Ok, so I admit this is my first IRS quad... It's great but on gravel roads when going over 40mph, it seems to want to sway from side to side.. the feeling is uneasy to me.

I am guessing it has to do with the IRS?

The only adjustments I've done is adjust the toe out from stock (it's like 2 inches or something!) to about 1/4 inch toe out. Would this make it worse? It made it steer a lot easier... but maybe it makes it more uneasy on gravel? Tar seems fine, even at high speeds.

 

play with the air in the tires. i have felt the swaying once in a while when going about 50-55 and adding or taking air seemed to fix it for me.

 

I agree with kford. Start with the easiest change first, tire pressure.

But first, make sure your toe-in is at stock specs.