Frame

Custom Mosaic GT-1 i45

Drivetrain

Shimano GRX 12sWolf Tooth 42T Chainring
GRX 9-45T Cassette

Wheels & Tires

Chris King 44 ARD
Pirelli Gravel RC 45mm tires

Hubs / Headset / BB

Chris King Matte Jade

Cockpit & Seatpost

ENVE AR Bar
ENVE Stem

Mosaic GT-1 i45

Built for the Long Way Around

Some bikes are built to turn heads. Others are built to disappear beneath you, quietly doing their job mile after mile.This custom Mosaic GT-1 i45 was designed to do both.

Created through a collaboration between Alpha Bicycle Studio and Mosaic Cycles for the MADE Show in Portland, this one-off build represents the intersection of craftsmanship, performance, and purpose. Every component was selected with a clear objective: create a gravel machine capable of tackling the biggest endurance events in the world while showcasing what's possible when rider, builder, and studio collaborate from the ground up.

A Bike Designed Around Adventure

At first glance, the custom finish commands attention. The hand-painted camouflage-inspired pattern contrasts beautifully against the raw titanium frame, creating a look that feels equally at home on a show floor or a remote stretch of Flint Hills gravel.

But beneath the paint lies the real story.

The GT-1 i45 platform was developed by Mosaic to blur the lines between race bike and adventure bike. It offers the responsiveness and efficiency required for competitive gravel racing while maintaining the comfort and confidence needed for all-day efforts that stretch well beyond 100 miles.

For riders chasing events like Unbound Gravel, The Mid South, SBT GRVL, and countless self-supported adventures, that balance matters.

Built With Endurance in Mind

Endurance racing demands more than speed. It requires reliability, comfort, efficiency, and the ability to stay composed deep into a race when fatigue begins to accumulate.

This build was assembled with those demands in mind

Build Brands

Frame

Custom Mosaic GT-1 i45

Titanium remains one of the most sought-after frame materials for long-distance riding. Its unique ride quality helps smooth rough terrain while delivering the responsiveness expected from a modern performance gravel bike.

Drivetrain

Shimano GRX 12s · Wolf Tooth 42T Chainring · GRX 9-45T Cassette

The gearing strikes a balance between race-day speed and climbing capability, offering enough range for steep gravel sectors while maintaining efficient cadence on fast roads.

Wheels & Tires

Chris King 44 ARD · Pirelli Gravel RC 45mm tires · Chris King Matte Jade

Built for speed, durability, and comfort, the combination of deep-section ARD44 wheels and high-volume gravel tires delivers confidence across a wide range of terrain. Whether rolling over washboard roads or carving through fast descents, the setup prioritizes efficiency without sacrificing control.

Cockpit

ENVE AR Bar · ENVE Stem

A refined cockpit helps reduce fatigue over long hours in the saddle while maintaining precise handling when conditions become technical.

Customizations

A refined cockpit helps reduce fatigue over long hours in the saddle while maintaining precise handling when conditions become technical.

Racing this bike in brutal conditions in the 2026 Unbound 200 gave me the ability to have a 2.1 MTB tire on the suspension fork. I had zero mechanicals throughout the sub 14-hour effort. Looking forward to the next big ride.

R. Lee | Number5 Cycling Club

From Portland to Unbound

While this bike made its debut at the MADE Show, its future isn't intended to be spent hanging on a wall.The vision behind the build was always simple: create a machine worthy of the world's toughest gravel events.From 200-mile race days at Unbound Gravel to sunrise-to-sunset adventure rides, the GT-1 i45 is designed to reward riders who choose the long route home. It embodies the idea that performance and craftsmanship don't have to exist independently. The fastest bike isn't always the one with the most aggressive geometry or the lightest weight.Sometimes it's the bike that still feels great after ten hours of riding.

Built by Riders, For Riders

At Alpha Bicycle Studio, every custom build begins with a conversation. Riding style, goals, terrain, fit, and aesthetics all play a role in shaping the final product.

This Mosaic GT-1 i45 represents that philosophy at its highest level—a purpose-built gravel bike designed to perform on race day while remaining timeless enough to be ridden for years to come.Because the best bikes aren't built for the showroom.They're built for the next adventure.

Your best ride starts here

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