The reason why the trains can't go faster than 110kmph is because the railway tracks at Sahibganj loop line are inadequate. Another thing is that the railway intentionally slows down the trains at every major station so that they can make up for any delays caused by the trains themselves. If you want to speed up the trains, then wait for the improvement of tracks for 130kmph, only then can speed be possible.

Iska karan Sahibganj loop line mein railway tracks ki anupayuktata hai. Isliye ab tak MPS keval 110kmph hai. Aur slack ke baare mein dusri baat yeh hai ki railway har bade station par trainon ko dheela deta hai taaki trainon dwara ho rahi deri ko pura kar sake. Aur trainon ko tez karne ke liye, 130kmph ke liye tracks ka sudhar hone ka intezaar karen, tabhi teji sambhav hai.