YT JEFFSY

93/100
BikeRide Score
?
Scores
See all scores
Users (19 ratings)
96
Experts (5 reviews)
86
YT JEFFSY
Where to buy
$2,789.10 Jenson USA See it
View all prices Show fewer prices
See at Jenson USA
We earn affiliate commission. Learn more
Bike Size Charts

BikeRide finds and shows you the best prices of the bikes you want to buy. Prices constantly change and it’s impossible to compare them all yourself.

We search for prices on over 120 bike retailers to guarantee that we find the lowest prices – to save you time and money.

It’s a promise we stand behind: If you find a lower price on a bike elsewhere, we will sell it to you for 10% less. For example, if you find a bike for $480 that we have listed at $500, we will offer you to buy it for $432 through BikeRide. The bike must be the same color and size, sold in the US and not include the use of a coupon.

If you find a lower price, email us at [email protected] with documentation of the price. We’re committed to making sure that the cost of a bike does not keep you from cycling!

Facts

Gender
Men, Women
Type
Mountain, Trail, Non-Electric
Release Year
2023
Brand
YT
Wheel Size
29”
Number of Gears
12 (1x12)
Gearing Type
External Derailleur
Weight
32.18, 34.61, 36.37 lb
Suspension
Full
Brake Type
Disc: Hydraulic
Frame Material
Carbon Fiber, Aluminum

Summary of Reviews

We have read all expert and user reviews on the YT JEFFSY. In summary, this is what cyclists think.

15 reasons to buy

  • The JEFFSY CORE comes in six builds, three aluminum and three carbon.
  • Reviewers say the all-rounder JEFFSY is a joy to ride on everything from mellow trails to enduro tracks.
  • Experts praise the active rear suspension for providing excellent traction, smoothing out trail chatter, and isolating bigger hits for a plush feel.
  • Several testers highlight the bike's composure and stability at speed.
  • The JEFFSY's balanced geometry inspires confidence on technical descents.
  • Testers say the JEFFSY corners well.
  • Reviewers are encouraged to choose playful lines thanks to the agile and responsive handling.
  • Reviewers find the seated climbing position ideal for putting down power.
  • The JEFFSY has a geometry flip-chip, and most testers prefer the stock low setting.
  • Reviewers say the provided resources make assembly and suspension setup easy.
  • All builds fit a 20oz water bottle and a tool mount under the top tube. The carbon frame also has internal storage.
  • Testers appreciate the tunability of the CORE 3's RockShox Ultimate suspension components.
  • Reviewers praise the CORE 3’s compliant Crankbrothers Synthesis Enduro alloy wheels.
  • A tester relishes the power of the Hayes Dominion A4 brakes (CORE 2, 3, 4).
  • The CORE 2's smooth and active FOX Float Performance suspension impresses reviewers.

5 reasons not to buy

  • Reviewers who size up due to the short reach recommend choosing size based on geometry.
  • Two testers say the short chainstays mean the rider’s weight sits too far back on steep climbs.
  • Testers of sizes Large and smaller are disappointed by the meager dropper travel.
  • The JEFFSY is two to four pounds heavier than trail bikes with similar travel.
  • Some testers find it hard to reach the water bottle under the shock.

Bottom line

The YT JEFFSY is marketed as an all-mountain bike, and reviewers agree, saying it's enjoyable to ride on everything from mellow tracks to enduro descents, showcasing its capabilities as an all-rounder. Experts relish the intuitive ride that immediately feels comfortable thanks to the balanced geometry and dialed suspension. In testing, the suspension provides ample traction on climbs and eats up obstacles on the way down, exceeding expectations for its travel. The weight is high, but the burly components seem worth the weight penalty. Overall, the JEFFSY comes highly recommended for its impressive price, specifications, and performance.

Expert Reviews

86/100 based on 5 rated expert reviews
Apply to become an expert
90
Mountain Bike Rider
Level 5 expert

I’ve Tested Trail Bikes for 20 Years, and While Performance Has Never Been Better There Can Only Be One Winner of Our 2025 Trail Bike of the Year Award…

Level 5 expert

I felt really confident. I felt I could do everything I want to do when I go mountain biking on this bike with less effort, and I love that.

Visit full review
80
off-road.cc
Level 5 expert

YT Industries JEFFSY MK3 CORE 4 Mountain Bike Review

Level 5 expert

As an all-mountain bike, the JEFFSY remains a capable climber thanks to a neutral seated position, although the shorter chainstays do hamper this a little. With top-tier suspension and powerful brakes, the JEFFSY comes alive on the descents…

Visit full review
90
BikeRadar
Level 5 expert

YT JEFFSY CORE 1 Review

Level 5 expert

While it isn’t the lightest, it impressed me with its efficient climbing performance, offering a neutral pedalling platform and plenty of grip… On the descents, it shines with its supple yet supportive suspension that punches above its 145mm travel figure.

