I have a 72 Citabria w/ O-235 and wood spars. When I get up to cruise, over 90 MPH or higher, Ailerons get Extremely Stiff. They go from about 5 lbs of pressure to move the stick right or left at below 90 mph, to about 20 lbs of force at higher speeds. Really a drastic change. I know it should get harder the faster you go, but this is not right!!! Any ideas? Rigging? Drag/Anti Drag Wires letting wing move in higher speed flight? Max speed in level flight is 110 mph @ wide open (2600 RPM) and only when I lean it aggressively.