I couldn't get enough power with mine untill a mechanic in the LBS showed me a simple trick. Tension the cable untill the pads hit the rim, set both pads so they are touching the rim with the full surface, tighten them as strong as you can wthout breaking anything, slacken the cable a bit and fine tune with the barrel adjuster. Your DX should be similiar to mine in design, which are STX, and are as strong as any V-brakes I rode with.
I couldn't get enough power with mine untill a mechanic in the LBS showed me a simple trick. Tension the cable untill the pads hit the rim, set both pads so they are touching the rim with the full surface, tighten them as strong as you can wthout breaking anything, slacken the cable a bit and fine tune with the barrel adjuster. Your DX should be similiar to mine in design, which are STX, and are as strong as any V-brakes I rode with.