We studied the Kepler light curves of three SU UMa-type dwarf novae. Both the background dwarf nova of KIC 4378554 and V516 Lyr showed a combination of precursor-main superoutburst, during which superhumps always developed on the fading branch of the precursor. This finding supports the thermal-tidal instability theory as the origin of the superoutburst. A superoutburst of V585 Lyr recorded by Kepler did not show a precursor outburst and the superhumps developed only after the maximum light, a first example in the Kepler data so far. Such a superoutburst is understood within the thermal-tidal instability model. The observation of V585 Lyr made the first clear Kepler detection of the positive period derivative commonly seen in the stage B superhumps in dwarf novae with short orbital periods. In all objects, there was no strong signature of a transition to the dominating stream impact-type component of superhumps, suggesting that there is no strong indication of an enhanced mass-transfer following the superoutburst. We have determined the orbital period of V516 Lyr to be 0.083999(8) d. In V516 Lyr, some of outbursts were double outbursts in a various degree. The preceding outburst in the double outburst was of the inside-out nature while the following one was of the outside-in nature. One of superoutbursts in V516 Lyr was preceded by a double precursor. The preceding precursor failed to trigger a superoutburst and the following precursor triggered a superoutburst by developing positive superhumps.
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