2024 YT Industries
Jeffsy CORE 1 29
A 29″ aluminum frame full suspension trail bike with high-end components.
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Manufacturer Price
$1,999| Weight | 35.3 lbs |
|---|---|
| Frame | Aluminum |
| Suspension | Full, 145 / 150mm |
| Fork | RockShox Lyrik |
| Shock | RockShox Deluxe Select+ |
| Wheels | 29″ Aluminum |
| Drivetrain | 1 × 12 |
| Groupset | NX Eagle, Truvativ Descendant |
| Brakes | Hydraulic Disc |
| Seatpost | Dropper |
For This Bike
Based on build material and quality level of the frame, fork, wheelset, groupset, suspension system, and more.
Compare the full Jeffsy model range
View Comparison5'0" – 5'6"
5'3" – 5'10"
5'7" – 6'1"
5'11" – 6'5"
6'2" – 6'8"
None yet.
Do you have this bike? Help other riders make a decision about which size will work for them by sharing your own size and fit notes.
Mar 2024 · Ben Haworth
The YT Jeffsy Core 4 is a bike that arrives in a box that is not quite perfect out of the box. BUT... there is loads of potential here.
Jan 2024 · Simon Kohler
How did the YT JEFFSY CORE 5 fare in our big 2024 trail bike group test?
Trail bike with fun guarantee
Mind-boggling price/performance ratio
Super intuitive handling
Pure agility!
Countless clever frame details
No storage compartment on the alloy model
Jan 2024 · Dario DiGiulio
The Jeffsy boasts easy, intuitive handling, and now has in-frame snack storage.
Intuitive and easy handling
Active, grippy suspension feel
Quality frame with well-executed storage and accessories
Requires attention in very rough terrain
Some may wish for more supportive suspension
Stock frame storage bags could be improved
Nov 2023
Review: All-new YT Jeffsy reminds us that trail bikes are what we all love about mountain biking, from singletrack to bikeparks…
Oct 2023 · Jamie Darlow
YT has reworked its Jeffsy trail bike, adding more tech, more price, and better performance
Pedals better when sat down and stood up cranking
Frame is sleeker and now comes with internal storage
Bikes range from £2,500 up to £5,999 for Core 5
Amazing spec on Core 5, with Fox Factory suspension
Costs a bomb for a direct-sales bike
Frame storage door could be bigger
Aug 2022
The YT Jeffsy 29 Core 3 is a very capable all-mountain bike which can handle the rough stuff but is equally at home on flow trails and jumps. While the specification list is solid for the money, it's worth paying extra attention to frame sizing and geometry to get the ride you want. With a longer dropper and some tougher tyres this bike has what it takes to be a real challenger when it comes to the best mountain bikes.
May 2022 · Ed Thomsett
An excellent complete package that makes fun of all but the gnarliest descents, thanks to a head angle that feels too steep
Predictable ride quality
A solid suite of parts
Great for riding just about any terrain
Conservative head angle
A good price, but the outrageous value YT’s reputation was built on isn’t there
Dec 2021 · Lydia Tanner
A great value with an appetite for rowdier trails. .
Incredibly capable
Incredibly fun
Incredibly versatile
Incredible value
Pedal bob had us using the lockout on long climbs
Slightly limited water bottle space
Could use stronger brakes
| Fork | ROCKSHOX LYRIK BASE, 150 mm Travel | Rush RC | 110 x 15 mm Axle | Offset 44 mm Travel: 150mm Spring Type: Air |
|---|---|
| Shock | ROCKSHOX DLX SELECT+, Shock Length: 210 mm | Shock Stroke: 55 mm | 145 mm Travel | RT | 0L1 Volume Reducer Travel: 145mm Spring Type: Air |
| Bottom Bracket | SRAM DUB BSA, BB DUB BSA 73 MTB |
| Headset | ACROS AZX-576, ZS44 ZS56 | High Cap | 2 Spacer 5mm |
| Stem | E13 BASE 35, Length 50mm | 35mm Clamp | Rise 0° | 6061 AL |
| Handlebar | E13 BASE 35, Width 780mm | Rise 35mm | 9° Back Sweep | 5° Up Sweep | 6061 AL |
| Saddle | SDG BEL AIR 3.0, YT Custom | Width 140 mm I Lux-Alloy Rail |
| Seatpost | YT POSTMAN V2, Ø 31,6mmI MMX-Remote | Adjustable drop 20/10/5mm | 125 mm (S) I 150 mm (M) | 170 mm (L) | 200 mm (XL) | 230mm (XXL) Type: Dropper |
| Grips | ODI ELITE MOTION V2.1, Lock On |
| Rear Derailleur | SRAM NX EAGLE, 12-speed |
|---|---|
| Crank | SRAM DESCENDANT 6K EAGLE DUB, Crank Arm Length 170 mm | 32T |
| Shifters | SRAM NX EAGLE, 12-speed |
| Cassette | SRAM PG-1210 Eagle, 11-50T | 12-speed |
| Brakes | SRAM DB8, Maxima Mineral Oil | Rotor CENTERLINE | Front 200 mm / Rear 200 mm Type: Hydraulic Disc |
| Rims | SUNRINGLE SR329 TRAIL COMP, Front: Aluminum Rims 29“ | Inner Width 30 mm | Hub 110 x 15 mm |, Rear: Aluminum Rims 29“ | Inner Width 30 mm | Hub 148 x 12 mm | Freehub HG |
|---|---|
| Tires | FRONT: MAXXIS DHF I REAR: MAXXIS MINION DHR II, Front: Tire Size 29“ x 2,50 I EXO+ Casing I 3C MaxxTerra Compound I Tubeless Ready I, Rear: Tire Size 29“ x 2,40 I EXO+ Casing I 3C MaxxTerra Compound I Tubeless Ready |
Last updated May 2