Let Shiva's monthly salary be $x$.

He gave $40%$ of his salary to his mother:
Amount to mother $= 40%$ of $x = 0.40x$.

Remaining salary after giving to mother:
$= x - 0.40x = 0.60x$.

From this remaining $0.60x$:
He used $7%$ for electronic gadgets:
Amount for gadgets $= 7%$ of $0.60x = 0.07 \times 0.60x = 0.042x$.

He kept $23%$ for monthly expenses:
Amount for expenses $= 23%$ of $0.60x = 0.23 \times 0.60x = 0.138x$.

Total used from the remaining on gadgets and expenses:
$0.042x + 0.138x = 0.18x$.

So the amount transferred to his friend's account:
$= 0.60x - 0.18x = 0.42x$.

Now, sum of the amount given to his mother and transferred to his friend is given as $41000$:
Amount to mother $+ $ amount to friend $= 0.40x + 0.42x = 0.82x$.
So,
$0.82x = 41000$
$x = \dfrac{41000}{0.82} = 50000$.

Therefore, Shiva's monthly salary is 50000.