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 for UDH and T-Type compatibility. 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 |
GEOMETRY | SM | MD | LG | XL |
WEIGHT (NO SHOCK) | 5.7lbs 2.58kg | 5.7lbs / 2.58kg | 5.7lbs / 2.58kg | 5.7lbs / 2.58kg |
SIZING | 5'0-5'6" | 5'4"-5'10" | 5'8"-6'2" | 6'1"-6'6" |
REACH | 427mm | 456mm | 483mm | 507mm |
HEADTUBE ANGLE | 65.6° | 65.6° | 65.6° | 65.6° |
SEATTUBE ANGLE (Effective) | 77° | 77° | 77° | 77° |
WHEELBASE | 1188mm | 1217mm | 1247mm | 1279mm |
CHAINSTAY LENGTH | 440mm | 440mm | 440mm | 440mm |
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 ANGLE (Actual) | 73° | 73° | 73° | 73° |
SEATTUBE LENGTH | 405mm | 420mm | 440mm | 465mm |
MAX SEATPOST DEPTH | 255mm | 255mm | 280mm | 280mm |
LOWER HEADSET STACK HEIGHT | 12mm | 12mm | 12mm | 12mm |
FRONT CENTER | 749mm | 778mm | 808mm | 840mm |
*Based off a 584mm axle to crown, 44mm offset fork // **Based off tire OD of 750mm front and 709mm rear

JS TUNED TRAIL LINK

UDH & T-Type Compatibility

THREADED BB

INTERNAL CABLE ROUTING

EXTERNALLY MOUNTED TOP LINK
