy 27" wheels which fit fine from dumpster inc. the 27 has a 6 speed shimano sis hg20 freewheel. it seems to be an "ultra" because it fits right in the 120mm with no force. i just had to adjust the brake pads to get the 27 to work.
question; will the shimano 6 speed freewheel fit on the 700c 5 speed wheel? and question #2; are there different cogs available for the shimano sis freewheel?
i couldn't measure the shimano hub directly and i had to do some adding and subtracting to come up with a number. i came up with 124mm and the frame measured 121mm but no force was required to fit the wheel, more like the original hub. i think i will run it by the lbs since i have neither a tool for the regina or the shimano and hear what they have to say..
i went for a new 130mm cassette wheel and an 8 speed. i moved up from a 28 big cog to a 32 and had to go for a new rd. grand dad here and i like the the 32t grand dad gear.
the 130 wheel goes on with little problem, so i will not bother with cold setting the frame. since i was putting a new rd on i had to set it up in any case.
Just remember, if you experience problems with the shifting performance, ask you local bike shop to check the hanger alignment. But glad to hear that the upgrade went smoothly so far!
i found a set of acera shifters with cables on ebay for short $. the next upgrade is in the "mail".