Who the hell is Jeffsy? It’s a question that has set the mountainbike forums on fire over the last few weeks! YT Industries have finally let the cat out of the bag, Jeffsy is a trail bike! We’ve got all the details on the new YT Jeffsy and you’re about to get a massive surprise:

Love it or hate it: das neue YT Jeffsy CF Pro. Mit Top-Ausstattung geht es für 4.499 € über den virtuellen Ladentisch.
Love it or hate it, the new YT Jeffsy CF Pro. With top spec, it retails for € 4,499 in YT’s online store.

One thing was clear long before the presentation of the new bike: regardless of the bike category, the guys from YT Industries would never compromise on the downhill performance of their bikes! So it’s no surprise that the new 140 mm trail bike boasts an aggressive geometry, YT’s proven virtual 4-link suspension concept and top tier componentry that fit the bill of a downhill biased trail bike flawlessly.

“The goal was to build a trail rocket that is light, comfortable to ride and invites the rider to shred – and on top of everything it was supposed to look damn good” Stefan Willared, CTO of YT Industries, enthused about the new bike.

Happy mit dem Ergebnis: Stefan und Markus präsentieren stolz das neue YT Jeffsy.
Happy with the result: Stefan and Markus proudly present the new YT Jeffsy.

The biggest surprise of the YT Jeffsy

We all knew that the team behind YT Industries would come up with a shorter travel trail bike sooner or later. But nobody was expecting it to roll on 29er wheels! Even within the company, there was considerable scepticism: “We didn’t want to build a 29er necessarily. We simply tried to build the best trail bike and during the development process, this wheel size proved to be ideal!” Stefan said. While the bigger wheels offer more grip and better rollover characteristics, the biggest advantage was arguably the lower bottom bracket in relation to the wheel axles, that allows riders get a very integrated position on the bike. “With this bike you destroy berms!” Markus Flossmann, CEO of YT Industries, grins.

Die großen Laufräder fügen sich optisch hervorragend ins Gesamtbild ein. Erst auf den zweiten Blick wird klar, dass hier keine 27,5"-Räder verbaut sind.
The bigger wheels blend into the overall appearance perfectly. Only on the second glimpse it becomes evident that this is not a 27.5” bike.
Wie schon beim Enduro-Modell Capra wird auch beim Jeffsy der Dämpfer über die Sitzstrebe angelenkt.
Like on the enduro focussed Capra, the shock pivot of the YT Jeffsy is mounted directly into the seat stays.
Typisch für YT: der Schriftzug seitlich am Steuerrohr.
Typical for YT: the logo on the side of the head tube.
Wichtig für ein Trailbike: Platz für eine Trinkflasche. Das Jeffsy bietet Raum für eine 0,5-l Flasche die von YT speziell entwickelt wurde – ebenso wie der Flaschenhalter aus Carbon.
Important for a trail bike: room for a water bottle. The Jeffsy accommodates a 0.5 l bottle that was specifically designed by YT – just like the carbon bottle mount.
Die Züge werden auf dem Oberrohr geführt. Das erleichtert die Wartung, ermöglicht optimale Radien und sorgt so für weniger Reibung.
The cables run on top of the downtube. This makes maintenance easy, allows smooth radii and consequently less friction.

What led to the YT Jeffsy?

For almost three years Stefan Willared and his development team worked on a trail bike that would rule on home trails, multi-day adventure rides, alpine single track and enduro races alike. During the development process, 29” wheels turned out the be the best for these requirements. According to Stefan, his team desperately wanted to avoid creating “a bike/rider ensemble that looked like a monkey riding an ostrich”. Therefore, the goal was not only to pick up the distinctive look of other YT models but also to integrate the big wheels subtly within the appearance of the new bike – and we think this was achieved brilliantly.

