Primo
3T’s most versatile bike
PRIMO
CHOOSE YOUR BUILD
PRIMO APEX XPLR 1x12 700c
The world’s first full-aero gravel bike.
PRIMO GRX 1x12 700c
The world’s first full-aero gravel bike.
IT ALL STARTS WITH THE TIRES
To make the fastest possible bike, you need to start with the tires. Tire choice determines comfort & grip. But it also determines how you can shape the frame to redirect the airflow.
To aerodynamically engineer the frame around the tires, you need to know what their REAL measurements are. Not what’s on the label, but how they really fit. That’s REALFAST aerodynamics. But it’s not easy, as the tire dimension depends on the rim you use, the pressure and of course how accurate the manufacturer’s claimed size is.
So we took hundreds of measurements to learn the real tire widths (which we call WAM - Width As Measured and RAM - Radius As Measured) and use that to engineer the frame around accurate tire measurements.
The Primo is designed to fit road, cyclocross and gravel tires. In case adventure calls, wide 650b wheels can be used to maximize the bike’s capabilities and comfort.
Double check the maximum WAM and RAM of the Primo here.
REALFAST
Why is aerodynamics important on allroad (asphalt, gravel, fire roads, single track) rides?
- You may go slow off-road, but on the connecting asphalt sections you need road riding speed.
- If you’re slow because of gradients, aero doesn’t matter much. But if it's due to head- or crosswinds, you're slow relative to the ground but very fast relative to the air and that’s what determines the resistance you experience (that’s exactly why you’re slow).
- The Primo is also a great road bike in its own right. When using it for fast paved (group) rides, any aero benefit is appreciated.
We didn’t want the Primo to be fast in theory, but in the real world. So we tested at a realistic 20mph (32kmh) instead of the standard 30mph (48kmh) and optimized the frame for water bottles (tough to do long, epic rides without). We even designed the Sqaero shape to work well when covered in mud! The result? A muddy Primo with 40mm knobby gravel tires and 2 water bottles (red line in the graph) is faster than the equivalent clean round tube bike is with 28mm slick road tires and without bottles (grey line).
SQAERO
The key to the Primo’s speed is the aero downtube that is wide enough to catch the airflow coming off the big front tire (a skinny downtube wouldn’t even touch the airflow). But at 50mm wide, a full airfoil with a normal ratio would have to be 150-200mm deep, causing too much surface drag. So we square off the tail, keeping most of the aero performance with a 50x75mm cross section that is also close to perfect for strength and stiffness; our Sqaero shape. The wide downtube also help shielding the water bottles.
Sqaero tube shapes are also found on the headtube, seattube, seatstays, seatpost and fork to maximize the REALFAST concepts across the platform.
PRIMO versus RACEMAX, EXTREMA and ULTRA
The RaceMax, Ultra and Extrema all have gravel-specific geometry. Our RaceMax has been developed to be the best on fast gravel, where speeds are highest. The Extrema excels on fast adventures and gravel’s roughest races, while Ultra combines tire clearance with aerodynamics optimized to handle the toughest terrain.
The Primo frame features road inspired geometry, while still allowing for excellent wheel and tire versatility. Ride your faster days with 700c tires then swap to 650b when adventure calls. The Primo, your perfect all-round bike.
design in details
HANG LOOSE HANGER:
Mounting a rear wheel with disc brake can be a pain, we make it easy. Forget the derailleur, focus on the disc, put the wheel in, slide thru the axle and hang the derailleur back with the wheel already securely in place.
CLEAN PERFORMANCE:
Internal cables, hoses and seatpost clamp clean up the frame aerodynamically and visually. Dedicated FlipTop cable guides are future-proof with in mechanical & electronic versions for single & double chainrings.
FRAME SPECIFICATIONS
For frame specifications, component compatibility, clearances, etc, please check our PRIMO FRAME SPECIFICATIONS. Geometry information is found below
GEOMETRIES
| Size | S | M | L | XL |
|---|---|---|---|---|
| Rider Height (cm) | 157-170 | 168-180 | 178-191 | 188-201 |
| Rider Height* (inches) | 5'2"-5'7" | 5'6"-5'11" | 5'10"-6'3" | 6'2"-6'7" |
| Max. BB to saddle rail** (mm) | 763 | 790 | 818 | 845 |
| Stack | 517 | 546 | 575 | 604 |
| Reach | 366 | 378 | 390 | 402 |
| Headtube angle | 69.5 | 71.1 | 72.5 | 72.5 |
| Fork rake | 50 | 50 | 50 | 50 |
| Fork axle-crown | 395 | 395 | 395 | 395 |
| Front center | 591 | 598 | 606 | 627 |
| Rear center | 415 | 415 | 415 | 415 |
| BB drop | 70 | 70 | 70 | 70 |
| Headtube length | 101 | 125 | 150 | 180 |
| Toptube length | 529 | 550 | 571 | 592 |
| Seattube length | 463 | 490 | 518 | 545 |
| Seattube angle | 72.5 | 72.5 | 72.5 | 72.5 |