215 is the tread width in mm. 65 is 65% of that in side wall height , 65% of 215 vs. 60% of 225 , doable ,
The replacement tire is a bit taller, but not enough to affect the speedometer, braking, or ride. But the proposed tread width is nearly a half inch narrower and this probably isn't something you should do. You'll reduce traction when accelerating, and this will have a negative affect on braking: not a good idea.
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