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ALL MOUNTAIN

Far out or nothing - with JEFFSY we have realized our very own definition of trail riding. JEFFSY is the YT among all mountain bikes, it's like your best friend for new top performances: together you climb the higher mountains, discover the most remote places and stamp downhill with full speed - JEFFSY and you, you are an unbeatable team

Choose Your Wheel Size

all-mountain
?
Wheels: 29
?
CF
?

Jeffsy CORE 4 29

S

M

L

XL

XXL

S - Not Available

M - Not Available

L - Not Available

XL - Not Available

XXL - Ships Latest July 7, 2021

$5,199.00

We cut no corners for the highest CORE level – these uncompromising Factory Team level packages were made for taking on the most demanding terrain. The JEFFSY CORE 4 are equipped with the very best components and every little detail has been optimized for performance – from the high-end parts to the top-notch carbon frame. The suspension elements are fully adjustable to ensure that even the gnarliest trails are within your comfort zone. From the race track to the home trails, these bikes leave nothing to be desired – but that also means that there are no more excuses.

Send it over!
  • Material

    Carbon

  • Suspension

    150mm

Tech + Specs
  • Frame

  • Flip chip

  • Protection

  • Bearings

  • Chainsuck

  • Headtube

  • Internal Cable Routing

  • Virtual Four Link

Frame

Flip chip

Situated at the lower shock mount, the Flip Chip makes it quick and easy to adjust the geometry according to the terrain and riding style. The low position provides for a more aggressive headtube angle and a bigger BB drop, ideal for fast and rough tracks. In the high position, the headtube angle is 0.5 degrees steeper and the BB is higher. The higher BB gives more ground clearance and better performance on longer steep climbs.

Protection

Made from super-tough and wear-resistant PA 66, the downtube protector is bolted on and can be easily replaced. It is designed to wrap around the bottom bracket and thus provide extra protection for the side walls of the downtube from impacts and scratches. Additionally, the rubber chainstay and seatstay guards help prevent unwanted noise from the drivetrain.

Bearings

Extra seals protect the high-quality, double-sealed full complement bearings to keep water and dirt out and help prolong the service life.

Chainsuck

The inconspicuous chainsuck plates protect the frame from damage caused by a dropped chain. This keeps sensitive areas out of harm's way and helps prolong the frame's durability.

Headtube

The contact surfaces for the integrated headset are preformed directly in the carbon structure. The homogeneity of the material in this area creates the ideal balance of weight, durability and performance. The ZeroStack design with integrated bearings ensures a long service life.

Internal Cable Routing

For optimal protection, all cables are routed almost completely through the frame. Uninterrupted internal tubes provide for easy cable replacement and also help prevent unwanted noise. Small ridges ensure the cable plugs sit tight in the frame to seal the cable ports and a cable clamp holds them securely in place as they exit the frame under the rocker link.

Virtual Four Link

Our award-winning V4L suspension technology provides sensitivity off the top, with good mid-stroke support and plenty of end-stroke progressivity. The nice pop helps get the bike airborne whenever wanted, while the end-stroke progressivity makes sure the rear shock doesn't bottom out even on monster jumps. The high amount of anti-squat keeps the rear suspension neutral and improves pedal efficiency.

Flip chip

Flip chip

Situated at the lower shock mount, the Flip Chip makes it quick and easy to adjust the geometry according to the terrain and riding style. The low position provides for a more aggressive headtube angle and a bigger BB drop, ideal for fast and rough tracks. In the high position, the headtube angle is 0.5 degrees steeper and the BB is higher. The higher BB gives more ground clearance and better performance on longer steep climbs.

Protection

Protection

Made from super-tough and wear-resistant PA 66, the downtube protector is bolted on and can be easily replaced. It is designed to wrap around the bottom bracket and thus provide extra protection for the side walls of the downtube from impacts and scratches. Additionally, the rubber chainstay and seatstay guards help prevent unwanted noise from the drivetrain.

Bearings

Bearings

Extra seals protect the high-quality, double-sealed full complement bearings to keep water and dirt out and help prolong the service life.

Chainsuck

Chainsuck

The inconspicuous chainsuck plates protect the frame from damage caused by a dropped chain. This keeps sensitive areas out of harm's way and helps prolong the frame's durability.

Headtube

Headtube

The contact surfaces for the integrated headset are preformed directly in the carbon structure. The homogeneity of the material in this area creates the ideal balance of weight, durability and performance. The ZeroStack design with integrated bearings ensures a long service life.

Internal Cable Routing

Internal Cable Routing

For optimal protection, all cables are routed almost completely through the frame. Uninterrupted internal tubes provide for easy cable replacement and also help prevent unwanted noise. Small ridges ensure the cable plugs sit tight in the frame to seal the cable ports and a cable clamp holds them securely in place as they exit the frame under the rocker link.

Virtual Four Link

Virtual Four Link

Our award-winning V4L suspension technology provides sensitivity off the top, with good mid-stroke support and plenty of end-stroke progressivity. The nice pop helps get the bike airborne whenever wanted, while the end-stroke progressivity makes sure the rear shock doesn't bottom out even on monster jumps. The high amount of anti-squat keeps the rear suspension neutral and improves pedal efficiency.

sGeometry Sizefinder
S
154 cm - 165 cm | 5'1" - 5'5"
M
164 cm - 175 cm | 5'4.5" - 5'9"
L
174 cm - 184 cm | 5'8" - 6'0.5"
XL
183 cm - 193 cm | 6'0" - 6'4"
XXL
192cm - 202cm | 6'3.5" - 6'8"

This size table is only a suggestion. The optimal frame size depends also on your personal riding style.

