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YT Industries Jeffsy 29 Core 1 AL

Last known price
$2,999
Travel
150 / 145 mm Fork / rear shock
Wheels
29″
Drivetrain
12
Weight
16.5 kg 36.4 lb · Reference configuration not specified
Frame
Aluminum
Brakes
Hydraulic disc

Rider height by size (cm)

Size guide
  • SM Low 153–166
  • SM High 153–166
  • MD Low 162–176
  • MD High 162–176
  • LG Low 172–185
  • LG High 172–185
  • XL High 181–194
  • XL Low 181–194
  • XXL High 190–203
  • XXL Low 190–203

Components

16 of 16 identified

Parts found in a manufacturer catalog show their brand, model and key numbers, and the steps show how precisely they are identified: brand, series, model, or the exact product. The info button has every detail and the text the manufacturer published.

Suspension

2 parts

Drivetrain

5 parts
  • Bottom bracket BB-MT501
  • Cassette CS-M6100
  • Crankset FC-M512
  • Rear derailleur RD-M6100
  • Shifters SL-M6100

Sizes and geometry

Size explorer

Enter your height to highlight matching ranges.

Size LG Low

Table
Reach 481mm
Stack 622mm
Wheelbase 1236mm
Head angle 65.6°
Seat angle 78.5°
Every size is drawn to the same scale, in millimeters. Explanatory schematic on an assumed 29″ wheel; exact published values are in the table below.
Size Reported by the manufacturer

Specifications

Frame and fork

Intended fit
  • Unisex
Frame material
  • Aluminum
Bicycle weight
  • 16.5 kg
  • 36.4 lb

Suspension

Suspension configuration
  • Full suspension
Front travel
  • 150 mm
Rear travel
  • 145 mm

Drivetrain

Rear sprockets
  • 12
Derived by Bikelake

Technical analysis

2 measures

How these figures sit among bicycles of the same class and model year. Context, not a ranking.

Front travel

150 mm

This value is above the central range for this class.

Cohort
Mountain / Trail Model year: 2026
Sample
1,640 bicycles with this information
Coverage
96.3% of the class

Shifting

Mechanical

388 of 1,702 bicycles with this information use electronic shifting.

Cohort
Mountain / Trail Model year: 2026
Sample
1,702 bicycles with this information
Coverage
100.0% of the class

Lineup changes

The published facts that differ across this family's builds and from the same model a year earlier. Missing information never counts as zero.

Differences across 2026 builds

Differences across 2026 builds
Specification This bicycle YT Industries Jeffsy 29 Core 1 AL YT Industries Jeffsy 29 Core 2 AL YT Industries Jeffsy 29 Core 2 CF YT Industries Jeffsy 29 Core 3 AL YT Industries Jeffsy 29 Core 3 CF YT Industries Jeffsy 29 Core 4 CF
Frame
Frame material Aluminum Aluminum Carbon Aluminum Carbon Carbon
Bicycle weight 16.5 kg 15.8 kg 15.1 kg 15.8 kg 15.8 kg 14.6 kg
Drivetrain
Rear sprockets 12 Not informed Not informed 10 10 12
Front chainrings Not informed Not informed Not informed 1 1 1
Cockpit
Seatpost Rigid seatpost Dropper seatpost Dropper seatpost Dropper seatpost Dropper seatpost Dropper seatpost
Shifting Mechanical Mechanical Mechanical Electronic Electronic Electronic
Derailleur hanger Not informed Not informed Not informed Not informed Not informed UDH
Other specifications
Wheel material Aluminum Aluminum Aluminum Aluminum Aluminum Carbon
Bottom bracket standard Not informed Not informed Not informed BSA Not informed Not informed

Other models in this family

8 models

Published versions from the same family and model year.

YT Industries Jeffsy 29 Core 1 AL, by YT Industries

This bicycle

Trail

Jeffsy 29 Core 1 AL

  • Weight: 16.5 kg
  • Suspension: 150/145 mm
  • Wheel size: 29″
YT Industries Jeffsy Primus 24 AL, by YT Industries

Mountain youth

Jeffsy Primus 24 AL

Youth / Mountain youth

  • Weight: 12.6 kg
  • Suspension: 130 mm
  • Wheel size: 24″
YT Industries Jeffsy Primus 26 AL, by YT Industries

Mountain youth

Jeffsy Primus 26 AL

Youth / Mountain youth

  • Weight: 14.0 kg
  • Suspension: 140 mm
  • Wheel size: 26″

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