Jamis Bikes’ New Hardline and Portal Trail Machines Are Here
PORTAL A1+
29″/27.5+
130mm rear wheel travel | HiLo bottom bracket adjust | Enduro Max sealed bearing pivots
12x148mm rear hub spacing | Custom Jamis upper chainguide mount | ISCG05 lower 2-bolt chainguide mount
HARDLINE A1
27.5″ / 27.5+ / 26+
160MM REAR WHEEL TRAVEL | ENDURO MAX SEALED BEARING PIVOTS | 12X148MM REAR HUB SPACING
CUSTOM JAMIS UPPER CHAINGUIDE MOUNT | ISCG05 LOWER 2-BOLT CHAINGUIDE MOUNT
Draw straight lines through the pivot locations of most dual-link designs, and you’ll find they intersect at a point somewhere in front of the bike’s bottom bracket. This “instant center” changes as the suspension compresses, altering the point around which the rear axle rotates.
The relationship of this constantly changing instant center to the line your chain traces as it travels from the gears of your cassette to the top of your chainring determines how well the bike pedals and how sensitive it is to bump forces.
Unlike most dual-link designs, the 3VO system’s unique instant-center path maintains consistent alignment with the chainline.
The instant center of the 3VO system starts from a position approximate to the center of the bike’s bottom bracket. From this position it moves rearward while remaining highly aligned with the driveline of the bike. The relationship of this constantly changing instant center to the line your chain traces as it travels from the gears of your cassette to the top of your chainring determines how well the bike pedals and how sensitive it is.
The majority of “forward instant center” designs focus on aligning the instant center and chainline during only one stage of the system’s movement. The performance of these designs often varies a great deal, depending on gear combination, terrain, pedaling effort, and where in its travel the rear axle is positioned. These systems often require precise setup of suspension sag and even specially tuned shocks in order to function properly.
Unlike these less predictable designs that project an instant center out in front of the bike’s bottom bracket, the 3VO system projects an instant center behind the bottom bracket and directly along the chainline. The 3VO system’s patented rearward instant center is more effective and consistent than conventional dual-link designs because it locates each of its instant center points along the chainline. The 3VO system’s instant center path also creates a consistent anti-rise response and an anti-squat response near 100% throughout the travel range, counteracting rider weight transfer under both braking and acceleration to keep all pedal input driving you forward while allowing the suspension to remain active and responsive to impacts, even while pedaling and braking. www.jamisbikes.com
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