Originally Posted by
xroadcharlie
Perhaps there is something close, or lower that will work If the crankset is good. The point being using an worn out chain ring with a new chain and cassette isn't a good idea. Even the same size new ones might be fine with a 32T large rear sprocket.
39 is as low as you can reliably go on a 130 mm BCD. I've seen 38s, but for the single-tooth gain they aren't worth the bother. At the first hint of wear on the teeth and chain, the chain starts to skate over the nuts or spacers between the rings.