Rear Axle - tough pedaling

[Sixtoejoe]

I removed my rear wheels on my single drive ancient Miami Sun trike, right rear bolts to bearing, left wheel has a nut on end of shaft ... I had the wheels trued, and tubes and tires replaced ... tires are .25 wider than original. Now when I try to ride it is quite a bit harder to pedal. Is there a proper tightness for the rear wheel axle nut ? or is the wider tire the culprit ? I just assume I did something slightly wrong ... Thanks