New carb, low power? no top end? help!

So I have a 1998 Grizzly 600. Just did a pretty large maintenance on it (I think at least).

including, a brand new carb, new gas, new spark plug, etc etc…

So I decided to take it out for a spin, and it SEEMS to idle just fine, and it runs just fine in low and high gear and reverse etc..

BUT it doesn’t seem to have a top end, if i’m in "high" and I full throttle it, it powers up just fine..but I can barely spin the tires. and in "high" I would say the top speed is…maybe 30mpg..

things it might be: maybe my new thottle cable needs adjusting? I’m not sure..

One other thing to note: I am installing a snorkel on it, using 2" ID tubing, and its currenlty 2-2.5ft long with 1 90degree turn.
From all the reading I’ve been doing on snorkeling it, that SHOULDN’T be a issue…but thought I’d mention it.

So… suggestions? 😀