disclaimer: bike repair newbie here


bike: 2004 specialized allez elite shimano 105, triple chainring, 9 speed cassette

currently my bike is not wanting to shift into the lowest gear (largest sprocket on the cassette). the chain will hop back and forth from the lowest gear to the second lowest gear when i shift all the way down.

i've adjusted the set screw on the RD to no avail. gears seem to be indexing fine otherwise. does this sound like a bent hangar?