my1020 750w compared to my1020 1000w

hi there i have two motor witch i use both to test,1 is a unite 750w 36v blue motor rated at 2800 rpm,and a my1020 1000w 36v black motor rated at 3000rpm,my question is the following,why is my bike slower whit the 1000w motor ?is dose have more toque but its slower on top end even if it stats 200 more rpm than the 750w motor...
i used the same gear and state of charge,

best regard