Am Anfang des Entwicklungsprozesses stand die Zeichnung auf Papier.
The pencil drawings marked the beginning of the development process.
Hier wurden unzählige Rohrshapes und Designs ausprobiert.
The designers experimented with a myriad of tube shapes and designs.
Später folgten 3D-gedruckte Samples in Klein …
The next step were 3D-printed miniature samples of the frame …
… und  noch später auch in Groß.
… followed by life-size prototypes.
Komplett gedruckt und mit einem Dämpfer-Dummy versehen, ließ sich bereits die Freigängigkeit des Hinterbaus überprüfen.
Equipped with a shock dummy, the 3D-samples were used to assess the tyre clearance.
Flasche und passender Flaschenhalter wurden ebenfalls speziell für das Jeffsy konstruiert.
The water bottle cage and the matching bottle were specifically designed for the Jeffsy.
Am Flaschenhalter lässt sich direkt eine Luftpumpe fixieren – praktisch!
A pump can be attached directly to the water bottle mount – useful!

The geometry of the YT Jeffsy

As soon as you read the geometry numbers you know one thing, this bike is built for shredding! A slack 66.8° head tube angle, mated with short 435 mm chain stays (in size S/M, 440 mm in L/XL) and a mainstream front center length with a reach of 445 mm in size L sounds like just the recipe for hitting trails at crazy speeds. Riders coming from longer travel bikes will appreciate the benefits of a riser bar and therefore the stack of the Jeffsy was designed with 25 mm riser bars in mind. A flip chip in the seat stays allows riders to fine tune the geometry to their personal preferences (0.8° steeper). However, with a steep 74.7° seat tube to maximise pedalling efficiency, we cannot see why you would want to sacrifice downhill performance.

An einem Bike, das für maximalen Spaß in der Abfahrt konzipiert ist, darf ein breiter Lenker mit Rise auf keinen Fall fehlen.
A bike that is designed for maximum downhill performance should never lack wide riser bars.
Für maximalen Spaß auf flachen Trails und bergauf macht ein etwas längerer Vorbau absolut Sinn. Mit 60 mm ist er aber immer noch ausreichend kurz, um ein direktes Handling zu gewährleisten.
For maximum fun on flat trails and uphill, a slightly longer stem makes perfect sense. With 60 mm it’s still short enough, to offer direct handling when the trail points downwards.
Größe S M L XL
Lenkwinkel 66,8°/67,6° 66,8°/67,6° 66,8°/67,6° 66,8°/67,6°
Seat Tube Angle 74,7°/75,3° 74,7°/75,3° 74,7°/75,3° 74,7°/75,3°
Top Tube 571,1 mm 592,3 mm 616,1 mm 637,4 mm
Head Tube Length 90 mm 95 mm 110 mm 115 mm
Seat Tube Length 400 mm 440 mm 480 mm 520 mm
BB drop 32/24 mm 32/24 mm 32/24 mm 32/24 mm
Chain Stay Length 435 mm 435 mm 440 mm 440 mm
Wheelbase 1132 mm 1154 mm 1184,7 mm 1206,7 mm
Stack 605 mm 609,6 mm 623,4 mm 628 mm
Reach 405 mm 424 mm 445 mm 465 mm

Specification of the YT Jeffsy

As to be expected from Young Talent, the Jeffsy will be available in several well-sorted specs at killer prices, and with shipping starting at the end of April we expect this bike to be in high demand. The German brand will offer three aluminum and three carbon models ranging from € 2,199 to € 4,499. The suspension on all the models was tuned in close collaboration with RockShox and FOX. While three versions feature SRAM 1-by drivetrains, the remaining three come with Shimano 2-by setups, catering to those that are still not convinced by the benefits of 1-by solutions. Given a choice, we’d always go for the former.

Sowohl das FOX- als auch das RockShox-Fahrwerk verfügt ab Werk über Volumen-Spacer für eine progressivere Kennlinie des Hinterbaus. Ein Hinterbau mit angenehmem „Popp“ ist das Resultat, sagt Stefan.
Both the FOX and RockShox shocks come with volume spacers pre-installed to achieve a progressive suspension curve. Stefan claims, the result is a rear end with a pleasant degree of “pop”.

