Hero Honda - Weekly Chart
The weekly charts of Hero Honda shows the obvious resistance at 2100. After failing to clear this level for the third time, the stock has plunged below the previous support. A normal measured move for the above kind of price action would be a move to somewhere around 1100 (the width of the previous price band). If you are an Elliot Wave fan, one can also count clear 5 waves to the highs and the current move is probably C leg or wave 3 to the downside.
So unless there is an immediate reversal with volumes, this might be just the beginning of a bigger fall for the stock. The stock is oversold in the short-term and may see a bounce to 1700's.