The Valley Shuttle, which serves Pomona, Claremont, La Verne and San Dimas, will be discontinued Aug. 1 because of low ridership, according to the Pomona Valley Transportation Authority. Its funds will be used to supplement Dial-a-Ride, a service that allows passengers in the four cities to call a central number to request pickup. Since the two transportation services began last November, the Valley Shuttle has averaged about 30 riders a day while Dial-a-Ride has averaged about 400, said George Sparks, spokesman for the transportation authority. Hours for Dial-a-Ride are 6 a.m. to 7 p.m. in all four cities. Saturday service from 9 a.m. to 4 p.m. is available in Claremont, La Verne and Pomona. Sunday service is offered from 8 a.m. to 4 p.m. in Claremont only. The fare is $1.