If you look at Aaron Gwin’s Instagram account, you’ll very often see the fast American onboard the YT JEFFSY 29 CF Pro Race. The bike won us over too, but unfortunately, it wasn’t enough to beat the competition.

For an overview of the test fleet head to the group test: The best trail bike you can buy

All bikes in test: Canyon Spectral CF 9.0 LTD | Evil Offering X01 | Giant Trance Advanced Pro 29 | Ibis Ripmo | Pivot Mach 5.5 Pro XT | Propain Hugene Highend | Rocky Mountain Thunderbolt BC Edition | Santa Cruz Bronson CC X01+ | Scott Genius 900 Ultimate | Specialized S-Works Stumpjumper 29 | Transition Sentinel X01 | Trek Remedy 9.9 | YT Jeffsy 29 CF Pro Race

YT JEFFSY 29 CF PRO RACE | 140/140 mm (f/r) | 12.90 kg | € 4,999

After the introduction of the YT CAPRA, things have become a bit quieter around the JEFFSY. Nonetheless, the trail bike is still the first choice for many riders, even if it has started to look a bit outdated in spite of the pretty paintwork. The completely external cable routing is practical, but no longer up to date. As you’d expect from YT, you get a lot of excellent components for the fair price of € 4,999: the suspension consists of a FOX 34 fork and a DPX2 shock – both Factory, of course. For the drivetrain, YT relies on a combination of a Shimano XTR rear derailleur and an E13 crank and cassette. This setup isn’t only lighter than an Eagle drivetrain, it also offers a wider gear range, and according to YT, more reliable shifting. The carbon rims and the tires are also from E13. Unlike the CAPRA, the JEFFSY offers room for a water bottle – even if only for a small one, 500 ml should be enough for a quick after-work ride.

  Really composed. Compared to the brand image, the handling of the JEFFSY is almost too well behaved.

The YT JEFFSY 29 CF Pro Race in detail

Fork FOX 34 FLOAT FACTORY 140 mm
Schock FOX FLOAT DPX2 FACTORY 140 mm
Brakes SRAM GUIDE ULTIMATE 200/180 mm
Drivetrain Shimano XTR/e*Thirteen
Seatpost FOX Transfer Factory 150 mm
Stem Renthal APEX 35 50 mm
Handlebar Renthal FatBar Carbon 35 800 mm
Wheelset E*thirteen TRS Race SL Carbon
Tires E*thirteen TRS+
Weight 12.90 kg
Price € 4,999

Unusual
The combination of the E13 cassette and the Shimano XTR rear derailleur is unusual, but it performs brilliantly and offers the largest available gear range at 511%.
Old school
The externally routed cables are a little untidy and, together with the slim shape of the frame, the bike looks a bit outdated.
Angular
Not only do the E13-TRS tires roll poorly, but they also have a very square design, which means that they lose grip very suddenly and tend to fold easily.
Thirsty
The 500 ml water bottle isn’t huge, but it should be enough for most after work rides. For longer rides, you would usually carry a backpack or hip bag anyway.

Die Geometrie des YT JEFFSY 29

Size S M L XL
Seat tube 400 mm 440 mm 480 mm 520 mm
Top tube 571 mm 592 mm 616 mm 637 mm
Head tube 90 mm 95 mm 110 mm 115 mm
Head angle 67° 67° 67° 67°
Seat angle 74,5° 74,5° 74,5° 74,5°
Chainstay 435 mm 435 mm 435 mm 435 mm
BB Drop 32 mm 32 mm 32 mm 32 mm
Wheelbase 1132 mm 1154 mm 1178 mm 1205 mm
Reach 405 mm 425 mm 445 mm 465 mm
Stack 605 mm 610 mm 623 mm 628 mm
Helmet Troy Lee A1 | Glasses Oakley Jawbreaker | Backpack EVOC STAGE 12 l | Jersey Troy Lee Designs Sprint | Short Troy Lee Designs Ruckus

The YT JEFFSY 29 CF Pro Race on the trail

YT makes no secret of the fact that having fun on the descents is their top priority. Nevertheless, the JEFFSY climbs surprisingly well. However, it is advisable to push the saddle as far forward as it’ll go so you don’t pedal from too far back. On long, easy climbs, it’s also worth reaching for the climb switch to stop the shock from bobbing as you pedal. If climbing efficiency is important to you we recommend replacing the slow rolling E13 tires. But, as it is, you’ll be able to reach the top of every trail onboard the JEFFSY. Descending, the JEFFSY delivers a lot of good times. It’s handling is very balanced, which is certainly also due to the increased length of the chainstays in sizes L and XL. The weight distribution is nicely centred and the handling is easy and intuitive. The rear linkage works very sensitively without using its travel too quickly. It absorbs large blows with ease and outperforms the FOX 34 fork. We missed about a centimetre more travel at the front, which would also slacken the head angle a bit. A longer travel fork would increase the bike’s composure on very steep and fast tracks.

Tuning tip: more powerfull brakes

Conclusion

The YT JEFFSY CF PRO Race is not as extreme as some might think. It scores with very balanced, good-natured handling and an excellent rear linkage. The fork, or rather the steep head angle limits the potential of the bike on demanding trails.

Tops

  • good value for your money
  • good-natured, predictable handling
  • excellent rear linkage

Flops

  • Head angle somewhat steep / not enough travel on the fork
  • externally routed cables seem outdated

Uphill

Downhill

Stability

Agility

Value for money


More info at: yt-industries.com

For an overview of the test fleet head to the group test: The best trail bike you can buy

All bikes in test: Canyon Spectral CF 9.0 LTD | Evil Offering X01 | Giant Trance Advanced Pro 29 | Ibis Ripmo | Pivot Mach 5.5 Pro XT | Propain Hugene Highend | Rocky Mountain Thunderbolt BC Edition | Santa Cruz Bronson CC X01+ | Scott Genius 900 Ultimate | Specialized S-Works Stumpjumper 29 | Transition Sentinel X01 | Trek Remedy 9.9 | YT Jeffsy 29 CF Pro Race


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