Originally Posted by
TejanoTrackie
The stock wheelset is a Fulcrum Racing 5.5, which are the Cervelo specific version of the Fulcrum 5. I don't think they are tubeless ready, but am not especially keen on going tubeless anyway. The reason for going wider than 25mm is to handle the occasional forays on gravel/dirt roads or really bad roads.
Those Fulcrums are totally decent for stock wheels. I can't speak for the particular off/crap roads you find yourself on, but I would feel safer rolling into unknown territory on tubeless 25s rather than clincher 28s. Taking pinch flats out of the equation is huuuuuuuge.
When you test ride the two, are you going to be able to try the tires you want or will the bikes be on their stock 23s?