The models of the Jeffsy at a glance

YT Jeffsy CF Pro

  • Weight: 11,9 kg
  • Price: 4.499 €
  • Colors: Red & Raw (black)
  • Fork: FOX 34 Float Factory
  • Rear Shock: FOX Float DPS Factory
  • Drivetrain: SRAM X01 / Race Face Next SL
  • Brakes: SRAM Guide Ultimate
  • Seatpost: RockShox Reverb Stealth
  • Stem: Renthal Apex
  • Bar: Renthal Fatbar Carbon
  • Tyres: Onza Ibex
  • Wheels: DT Swiss XMC 1200 Spline

YT Jeffsy CF Comp 1

  • Weight: 12,8 kg
  • Price: 3.599 €
  • Colors: Snow White & Jet Black
  • Fork: RockShox Pike RCT3
  • Rear Shock: RockShox Monarch RT3
  • Drivetrain: SRAM X1 / Race Face Turbine
  • Brakes: SRAM Guide RSC
  • Seatpost: RockShox Reverb Stealth
  • Stem: Race Face Turbine
  • Bar: Race Face Turbine
  • Tyres: Onza Ibex
  • Wheels: DT Swiss M1700 Spline

YT Jeffsy CF Comp 2

  • Weight: 13,3 kg
  • Price: 3.599 €
  • Colors: Blue Lagoon & Jet Black
  • Fork: RockShox Pike RCT3
  • Rear Shock: RockShox Monarch RT3
  • Drivetrain: Shimano XT / Race Face Turbine
  • Brakes: Shimano XT
  • Seatpost: RockShox Reverb Stealth
  • Stem: Race Face Turbine
  • Bar: Race Face Turbine
  • Tyres: Onza Ibex
  • Wheels: DT Swiss M1700 Spline

YT Jeffsy AL Comp 1

  • Weight: 13,5 kg
  • Price: 2.799 €
  • Color: Black/Red
  • Fork: RockShox Pike RCT3
  • Rear Shock: RockShox Monarch RT3
  • Drivetrain: SRAM GX / Race Face Turbine
  • Brakes: SRAM Guide RS
  • Seatpost: RockShox Reverb Stealth
  • Stem: Race Face Turbine
  • Bar: Race Face Turbine
  • Tyres: Onza Ibex
  • Wheels: DT Swiss M1900 Spline

YT Jeffsy AL Comp 2

  • Weight: 14,1 kg
  • Price: 2.799 €
  • Color: Black/White
  • Fork: RockShox Pike RCT3
  • Rear Shock: RockShox Monarch RT3
  • Drivetrain: Shimano XT / Race Face Turbine
  • Brakes: Shimano XT
  • Seatpost: RockShox Reverb Stealth
  • Stem: Race Face Turbine
  • Bar: Race Face Turbine
  • Tyres: Onza Ibex
  • Wheels: DT Swiss M1900 Spline

YT Jeffsy AL

  • Weight: 14,3 kg
  • Price: 2.199 €
  • Color: Black/Blue
  • Fork: RockShox Pike RC
  • Rear Shock: RockShox Monarch R
  • Drivetrain: Shimano SLX / Race Face Affect
  • Brakes: Shimano SLX
  • Seatpost: RockShox Reverb Stealth
  • Stem: Race Face Affect
  • Bar: Race Face Affect
  • Tyres: Onza Ibex
  • Wheels: DT Swiss M1900 Spline

Our Opinion

Unfortunately, we haven’t had the chance to test the brand new YT Jeffsy on the trails yet, but on paper, the new bike looks set to do battle with the best. Great geometry, proven suspension system and top-notch specs at a price point that will terrify the competition make the Jeffsy a hot contender in the 2016 trail bike market. 29er’s are now shrugging off their boring marathon bike image and we cannot wait to see how much Capra this bike has in its DNA!, Stay tuned for our full review!

Stefan und Markus lieben das Jeffsy bereits jetzt und auch wir können uns gut vorstellen, dass das Rad viele Fans finden wird!
Stefan and Markus love the Jeffsy already and we are confident, that the bike will find many fans!

For more information head to jeffsy.com or the YT Industries website.

Words: Christoph Bayer | Photos: Christoph Bayer/YT Industries

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