Not a bicycle, but my ebay record was 43 seconds.

I had a rather expensive old knife, I did a good write up, and posted with a reasonable starting price and a BIN of $50 above the highest price I could find in completed listings. As I said BIN 43 seconds after I listed it. I wish the people who told me I was stupid paying $250 for a knife had been around when I sold it for $649.

But bicycles are harder because the shipping is sooooo...... much more.