YT Jeffsy Primus 27 in Review
26.09.23 06:21 2242023-09-26T06:21:00+02:00Text: VictorM, NoMan (translated by AI)Photos: Erwin HaidenYT's Shredder for Kids in the hands of a bike-enthusiastic junior. What does Victor say about the new 150-mm fully from the Forchheimers, which - attention, saving tip! - is currently 400 euros cheaper?26.09.23 06:21 4822023-09-26T06:21:00+02:00YT Jeffsy Primus 27 in Review
26.09.23 06:21 4822023-09-26T06:21:00+02:00 VictorM, NoMan (translated by AI) Erwin HaidenYT's Shredder for Kids in the hands of a bike-enthusiastic junior. What does Victor say about the new 150-mm fully from the Forchheimers, which - attention, saving tip! - is currently 400 euros cheaper?26.09.23 06:21 4822023-09-26T06:21:00+02:00
Hello everyone! If I may introduce myself briefly: My name is Victor, I'll be turning 13 in a few days, and I live in Wiener Neustadt and Winzendorf.
I've been biking with my father for almost seven years. We often ride on the Wechsel Trails, or on our home trails in the Fischauer Vorberge. We've also had mountain biking holidays in Flachau and Leogang.
And because the Bikeboard editorial team knows all this, they asked me a few months ago if I would like to review the new youth bike from YT in 27.5" along with some cool accessories - more on that shortly in a separate story -.
Hello?! What a question! Of course, I wanted to!
In the video, the Jeffsy looked like an adult bike, so I was hugely excited.
Victor googled, saw, and loved.
When I found out that I was allowed to review the YT Jeffsy Primus 27, I immediately googled it. Since it was still brand new at that time, there was no detailed information available, only the video with Leon Zimmermann. In the clip, it looked like an adult bike, so I was really excited.
In reality, though, it looked even cooler. My friend Andy from the village immediately stopped in front of our house when he drove by and saw the bike in the garden.
At first glance, the wide handlebars are striking, but I find they are just perfect for me. I haven't slipped off the ODI grips even once.
I find the color extremely cool. It's not conspicuously flashy, but very special. This turquoise shade just looks super good! In general, the Jeffsy looks just as good as an adult bike, and I think that's cool.
What's also great is that the manufacturer includes an extra small water bottle with these magnetic closures, so you always have water with you. I don't think a normal water bottle would fit in the frame.
Tech Specs
| Frame: | Aluminum, 27.5", Boost standard, 150 mm, (24": 130 mm, 26": 140 mm) | Headset: | Acros AZX-576 |
| Sizes: | 24/26/27" | Tires: | Maxxis Minion DHF 27.5x2.4"/Maxxis Minion DHR II 27.5x2.3" |
| Fork: | RockShox Lyrik Base RC 27.5", 150mm, 100x15 mm, Offset 44 mm | Wheels: | Sunringlé Duroc 35, Aluminum, inner width 31 mm, 27.5" |
| Shock: | RockShox Deluxe Select, installation length 230 mm, stroke 60 mm, Custom Tune 0L1 | Stem: | E13 Base 35, 6061 Aluminum, clamp 35 mm, Rise 0°, 40 mm |
| Shift lever: | Sram SX Eagle 12-s | Handlebar: | E13 Base 35, 6061 Aluminum, Rise 20 mm, 9° Back Sweep, 5° Up Sweep, 760 mm |
| Rear derailleur: | Sram SX Eagle 12-s | Grips: | ODI Elite Motion V2.1, Lock-on |
| Crank: | Sram SX Eagle, 32 T., 165 mm, DUB | Seat post: | YT Postman, Standard-Remote, 31.6 mm, 125 mm |
| Cassette: | Sram PG1210 Eagle 12-s, 11-50 T. | Saddle: | SDG Bel Air 3.0, YT Custom, width 140 mm |
| Chain: | Sram 12-s | Weight: | 15.38 kg (BB measurement) |
| Brake: | Sram G2 R, CL, 200 mm front/rear | Price: | MSRP € 2,399,- currently € 1,999,- |
When I sit on the YT, I feel that I can operate everything much easier than on my old bikes, and the suspension travel of the shock and fork are just perfect for me.
Also, nothing rattles, neither when jumping nor when riding normally off-road. However, I find the bike a bit heavy. Not necessarily while riding, as I hardly notice the fifteen and a half kilos. But when I have to push it a few meters uphill, for example, because I want to ride a difficult section again, it's really exhausting.
I can, of course, only speak for my weight class, but the brake is really top-notch! The levers are very easy to operate and can be easily adjusted to one's needs. The adjustment of the grip width is great.
