Originally Posted by 3alarmer

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...this is a heavily modified, but not obnoxiously so, PX-10 in the randonneur school.
I don't know the year (I'm not very good with dating these bikes), but it's a frame that was made with 120mm spacing in the back. So more or less the classic ten speed. In this case, it has one of those swell ultra six freewheels, to fit six cogs in the space of five, and a 6-8 speed chain width, to accommodate that modification. The bar and stem are something from Asia (SR, maybe), and the bar has a randonneur bend.

The freewheel range goes up to 28 in the largest cog, so I recently changed out the rear derailleur to an early Shimano Tourney that will work. It's almost identical in construction and capacity to the early short cage Crane derailleurs, but this has a steel pulley cage, so is a little heavier (not much, but a little).