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Mosaic
Mosaic RT-Zero Road Bike
RT-Zero marks a new chapter for Mosaic road, where titanium precision meets carbon discipline.
Builds starting from $15,000
Enquire about this bike Start with a stock frameCan’t come to California?We can bring the build to you. Wherever you ride, we’ll work with you to create and finally crate up your new dream bike and deliver it to your door.
RT-Zero is Mosaic’s most advanced road chassis to date, a complete re-think of their long running ITR platform. By integrating the Zero Ops carbon seatmast with Mosaic’s custom-butted titanium, RT-Zero introduces a new balance of sharp response and long-day comfort. What stands out to us is how it carries forward everything we count on from Mosaic: precision handling, clean lines, rider-first geometry, while adding a new layer of ride tuning that makes the bike feel both quicker and calmer than anything they have built before.
The D-shaped mast and compression-molded topper provide stiffness and comfort in ways a round post cannot. Bridgeless 12 mm seatstays flow into a CNC collar for a clean, aligned junction that rides as refined as it looks.
The full package is modern without compromise. ENVE In-Route fork and one-piece cockpit keep the front end tight, routing is fully internal and a T47 bottom bracket keeps service straightforward. We run 32s in Marin though clearance goes to 35. Geometry is rider specific and this is Mosaic’s lightest road chassis to date.
Mosaic’s CNC details such as dropouts, collars, head tube, and BB plug give every interface a precise feel on the stand and a distinct visual signature up close. The Shadow Titanium finish with painted carbon accents is subtle, with Artist Series options for those who want more.
Read our launch story with Mosaic founder Aaron Barcheck here
Ordering process
Whether you’re already set on a certain make and model of frame, or still have some questions about how to go about your build, drop us a line and we can talk through your options. From the first detail to the final finish, we'll help you dial in the perfect set up for your next dream bike.
Enquire about this bike
Tell us a little about how and where you ride and we will come back to you, usually within a working day.
The AC Journal
From the Journal
September 2025
Mosaic’s RT-Zero Project: The Inside Story
The Mosaic RT-Zero feels like what happens when a titanium builder with nothing left to prove decides to reset the bar anyway. For more than a decade, Mosaic has refined its road machines into benchmarks of the category. But when a team like that decides to start fresh, the result isn’t a small step forward. It’s a complete rethink of what a titanium road...
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