THE WIDE RIM REVOLUTION!
OPTIMIZING THE PERFORMANCE OF MOUNTAIN BIKE TIRES:
The wider sidewall raises the edge knobs without raising the center knobs, which makes a less round or more "square" tread cross-section profile.
Also the tire casing tension under the edge knobs is increased to be firmer, increasing the tire's stability, and allows lower tire pressure when desired for less rolling resistance over rough terrain from increased bump compliance, and a larger tire patch when weighting the tires while braking and cornering.
Cornering traction is much improved on dusty hardpack to very loose gravelly dirt or loamy covered with leaves, as a result of this combination of flatter tread cross section, stiffer edge knobs, more knobs in contact, and lower air pressure, all enabled with wide rims.
Changing direction has quicker response with the more stable and firmer structural tire edge with wide rims, without feeling harsh and choppy, and no more sudden washing-out of the front wheel, or as easily skidding the rear tire while cornering.
The whole bike becomes more stable on wide rims, feeling like a longer wheelbase bike in directional control but with quicker more positive turn response for more nimble handling and corning grip. Holding a line over loose round rocks though "rock gardens" becomes much easier, without getting kicked side to side when not centered over each loose rock.
The result of going to wide rims with the same tires is immediate increase in confidence while riding loose dusty, gravely, rocky, and wet conditions; enabling higher speeds, harder braking, and more precise and predictable cornering.
XC, AM, DH layup options - for 2.0 to 2.8 tires
Weight +/-10: 460g [XC] or 485g [ All-Mountain or 525g [Downhill]
BSD: 622mm
Outer width: 35mm
Inner width: 29mm
ERD: 582mm (DH add 1mm) – Always measure to confirm
29r AM Rim impact force test: 224KgF (494lbs, cracks at valve hole, 90' from force)
29r AM Spoke pull force test: 326KgF (719lbs, spoke broke, no rim damage)
AM, DH layup options - for 2.2 to 3.0 tires
Weight +/-10: 465g [All-Mountain] or 545g [Downhill]
BSD: 584mm
Outer width: 40mm
Inner width: 34mm
ERD: 542mm (DH add 1mm) – Measure to confirm
AM Rim impact force test: 267KgF (588lbs, cracks at valve hole, 90' from force)
AM layup - for 2.8 to 3.5 tires
Weight +/-10: 530g [All-Mountain]
BSD: 584mm
Outer width: 50mm
Inner width: 44mm
ERD: 538mm – Measure to confirm
Spokes off-set from rim center: 5mm
AM Spoke pull force test: 352KgF (775lbs, spoke broke, no rim damage)
XC, AM layup options - for 2.5 to 3.2 tires
Weight +/-15: 520g [XC or AM]
BSD: 622mm
Outer width: 45mm
Inner width: 39mm
ERD: 582mm – Always measure to confirm
Spokes off-set from rim center: 5mm
29rx45 XC Rim impact force test: 436KgF (961lbs, cracks at valve hole, 90' from force)
29rx45 XC Spoke pull force test: 325KgF (717lbs, spoke broke, no rim damage)