Here's another option...

DECLARE @StartTime1 TIME = '17:41:00.0000000';

DECLARE @StartTime2 DATETIME = '2016-09-22 17:41:14.810';

if @StartTime1 = CAST(DATEADD(mi, DATEDIFF(mi, 0, @StartTime2), 0) AS TIME)

select 'Times match'

else

select 'Times do not match';