Originally Posted by
shafter
I have used an adapter and was very pleased with it. You will have to buy a threadless stem though. I used an adjustable threadless stem for maximum adjustability.
A quill would be cheaper though. An ebay adapter and stem will run you at least $30.
Plus the cost of new bars/tape, assuming he goes from 26mm to 31.7 on the bars.
I did this on an old Trek 2500, went from a quill to an adapter and 31.7 bars. It was heavy but it allowed me to play around with stem length and angle by trying multiple stems, and I was much happier with the compact drop bars versus the traditional bars the bike had initially.