If an EV trained Pokemon evolves,do its EVs get transferred to the evovled Pokemon?

Question

I gave 252 speed EVs to my litwick that had a speed increasing nature and as soon as it evolved into lampent I used a dusk stone on it to evolve it into chandelure.When it was lvl50,it had 137 speed.It says on Bulbapedia that it should have 145 speed at lvl50.

But when I gave 252 evs to my gyarados that had a speed increasing nature,it had 145 speed at lvl50(only 1 point less!!!)

So my question is,why does chandelure have 137 speed at lvl 50 instead of 145?

The same thing happened to my conkeldurr

Answer 1

EVs remain there throughout evolution
In regards to why you're at less than what should be your speed stat, I say it's because of your IVs.
A Gyarados with a speed IV of 30 with 252 Spe EVs and a positive nature at level 50 has 145 speed,
Similarly, with your Chandelure it seems to have a speed IV of 18

Alternatively you didn't get 252 EVs onto it. :P