Sportiff style bikes are designed for long endurance rides so come with a higher head tube.
Road bike standover.
Stand over the frame in the center with your feet flat on the floor.
If your inseam measurement clears the frame s standover by a bit say at least 2 3cm for a road bike and a bit more for a mountain bike then you should be ok.
There you ve got a frame that should fit pretty close.
Compact style frames have low standover but the headtube is roughly the same as a trad bike style.
Here s how to measure.
If the bike has a sloping top tube semi compact or compact design expect to have clearance of 2 or more.
The bike s actual standover height is the the middle of the top tube.
And swapping out for 27 5 tires seems to be a popular change mountain bike modification.
You will want at least one inch for a road bike and two inches for a mountain bike.
If the bike has a traditional straight top tube that is parallel to the ground you should have approximately 1 of clearance between the ground and tires when you lift the bike as you re straddling it.
Just like your pants inseam off the ground increases with platform shoes your bike s standover height will increase if you add bigger tires.