Max insertion point for handlebar stem

[madcyclist]

how can we find maximum insertion point of handle bar stem. In other words how to check how much stem can be inserted in the head tube.
my bike is hero hawk-nuage

[nfmisso]

Generally, the handle bar stem can be pushed in until it stops hard. Loosen the bolt so that the bars move up and down freely with respect to the frame (on some this may take some forceful encouragement); then push the bars all the way down.

In the other direction, on most bike built in the past 40 years, there is a line for minimal engagement into the head set.