Using plotyy my 2nd Y axis is not depending on X axis when I introduce limits to X axis.

I have 2 Y axis (Y1 acceleration and Y2 Velocity), and 1 X axis (time) I am using plotyy to plot 2 curves

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figure(1)

[ax,hlines(1),hlines(2)] = plotyy(t,Acc,t,Ve);

cfig = get(gcf,'color');

pos = [0.1 0.1 0.7 0.8];

offset = pos(3)/5.5;

xlabel('Time (ms)')

xlim([-80 60])

set(ax(1),'YLim',[-80 50])

set(ax(1),'YTick',[-80:20:50])

set(ax(2),'YLim',[-20 45])

set(ax(2),'YTick',[-20:10:45])

grid on

title('Test 01')

ylabel(ax(1),'Acceleration (g)');

ylabel(ax(2),'velocity (km/h)');

axis on

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The problem is my Y2 (Velocity) is not fixed with X axis. When i changed X limit "xlim([-80 60])" to "xlim([-80 20])" the Y2 (velocity) plot remains same size. But I need to zoom it in the particular interval.

Please help me.