brake lines

hi guys ,
iam new to power kiting and im hooked on this sport. could i ask this question i have a beamer II 2.5 and a Beamer II 5.0 the 2.5 flys great in all wind conditions but the 5.0 can be a bit tempremental . i have only took this whale out in light winds as i am still on a
big learning curvre how do the brake lines affect the flight of power kites E.G. the adjustment as the 5.0 kite seems to spiral alot and i move the line from to 3 knots to 2 knots and it flys better but i loose the feel of the break lines ( harder to land the kite ) could you shead some light on this for me or how to stop sprialing on take off . idont have this problem on the 2.5 .

thanks in advance mark (Rickenma) :puzzled::puzzled: