They have a great weight to stiffness ratio for fast excelleration out of the gate and corners. Available in front/disc brake and rear/rim-brake versions.
Weight
20 x 1.75" : 325g (f) 318g (r)
24 x 1.75" : 400g (f) 395g (r)
20 x 1 1/8" - 1 3/8" 36H: 355g (f) 350g (r)

20” x 1 1/8” - 1 3/8"
A= Internal Diameter (when eyelets, then eyelets to eyelets): 392mm
B= Rim Thickness (when eyelet, includes eyelet): 40mm
C= ERD: 472mm
20” x 1.75"
A= Internal Diameter (when eyelets, then eyelets to eyelets): 364mm
B= Rim Thickness (when eyelet, includes eyelet): 40mm
C= ERD: 444mm
24” x 1.75"
A= Internal Diameter (When eyelets, then eyelets to eyelets): 464mm
B= Rim Thickness (when eyelet, includes eyelet): 40mm
C= ERD: 544mm
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