Toptube
Reach
Stack
Seattube
Chainstay
Headtube Angle
Seattube Angle (eff)
bb drop
wheelbase
headtube
bb height
Standover height

s

m

l

xl

xxl

Toptube
572 mm
593 mm
615 mm
638 mm
660 mm
Reach
430 mm
450 mm
470 mm
490 mm
510 mm
Stack
618 mm
622 mm
627 mm
636 mm
640 mm
Seattube
400 mm
415 mm
435 mm
460 mm
485 mm
Chainstay
435 mm
435 mm
435 mm
440 mm
440 mm
Headtube Angle
66° / 66,5°
66° / 66,5°
66° / 66,5°
66° / 66,5°
66° / 66,5°
Seattube Angle (eff)
77° / 77,5°
77° / 77,5°
77° / 77,5°
77° / 77,5°
77° / 77,5°
bb drop
32 / 24 mm
32 / 24 mm
32 / 24 mm
32 / 24 mm
32 / 24 mm
wheelbase
1174 mm
1196 mm
1218 mm
1247 mm
1269 mm
headtube
100 mm
105 mm
110 mm
120 mm
125 mm
bb height
344 / 352 mm
344 / 352 mm
344 / 352 mm
344 / 352 mm
344 / 352 mm
Standover height
706 mm
702 mm
701 mm
693 mm
694 mm
 

s

m

l

xl

xxl

Toptube
572 mm
593 mm
615 mm
638 mm
660 mm
Reach
430 mm
450 mm
470 mm
490 mm
510 mm
Stack
618 mm
622 mm
627 mm
636 mm
640 mm
Seattube
400 mm
415 mm
435 mm
460 mm
485 mm
Chainstay
435 mm
435 mm
435 mm
440 mm
440 mm
Headtube Angle
66° / 66,5°
66° / 66,5°
66° / 66,5°
66° / 66,5°
66° / 66,5°
Seattube Angle (eff)
77° / 77,5°
77° / 77,5°
77° / 77,5°
77° / 77,5°
77° / 77,5°
bb drop
32 / 24 mm
32 / 24 mm
32 / 24 mm
32 / 24 mm
32 / 24 mm
wheelbase
1174 mm
1196 mm
1218 mm
1247 mm
1269 mm
headtube
100 mm
105 mm
110 mm
120 mm
125 mm
bb height
344 / 352 mm
344 / 352 mm
344 / 352 mm
344 / 352 mm
344 / 352 mm
Standover height
706 mm
702 mm
701 mm
693 mm
694 mm
Frame
Frame Size
Frame Size
 
S, M, L, XL, XXL
Color
Color
 
Vlad Red, Black Magic
Wheels
Wheels
DT SWISS XM 1700 SPLINE
 
Aluminum Rims 29“ | Inner Width 30 mm | Front Hub 110 x 15 mm | Rear Hub 148 x 12 mm I XD I Ratchet 36SL
Tires
MAXXIS MINION DHR II
 
Front Tire Size 29“ x 2.4 | EXO Casing | Tubeless Ready | 3C MaxxGrip Compound / Rear Tire Size 29“ x 2.4 | EXO+ Casing | Tubeless Ready | 3C MaxxTerra Compound
Suspension
Fork
FOX 36 FLOAT FACTORY
 
29“ | 150 mm Travel | Grip 2 | 110 x 15 mm Axle | 44 mm Offset
Shock
FOX FLOAT DPX2 FACTORY
 
Shock Length: 210 mm | Shock Stroke: 55 mm ≙ 150 mm Travel | 3pos-Adjust
Drivetrain
Crankset
SRAM Descendant Carbon
 
Crank Arm Length 175 mm | 32T I DUB-PressFit
Cassette
SRAM XG1295 EAGLE
 
10-52T | 12-speed
Rear derailleur
SRAM X01 EAGLE
 
12-speed
Shifter rear
SRAM X01 EAGLE
 
12-speed
Components
Headset
ZS44 ZS56 | High Cap | 2 Spacer 5 mm
 
ACROS AZX-576
Stem
RENTHAL APEX 35
 
50 mm |+/-6° | Black/ Gold
Handlebar
RENTHAL FATBAR 35
 
780mm | 30mm Rise | 7° Back | 5° Up | Custom Black
Grips
ODI ELITE MOTION V2.1
 
Lock-On
Brakes
SRAM G2 RSC
 
Rotor CENTERLINE Ø front 200 mm / rear 200 mm | Adjustable Bite Point and Reach
Seatpost
YT POSTMANMMX Remote
 
Ø 31.6mm | 125 mm (S-M) | 150 mm (L) | 170 mm (XL-XXL)
Saddle
SDG BEL AIR 3.0
 
YT Custom | Width 140 mm
Weight
Weight
13,90 KG / 30,64 LB
 
Average weight for smallest size available, without tubes, pedals, and bottle.
Jeffsy 2021

Jeffsy 2021

PDF | 6.21 MB

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Carbon Icon

Our carbon frames deliver ideal stiffness and ultimate reliability at impressively low weight. Using a monocoque production technique, tube walls get extra thickness only where required, to resist the intense forces in critical areas. By using fibers of different strengths and optimizing the layup, we create stiff yet lightweight frames that withstand even the gnarliestof maneuvers.

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