Muddymoles mountain biking in the Surrey Hills and Mole Valley

YT Jeffsy 29 AL – 2017 specification and geometry

Posted by Matt | January 5, 2019 | 2 comments so far

YT Jeffsy 29 AL 2017 front view
As an aide memoire before the information disappears off the internet, this is the original specification of the Jeffsy 29er AL from 2017.

YT Jeffsy 29 AL spec 2017

Colour Black Pearl/Blue Lagoon
Frame Air-formed aluminium frame
V4L Virtual 4-Link rear suspension, 12x148mm, DT Swiss QR Thru axle
Fork RockShox Pike RC
Solo air, RC damper cartridge, Compression to ‘Lock’, Rebound, Tapered steerer, 15x100mm QR Thru axle, 140mm travel
Rear shock RockShox Monarch R
Debonair air-can, external rebound, 7.875″x2.25″/ 200x57mm
Wheelset DT Swiss M1900 Spline 29″
FW 15x100mm Thru Axle,
RW 12x148mm Thru Axle
Shifters Shimano SLX M670
2×10 speed
Rear derailleur Shimano M675
10 speed Shadow Plus
Front derailleur Shimano SLX M677
E-type, side swing, front pull
Cassette Shimano SLX
10 speed 11-36
Chain Shimano
Chainset Race Face Aeffect
175mm 24/36, BB92
Bottom Bracket Race Face
Brakes Shimano SLX M675
2 piston, tool-free reach adjust, metal pad w/fin
Discs Shimano SLX
200mm front/180mm rear
Seatpost RockShox Reverb Stealth internal cable routing
S: 390 mm/125 mm travel,
M , L, XL: 440mm / 150mm travel,
31.6 mm
Saddle SDG Circuit
Cro-Mo rails, 280mm x 135mm
Headset Acros AZX-203
ZS44;28.6 | ZS56;40
Stem Race Face Aeffect
35mm clamp,
S, M: 50mm,
L, XL: 60mm
Handlebar Race Face Aeffect
760mm, 20mm Rise, 8° backsweep, 5° upsweep, 35mm clamp
Grips Race Face
Love Handle
Tyres Onza Ibex
29×2.4″, 55a, FRC 120
Weight 14.3 Kg / 31.5 Lb

YT Jeffsy 29 AL 2017 side view

YT Jeffsy 29 geometry chart

 YT Jeffsy 29 AL 2017 geometry chart

Sizes S M L XL
A Toptube length Size S571 mm Size M592 mm Size L616 mm Size XL637 mm
B Reach Size S405 mm Size M425 mm Size L445 mm Size XL465 mm
C Stack Size S605 mm Size M610 mm Size L623 mm Size XL628 mm
D Seattube length Size S400 mm Size M440 mm Size L480 mm Size XL520 mm
E Chainstay length Size S435 mm Size M435 mm Size L440 mm Size XL440 mm
F Headtube angle low/high Size S66.9 / 67.6 ° Size M66.9 / 67.6 ° Size L66.9 / 67.6 ° Size XL66.9 / 67.6 °
G Seattube angle (eff.) low/high Size S74.7 / 75.3 ° Size M74.7 / 75.3 ° Size L74.7 / 75.3 ° Size XL74.7 / 75.3 °
H BB Drop low/high Size S32/24 mm Size M32/24 mm Size L32/24 mm Size XL32/24 mm
I Wheelbase Size S1132 mm Size M1154 mm Size L1178 mm Size XL1205 mm
J Headtube length Size S90 mm Size M95 mm Size L110 mm Size XL115 mm
K Steerer tube length Size S551 mm Size M551 mm Size L551 mm Size XL551 mm
L Fork offset Size S46 mm Size M46 mm Size L46 mm Size XL46 mm

Filed under Bikes in January 2019


About the author

Matt is one of the founding Molefathers of the Muddymoles, and is the designer and main administrator of the website.

Having ridden a 2007 Orange Five for many years then a 2016 YT Industries Jeffsy 29er, he now rocks a Bird Aether 9 and a Pace RC-627.

An early On-One Inbred still lurks in the back of the stable as a reminder of how things have moved on. You can even find him on road bikes - currently a 2019 Cannondale Topstone 105 SE, a much-used 2011 Specialized Secteur and very niche belt drive Trek District 1.

If you've ever wondered how we got into mountain biking and how the MuddyMoles started, well wonder no more.

There are 2 comments on ‘YT Jeffsy 29 AL – 2017 specification and geometry’

We love to get comments from our readers - if you've spent a few moments to comment, thank-you.

  1. Related: A new carbon YT Jeffsy appears for 2019 | 2019, News | Muddymoles: Mountain biking (MTB) in the Surrey Hills and Mole Valley

  2. Greg says:

    Great, thanks Matt. Just got this model second hand, very useful info.

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