In general, the size of the brake levers and also the size of the shift levers are good for me. I had no problems getting used to them. The shifting is super easy to operate and is just right for my hands. The chain shifts to the next gear shortly after shifting.
Geometry
| Size | 24 | 26 | 27 |
| Top tube length (mm) | 495 | 533 | 567 |
| Reach (mm) | 370 | 397 | 422 |
| Stack (mm) | 509 | 549 | 598 |
| Seat tube length (mm) | 315 | 355 | 395 |
| Chainstay length (mm) | 395 | 415 | 432 |
| Head angle | 65.5/66.2° | 65.5/66.4° | 65.7/66.2° |
| Seat angle (eff.) | 76.2/77° | 76/76.8° | 76.4/77.0° |
| Bottom bracket drop (mm) | 4/12 | -5/4 | 13/6 mm |
| Bottom bracket height (mm) | 316/324 | 340/349 | 344/352 |
| Wheelbase (mm) | 1045 | 1105 | 1167 |
| Head tube length (mm) | 95 | 95 | 110 |
| Standover height (mm) | 580 | 628 | 676 |
With the larger wheels, I have absolutely no problems riding (I had my initial doubts), on the contrary. They roll much better over obstacles and in terrain in general, and the grip of the wide tires is also great for the conditions I ride in.
Only practicing wheelies is much harder for me with the 27.5" wheels. I haven't really gotten the hang of it with the Jeffsy yet.
The travel of the fork and shock is totally sufficient. As I said, I can only speak for my weight class; currently, I weigh about 42 kilos.
What I also like: The frame is built in such a way that I can always shift my center of gravity exactly according to the current riding situation. This works a bit better on the Jeffsy than on my old bikes that I had before.
For the saddle and seat post, I noticed the biggest differences to my previous bikes when riding uphill. The ones from YT are much more comfortable!
Adjusting the seat post is also much easier for me to manage than on my last bike, the lever is much easier to operate.
The Facts about the YT Jeffsy Primus 27
For those who do not want to sift through our complete presentation from the spring for the numbers and data rounding off Victor's impressions:
Now available in 27.5" in addition to 24 and 26", the YT Jeffsy Primus offers real trail fun for riders with a body height of 135 to 165 cm.
Even the smallest bike in the series offers 130 mm of travel. This value increases to 150 mm for the night blue newcomer, made available through a new Rockshox Lyrik Base fork with Debonair+ air spring and Rush RC shock as well as the Deluxe Select shock with Custom Tune.
As with the Primus 26, an E13 Base cockpit with ODI grips, a Sram SX Eagle 12-speed drive, and 165-mm cranks are installed. A 125 mm YT Postman Dropper and the SDG Bel Air 3.0 provide freedom of movement downhill and comfort uphill, while the 27.5" Sunringle Duroc 35 wheels with Maxxis DHF & DHR II tires promise optimal grip under all conditions.
In summary, this results in 15.4 kg of concentrated shredding power, which can be owned in return for a RRP of €2,399,- (currently YT is offering a discount of 17% and selling the model for €1,999,-).
On the Jeffsy, I can always shift my center of gravity exactly according to the current riding situation.
In addition to the bike's appearance and the easy-to-use controls, Victor also really likes the geometry.
Conclusion
| YT Jeffsy Primus 27 | |
|---|---|
| Model year: | 2023 |
| Review duration: | 3 months |
| Price: | € 2,399,- RRP |
| + | Appearance and color |
| + | Ergonomics |
| + | thoughtfully equipped/tuned |
| + | good handling |
| + | special water bottle included |
| o | large wheels - great for riding, boo for wheelies |
| - | Weight |
| BB-Verdict: | Cooler than an adult bike! |
There's so much about the YT Jeffsy Primus 27 that I find simply great: It looks at least as cool as the adults' bikes, if not even better due to the very special color. It rides really well and is equipped and tuned from the grips to all levers, fork, and shock in such a way that everything is easy to operate and use even with small hands or little weight. And it's built in a way that I can always shift my weight well. Plus, I really like the saddle.
Contrary to my initial fears, I get along super well with the large wheels when riding. And the wide tires hold up great! Only when practicing wheelies do I still struggle a lot with the 27.5".
Speaking of heavy: The total weight of the bike doesn't bother me while riding, but pushing it, those well over 15 kilos do weigh quite a bit. Otherwise, I have nothing to criticize about the Jeffsy.
All in all, the review was a top experience for me. Thanks to Bikeboard or the manufacturers for this opportunity!
Maybe I'll see one of you on this bike, then we can happily exchange more thoughts...
Best regards, Victor
