YT Jeffsy 29 CORE 4

YT Jeffsy 29 CORE 4

Product information


Available color
Spec Score
Price Value


The Jeffsy 29 CORE 4 bike, manufactured by YT, is designed for high performance on demanding terrain. It has a FOX Float DPX2 Factory shock and FOX 36 Float Factory fork with 150mm travel for both the front and rear of the bike. It has a SRAM X01 Eagle shifter and rear derailleur, SRAM G2 RSC brakes, and DT Swiss XM 1700 Spline wheels. The bike's Renthal Fatbar 35 handlebar is optimised for performance with 780mm length, 30mm rise, 5° up, and 7° back. The Maxxis Minion DHR II front tire has a tubeless-ready, 3C MaxxGrip compound with an EXO casing. The bike's weight is considered favourable within its class.


  • premium_carbon_frame
  • top_rim
  • good_weight
  • top_groupset
  • premium_suspension
  • top_reviews

Show Bike on


srp4999 €
travel_front150 mm
travel_rear150 mm
weight13.9 kg
wheels29 Aluminum
groupsetSram X01 EAGLE
forkFox 36 Factory
shockFox Float DPX
brakesSram G2

Video Reviews



Ed Thomsett

An excellent complete package that makes fun of all but the gnarliest descents, thanks to a head angle that feels too steep

  1. Predictable ride quality; a solid suite of parts; great for riding just about any terrain
  1. Conservative head angle; a good price, but the outrageous value YT’s reputation was built on isn’t there


Matt Beer

Following the recent release of YT's Capra and Decoy MX Uncaged 9 builds is the trail-friendly 150mm Jeffsy Uncaged 8.


Alan Muldoon

Whether you’re 5ft 1in or 6ft 4in tall, you won’t have any issues achieving a glove-like fit on the YT Industries Jeffsy Core 2.

  1. Great suspension & handling
  1. Pricey given the spec

Loam Wolf

Sean Leicht

The YT Jeffsy 29 Core 4 is a versatile all mountain bike that’ll happily crunch out mellower miles or tackle some tough enduro tracks.

Vital MTB


Vital Durability Review - YT Jeffsy Core 3 Not your typical Vital bike test...

  1. All fun, all the time
  2. Capable climber
  3. Excellent parts spec
  4. Encourages aggressive riding
  5. Confident descender for both rocks and jumps
  6. A true all-rounder
  1. Frame protection quickly peels
  2. Seemingly forever sold-out (even before the bike boom)

Outdoor Gear Lab

The Jeffsy Core 3 is the latest version of YT's popular longer travel trail bike. While other brands have gone to extremes with their geometry, this bike's moderate numbers are the primary reason it is such a well-rounded, versatile, and user-friendly...

  1. Great build for the price
  2. Well-rounded performance
  3. Excellent value
  4. Composed and confident descender
  5. Super quiet
  1. A little heavy
  2. Not the fastest climber
  3. Geometry feels a touch dated
  4. Limited water bottle space

Community Reviews

0 out of 5 (no reviews yet)

Be the first, and share your expericence with this bike!

Write Review

Bikes from this Series



Frame Sizes
S, M, L, XL, XXL
Frame Colors
Black MagicVlad Red


FOX 36 FLOAT FACTORY (29“ | 150 mm Travel | Grip 2 | 110 x 15 mm Axle | 44 mm Offset)
Rear Shock
FOX FLOAT DPX2 FACTORY (Shock Length: 210 mm | Shock Stroke: 55 mm ≙ 150 mm Travel | 3pos-Adjust)


RENTHAL APEX 35 (50 mm |+/-6° | Black/ Gold)
RENTHAL FATBAR 35 (780mm | 30mm Rise | 7° Back | 5° Up | Custom Black)
SDG BEL AIR 3.0 (YT Custom | Width 140 mm)


Rear Derailleur
SRAM X01 EAGLE (12-speed)
Shift Levers
SRAM X01 EAGLE (12-speed)
SRAM XG1295 EAGLE (10-52T | 12-speed)
SRAM Descendant Carbon (Crank Arm Length 175 mm | 32T I DUB-PressFit)


Front Brake
SRAM G2 RSC (Rotor CENTERLINE Ø front 200 mm / rear 200 mm | Adjustable Bite Point and Reach)
Shift Levers


Front Rim
DT SWISS XM 1700 SPLINE (Aluminum Rims 29“ | Inner Width 30 mm | Front Hub 110 x 15 mm | Rear Hub 148 x 12 mm I XD I Ratchet 36SL)
Rear Rim
Front Tyre
DT SWISS XM 1700 SPLINE (Aluminum Rims 29“ | Inner Width 30 mm | Front Hub 110 x 15 mm | Rear Hub 148 x 12 mm I XD I Ratchet 36SL)

Geometry YT Jeffsy 29 CORE 4

seat_tube_length (mm)400 mm415 mm435 mm460 mm485 mm
seat_tube_angle77° / 77,5°77° / 77,5°77° / 77,5°77° / 77,5°77° / 77,5°
head_tube_length (mm)100105110120125
head_tube_angle66° / 66,5°66° / 66,5°66° / 66,5°66° / 66,5°66° / 66,5°
top_tube_length (mm)572 mm593 mm615 mm638 mm660 mm
chainstay_length (mm)435435435440440
wheel_base (mm)11741196121812471269
standover (mm)706 mm702 mm701 mm693 mm694 mm
stack (mm)618 mm622 mm627 mm636 mm640 mm
reach (mm)430 mm450 mm470 mm490 mm510 mm
bb_offset (mm)32 / 24 mm32 / 24 mm32 / 24 mm32 / 24 mm32 / 24 mm

Customer questions & answers

FAQ YT Jeffsy 29 CORE 4

Where to buy a YT Jeffsy 29 CORE 4

The Jeffsy 29 CORE 4 may be purchased directly from YT

How heavy is the Bike?

The Jeffsy 29 CORE 4 weights 13,90 kg. Thats roughly 30,6 pounds

What material is the frame of the YT Jeffsy 29 CORE 4?

The YT Jeffsy 29 CORE 4 ist crafted with Carbon

What is the recommended price given by the manufacturer YT?

The SRP Price is our information at 4999 EUR