Yea, thanks; I thought dubbelop was a bit confused. Don't see that Cdale ever put a carbon fork stock on a tandem. As well, the funtional rotating weight difference between the Mavic 719/Hugi wheeels and the Mavic 520/Shimano wheels isn't significant. Any difference in their weights is related to hubs not rims. BUT, the functional difference between either and the Bontragers, with their weight advantge and huge aero advantage, is really big. Trust me (OK, so don't trust me, ask somebody else who you already trust who has them).