We’ve reimagined our classic Primer to deliver the ultimate trail bike for 2025. Striking the perfect balance between stiffness and compliance is a craft we’ve mastered, optimizing the carbon lay-up to increase lateral stiffness around the bottom bracket while maintaining vertical compliance for a smoother, more controlled ride. The updated geometry features a steeper seat tube angle and longer reach, aligning with modern trail standards. We’ve also enhanced the rear triangle, which now comes standard with UDH that is T-Type compatibile. To complete the package, we partnered with FOX and Rockshox to custom-tune the rear shock, ensuring seamless integration with our JS Tuned Suspension Design. Paired with 150mm front travel and 150mm rear, the Primer is ready to tackle any trail with confidence and precision.
| BUILD | PRIMER 29 FRAME |
| FRAME | Full carbon fiber front and rear triangle utilizing an optimized carbon layup for the trail category. Features fully-guided internal cable routing, alloy top link with integrated flip chips to adjust geometry, titanium hardware, ISCG-05 tabs, and a threaded bottom bracket. Universal derailleur hanger (UDH) and quick-release rear axle( 148mm Boost hub spacing) |
| ROCKSHOX SUPER DELUXE ULTIMATE |
ROCKSHOX Deluxe Ultimate RC2T, 150mm, 210x50mm, 20x8 front/rear hardware |
| FOX FACTORY FLOAT X | FOX Flat X Factory,150mm, 210x50mm, 20x8 front/rear hardware |
| ROCKSHOX LYRIK ULTIMATE |
RockShox Lyrik Ultimate RC2, 150mm, 44mm offset, Charger 3 damper, DebonAir+, Boost 15x110mm |
| YEAR | 2026 |
| CATEGORY | Trail |
| AVAILABLE SIZES | S, M, L, XL |
| MAX FRONT TRAVEL | 150mm |
| MAX REAR TRAVEL | 150mm |
| HEADSET | ZS44 Upper/ EC49 Lower |
| SEATTUBE DIAMETER | 31.6mm |
| SEATPOST CLAMP | 36.1mm (Intense Collar Only) |
| MAX SEATPOST INSERTION DEPTH | (S)255mm (M)255mm (L)280mm (XL)280mm |
| BB SHELL WIDTH | BSA 73mm |
| MAX CHAINRING | 34T |
| CHAINLINE | 52mm Shimano 12S 52mm SRAM Eagle 12S 55mm SRAM T-Type 12S |
| RECOMMENDED MAX TIRE WIDTH | 2.5" |
| BRAKES | Disc Brake Hydraulic, Post Mount/Direct |
| MIN BRAKE ROTOR SIZE | 180mm |
| MAX BRAKE ROTOR SIZE | 203mm (with adapter) |
| DERAILLEUR HANGER | UDH |
| T-TYPE COMPATIBLE | Yes |
| REAR HUB SPACING | 148mm x 12mm through Axle Boost |
| SHOCK SIZE | 210mm x 55mm |
| FRONT SHOCK MOUNT HARDWARE | 8mm x 20mm |
| REAR SHOCK MOUNT HARDWARE | 8mm x 20mm |

| FRAME SIZE | SM | MD | LG | XL |
| REACH | 427mm | 456mm | 483mm | 507mm |
| HEADTUBE ANGLE | 65.6° | 65.6° | 65.6° | 65.6° |
| SEATTUBE ANGLE (EFFECTIVE) | 77° | 77° | 77° | 77° |
| SEATTUBE ANGLE (ACTUAL) |
73° |
73° |
73° |
73° |
| WHEELBASE | 1188mm | 1217mm | 1247mm | 1279mm |
| CHAINSTAY LENGTH | 440mm | 440mm | 440mm | 440mm |
| FRONT CENTER | 749mm | 778mm | 808mm | 840mm |
| BB HEIGHT | 344mm | 344mm | 344mm | 344mm |
| STACK | 568mm | 597mm | 626mm | 656mm |
| TOPTUBE LENGTH | 618mm | 618mm | 627mm | 645mm |
| HEADTUBE LENGTH | 90mm | 90mm | 100mm | 120mm |
| BB DROP | 31mm | 31mm | 31mm | 31mm |
| SEATTUBE LENGTH | 405mm | 420mm | 440mm | 465mm |
| MAX SEATPOST INSERTION DEPTH | 255mm | 255mm | 280mm | 280mm |
| WEIGHT (NO SHOCK) | 5lbs 10oz / 2.55kg | 5lbs 13oz / 2.63kg | 6lbs / 2.72kg | 6lbs 3oz / 2.80kg |
*Based off a 565mm axle to crown, 44mm offset fork // **Based off tire OD of 750mm

JS TUNED TRAIL LINK
UDH & T-Type Compatibility
THREADED BB
INTERNAL CABLE ROUTING
EXTERNALLY MOUNTED TOP LINK