Originally Posted by rockmuncher

Dunno. But my dereilleurs are 105. The other confusinating thing is my new bike is all Ultegra and comes out with 39/53 from the factory.

Maybe its only a problem if you mix Ultegra running gear with 105 dereilleurs

BTW, I was looking at the programme for the upcoming masters games in Adelaide and they mention a track event called the Derby. Any idea what its format is?