Out of the box, the YT Jeffsy Core 2 is a quick build. Much of the set-up is a fairly quick process and is made all the easier by YT’s neat axle stands and step-by-step guide in the manual. Riders of all abilities should be able to get their Jeffsy together without having to venture to a bike shop, that said if you’re uncomfortable with any of the steps then we’d highly recommend getting a professional mechanic involved. Incorrect installation and poor maintenance of mountain bikes is dangerous!
Once the Jeffsy was set up, we removed the OE spec’d Maxxis Tires and installed our Versus All-Mountain Trail Casing tires, while also converting to a tubeless set-up. All our test bikes ran 25psi in the front tires and 27psi in the rear tires for a level playing field. Our fork air pressure was similar on all bikes whereas the rear shock took a bit of figuring out to get the right pressure for recommended sag. YT does have a suspension set-up guide on their website, which you can find here. However, the Jeffsy Core 2 was not listed during our test period. We’d love to see a table of suggested shock pressures for specific rider weights added to the manual or website for all current models, to help speed up the initial suspension setup process.
The YT Jeffsy’s climbing prowess was not anything special, however, it was not terrible either. Some of our testers felt the bike bobbed a bit more than others in our roundup, creating extra effort on steeper ascents, while a couple of other riders did not notice an issue at all. Thankfully the 3-position compression lever on the Fox shock is easily accessed to quickly add some extra support to improve its manners on the way up. One thing we all agreed on was the less than desirable shifting performance of the SRAM NX Eagle drivetrain. Compared to the Shimano 12-speed equipped bikes in our lineup, the shifting was dull and not always exact, usually requiring a stiffer push on the shifter to get it into the next gear, whether that be up or down.
Robert did a great job summarizing the Jeffsy’s downhill capabilities in his review of the Core 4 model and not much is different on the Core 2 model tested here. Obviously, the biggest difference comes in the form of Fox’s Factory spec versus their Performance line of suspension parts. The 36 Performance fork is a solid spec at this price point (and the top spec in this group review) and performed well during a test period. The Performance DPX2 also held its own for the most part, however, an additional volume reducer may have helped liven the Jeffsy up a bit more. The Jeffsy Core 2 was not the liveliest of bikes in our round-up. It had a tendency to mute some of the trails out and stay stuck to the ground. That is not necessarily a bad thing and was a highlight for some of our testers as it provides a more comfortable and predictable ride.
Outside of our issues with the poor shift feeling of the NX Eagle drivetrain, there are a couple of other specs we have some qualms with. The 150mm Postman dropper post is too short for large frames, a 170mm+ option would be the better spec in our opinion. The G2 R brakes are another area of concern (for some of our riders), these SRAM brakes can get overheated quickly on steep terrain and braking can become an issue. On some of our laps, these brakes were the only ones to show signs of brake fade intermittently. We don’t think they need to be replaced right away, but we do believe they should be one of the first upgrades made on this particular bike. When it comes to the remainder of the build, YT did an excellent job with the spec they chose, certainly offering the most bang for the buck in this test, in our opinion.
The Wolf’s Last Word
The YT Industries Jeffsy Core 2 as an affordable mountain bike, is an impressive all around machine that will let you progress as a rider. It stood out amongst the other bikes in our sub-3k group review. While the Jeffsy is efficient enough going uphill, the bike much prefers going with gravity than against it…like the rest of our crew. The YT Jeffsy is capable of eating up everything that comes its way: whether it be techy rock gardens, flow trails or catching air, it will do it all with ease. It is also one of the only bikes that we would consider bringing to the bike park.
Who do we think this bike is for you might ask? For the ripper or the beginner. Those who like to shred trail or play on side hits will be at home the YT Jeffsy Core 2, though the limit will be found sooner or later as components and travel will become barriers if you’re repeatedly hitting the gnarliest of descents. For beginners, the YT Jeffsy Core 2 will allow them to grow into the bike, as it is not pigeon-holed into only being able to ride a certain type of trail while more advanced riders on a budget will appreciate they can push this bike hard and be rewarded with a capable mountain bike at a fair price.
Weight: 34.8 lbs (as tested)