There are a few things that will come into play.

First of 11 lbs of thrust on a 22 lb model will not produce an aggresive climb. But it will rotate and lift off.

At 7500 rpm and a 6 inch prop pitch the pitch speed is going to be 42 mph. Now this is only approximate since the engine may well unload in the air to a higher RPM and allow for a little more speed. But it's a decent enough number for consideration. So the prop is basically only going to accelerate the model UP TO 42'ish mph. That's all well and good if the stall speed is 25 mph. But if the stall speed is up around the mid to high 30's then there isn't a wide operating envelope. You may well find that the performance in the air would be better with a prop that has an 8 or 9 inch pitch and corresponding smaller diameter which still allows the engine to reach it's peak HP RMP. For example at the same 7500 rpm an 8 inch pitch prop would have a pitch speed of around 57 mph. That seems like a far nicer speed for your model to have as a max level speed. It will make takeoffs a little slower and longer and you'll need to watch the climb angle but once up to some altitude and at level the airspeed would be much nicer to work with. So some prop testing would seem to be in order.

You can also get an estimate on the stall speed by using Foilsim over at;
http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.html

Input the numbers for the wing span and average chord and set the angle of attack to 7 degrees. Set the airfoil thickness and camber to closely simulate what your model's airfoil is like. Then lower the airspeed until you reach 22 lbs of lift. The airspeed that this occurs at will be a pretty good approximation of what your model will stall at. Hopefully it's down somewhere in the mid to high 20's. The less the better obviously.