NateZipp wrote:
Hi SummitAK, and Slowtwitch,
Nathan from Zipp here. I am the product manager for Zipp bar, stem, and seatpost. Happy to answer questions for you. The Center Cap is compatible, there is a finish difference, but it will fit.
The Extension towers are not backwards compatible. The old VUka Aero/Vuka Stealth was built around a ±3° tilt. The new Vuka Aero is designed for +10° the mating surfaces are no longer compatible, sorry.
Best
Nathan
Thank you for following up with detailed info Nathan. I've built up several bikes with Vukas and they are great bars. The limitations have generally been the pad rotation/stack change variables (plus extension bolt access in narrow config!) and the minimal extension tilt. So it is a bummer about the lack of backwards compatibility.
If I understand you correctly the compatibility issue is due to the mating surface tilt area profile in the top of the previous basebar not matching the profile of the new extension risers. Zipp came through in the past on the Vuka Low-Stack extension clamp option. Assuming the extension riser bolt centers are the same, and because the tilt functionality moves to the top of the extension riser stack, maybe consideration could be given for providing an aluminum 5 or 10mm extension riser adapter with the bottom machined to match the older bars and the new tilt profile at the top to match the new extension clamps and risers? But maybe I'm looking at the incompatibility wrong?