If you're looking for a reliable rim, the SD Double Wall Rim with Eyelets is the one you need.
Weight
20 x 1 1/8" 28h : 370g (f) 361g (r)
20 x 1 1/8" 36h : 376g (f) 363g (r)
20 x 1 3/8" 36h : 468g (f) 456g (r)
20 x 1.75" (451): 434g (f) 509g (r)
20 x 1.75" : 409g (f) 464g (r)
24 x 1.75" : 510g (f) 577g (r)