Visit full review
90
Bike Perfect
Level 5 expert

YT JEFFSY CORE 4 Review – MK3 Version of the Excellent All-Mountain Bike

Level 5 expert

The new JEFFSY is an excellent trail bike package that can handle tougher stuff too. Improved pedaling has made it a true all-mountain bike that I had a blast riding on a wide range of trails.

Visit full review
80
BikeRadar
Level 5 expert

YT JEFFSY CORE 3 Review | Trail Bike of the Year Contender

Level 5 expert

Up hills, it blends grip-giving suppleness with efficiency, ensuring you aren’t spinning out, nor wasting watts. Downhill, the bike is capable on a broad range of tracks, from fast and flowy to much more chunky.

Visit full review
Pinkbike
Level 5 expert

Field Test: YT JEFFSY CORE 1 – Where Value Meets Performance

Level 5 expert

The weight is hard to ignore, but so is the performance that extra burden brings you. For riders that want an aggressive trail bike to do everything, especially in the value category, the JEFFSY is a very strong contender.

Visit full review
The Loam Wolf
Level 5 expert

YT Industries JEFFSY CORE 4 Review

Level 5 expert

… for an all day, do-it-all ripper, I think the JEFFSY’s finishing touches, spec and price push it towards the top end of the trail bike category, with most other brands struggling to equal such desirable features at this price point.

Visit full review
Loading…
Mo and Hannah Awesome MTB
Level 4 expert

YT JEFFSY First Ride Impressions! (Climbs Okay, Descends Great!)

Level 4 expert

I think in the case of the YT JEFFSY, you have a bike that descends amazingly and is very affordably priced. Is it the best climber? On smoother, fire road climbs, probably not with an open shock.

Visit full review
Pinkbike
Level 5 expert

Review YT JEFFSY CORE 4

Level 5 expert

Overall, I found the YT JEFFSY a great bike for people looking for easy and intuitive handling, an unfussy layout, and good ride feel regardless of whether you’re keeping it chill or pushing your limits.

Visit full review
Mountain Bike Action
Level 5 expert

YT JEFFSY Long Term Review – All Mountain, All Value

Level 5 expert

The JEFFSY is a much more well-rounded bike than the shred-it-style advertising footage would have you believe. It feels more nimble than an enduro race bike and more burly than many trail bikes.

Visit full review
ENDURO Mountainbike Magazine
Level 5 expert

YT JEFFSY CORE 5 – In Our Big 2025 Trail Bike Comparison Test

Level 5 expert

Even in 2025, the JEFFSY remains a top-tier trail bike with no real weaknesses. It rides similarly to the test-winning Stumpjumper, though not quite as agile, and encourages fast, playful trail sessions.

Visit full review
The Radavist
Level 5 expert

Big. Budget: A 2024 YT JEFFSY CORE 2 Review

Level 5 expert

That’s what I think is most remarkable about the JEFFSY package. All of its attributes perfectly reflect the platform’s versatility, even down to the component spec.

Visit full review
Wideopen
Level 3 expert

Long Term Review: Pete’s YT JEFFSY CORE 4.

Level 3 expert

In general though, the YT JEFFSY CORE 4 is ready to take you wherever you want to go, at speed and with a confidence-inspiring feel that just keeps coming.

Visit full review
Singletrack
Level 5 expert

YT JEFFSY CORE 4 Review

Level 5 expert

The YT JEFFSY CORE 4 is a bike that arrives in a box that is not quite perfect… But… there is loads of potential with this beguiling bicycle.

Visit full review
bike-test.com | ride better bikes / eMTB-test.com
Level 5 expert

The New YT JEFFSY in Review [German Video]

Level 5 expert

The JEFFSY climbs everywhere, but with [34.17lb], it’s no rocket on the way up. You’ve got to be honest about that. However, going downhill, it totally delivers. Geometry, suspension, and spec come together to create a real powerhouse.

Visit full review
Apply to become an expert

User Ratings

96/100 based on 19 ratings
  • 5 star
    95%
  • 4 star
    0%
  • 3 star
    0%
  • 2 star
    0%
  • 1 star
    5%

Rankings

Compared to other bikes
#25 Best Mountain Bike
Top 20%
#14 Best Trail Bike
Top 20%
#109 Best of All Bikes
Top 20%

Best Mountain Bikes

Mountain bikes with the highest BikeRide Scores
?
See all mountain bikes

Bike Comparison

YT JEFFSY in comparison to averages
YT JEFFSY
93
Average All Bikes
84
Average YT Bike
93
Average Mountain Bike
87

Forum Discussions

Discuss which bike to choose in the forum
See all forum topics