At the heart of the JEFFSY 29 AL Base is a high-quality aluminum frame which is based on the JEFFSY MKI version. With its downhill-oriented geometry, low BB height and slack headangle it is one of the more aggressive all-mountain bikes on the market. As is the YT way, with the JEFFSY 29 AL Base you’ll ride faster and be more playful and creative on your bike. Setting up the bike is child’s play thanks to simple and reliable components that both beginners and experienced riders will enjoy.
With 140 mm of travel, the FOX 34 Float Rhythm fork and FOX Float DPS Performance shock are always ready to get rowdy while the low standover height, the generous reach and the compact chainstays ensure optimal handling. For a perfectly balanced bike, the chainstays of the XL and XXL frame sizes are longer. The result: JEFFSY lets you truly redefine your riding style.
Setting up the JEFFSY 29 AL Base is child’s play thanks to simple and easy-to-use components that both beginners and experienced riders will enjoy. The 140 mm FOX 34 Float Rhythm fork was developed for aggressive trails and provides plenty of travel for almost any terrain. The FOX Float DPS Performance shock transmits enough feedback from the ground to let you know what’s going on, while remaining both compliant and sensitive – 3 preset positions let you tune it to almost any conditions.
SRAM’s NX Eagle drive train is reliable and precise and with 11–50 teeth on the cassette you’ll always have enough gears to take on your next adventure. The 4-pot calipers of the SRAM T brakes were developed together with downhill riders for reliable braking performance, while the butter-smooth action of the SDG Tellis dropper post puts you in the right riding position both on the way up and down the hill.
FrameJEFFSY ALLOY 29"
hydro-formed aluminum frame, V4L Virtual 4-Link rear suspension, 148x12mm DT Swiss QR Thru axle, seat stay/chain stay protection
WheelsetDT Swiss M 1900 SPLINE
29“ x 30mm | 110x15mm | 148x12mm
HandlebarRace Face AEFFECT R 35
20mm Rise | 780mm
ColorCONCRETE GREY / BLACK MAGIC
CONCRETE GREY / BLACK MAGIC
DEEP BLUE / MAGNESIUM WHITE
Front TireMaxxis Minion DHR II
29" | 2.40
StemRace Face AEFFECT R 35
Travel front/rear140mm / 140mm
Rear TireMaxxis Minion DHR II
29" | 2.40
GripsODI Elite Motion
V2.1 | Lock On
Frame SizeS / M / L / XL / XXL
CranksetSRAM NX Eagle
175mm | 32T | DUB
Weight*13,9 kg / 30,6 lb
* Weight measured without pedals in frame size S. Due to manufacturing tolerances of the individual components the bike weight may differ +/- 5%
Rear DerailleurSRAM NX Eagle
31.6mm | 125mm / 150mm Drop
ForkFOX 34 Float Rhythm
29“ | 140mm | 15QRx110 | 44mm Rake
ShifterSRAM NX Eagle
SaddleSDG FLY MNT
YT Custom | White | Grey
ShockFOX Float DPS Performance
3pos | 200X57mm
CassetteSRAM PG-1230 Eagle
11-50T | 12-Speed
BrakesSRAM Guide T
ROTOR CENTERLINE | 200mm / 180mm
ChainSRAM GX Eagle
Bottom BracketSRAM DUB Pressfit
Pedalsincluded / inklusive
The included pedals were not made for demanding trails or racing. That is why we also offer you quality pedals at an attractive price in the shopping cart.
Tool KitIceToolz Set
Torque Wrench (3NM-10NM; 3-6mm, reset) | Shock Pump (330psi/20.6bar; pressure relief valve) | Allen Key | Anti-Slip Paste
For an even better ride feel, the new JEFFSY 29 has a significantly longer reach than its predecessor and on the CF Pro Race model we also gave it 10 mm more travel. The seat tube angle has been made steeper for a more ergonomic seated position, so that even taller riders end up in the center of the bike and can fully benefit from the slack headangle. To apply YT’s Tailor Made concept also to the new JEFFSY 29, we’ve significantly shortened the seat tube and introduced an XXL size. This gives you the choice between two or even three frame size in order to adapt the reach measurement to your riding style and preferences.
To ensure consistent handling across the frame sizes, we’ve made the chainstays longer on the XL and XXL. The now even slacker headangle has a calming effect on the bike and gives you more control when things get steeper and faster. This is also exactly the point where the longer reach makes itself known, helping JEFFSY stay on track and making sure even taller riders can sit “in” the bike. The integrated Flip Chip lets you further adapt the bike’s geometry to suit your technique and terrain. Run it in the low position to slacken the headangle and lower the BB for fast and rough terrain, or switch to the high position to raise the BB for better clearance and more fun on the climbs.
|A Toptube length||571 mm||592 mm||616 mm||637 mm|
|B Reach||405 mm||425 mm||445 mm||465 mm|
|C Stack||605 mm||610 mm||623 mm||628 mm|
|D Seattube length||400 mm||440 mm||480 mm||520 mm|
|E Chainstay length||435 mm||435 mm||440 mm||440 mm|
|F Headtube angle low/high||67 / 67,5 °||67 / 67,5 °||67 / 67,5 °||67 / 67,5 °|
|G Seattube angle (eff.) low/high||74,5 / 75 °||74,5 / 75 °||74,5 / 75 °||74,5 / 75 °|
|H BB Drop low/high||32/24 mm||32/24 mm||32/24 mm||32/24 mm|
|I Wheelbase||1132 mm||1154 mm||1178 mm||1205 mm|
|J Headtube length||90 mm||95 mm||110 mm||115 mm|