This looks perfectly normal. They will straighten out when as they mature.

The emerging fronds look normal to me. The older leaves do have some damage on their tips which can be caused by anything, but overall your plant definitely looks healthy. I would wait and see how this new flush of fronds mature and if you still have the same problem, or if the problem worsens, then you know that you have an issue. It could be a nutrient deficiency that was present before you fertilized. Old fronds that have damage will not improve no matter what you do, but new fronds should look better if the problem is fixed.

Good luck!
-Alex

Thanks for the replies guys. I will keep you posted and update more pics as the fronds mature.

Most Cycas species flush with new leaves curled like that.

Ok so here's an update on one of them. It doesn't look too good. :/

Well, no, that is not normal in the least.what kind of pesticides were used and how were they applied? Fertilizer and application?

I used a mixture of different pesticides, namely of termites and caterpillars. Their solution was sprayed onto the leaves and the trunk. As for fertilizers, Ive applied both organic fertilizers (compost, manure etc etc) and a balanced npk fertilizer ( probably 8-8-8)

If you sprayed pesticide on the emerging leaves that is most likely the culprit.
Sago leaves are tough as nails,except when they are still soft/new.

It is possible it is the fertilizer as this can happen but I have bombed mine
with super high doses of grass fert(high N, 21-1-3) and never observed this,not to rule it out but I would say less likely.

So-this flush will be a dud,keep an eye on the plant(Caudex)though,just to be sure there isn't some hidden cause below.

How can I check for rot? And if it is rot, how can I cure it? Could overwatering be the issue?

In that last photo is does look like rot. You should be able to see down in there if you have a growth point or just black mush. The first photo defnitely looks healthy. Are they the same plant?

If the top is rotted revolutas do put out side shoots/pups, so the plant isn't necessarily lost. Don't know what your climate is or whether that could have had something to do with it.

The last photo is from a different plant. The growth point is still there, and there isnt any black mush, but I will keep checking. I will keep you updated. Btw what causes rot?