About anything you like in the 120 size. Another choice is building from plans. I'm presently building the Prime Cut +20 from Airage plans, the plans are the best I have ever gotten from them. CAD drawn and everything fits, makes for an easy build. This is a 40 to 50cc size plane but the plans can be reduced by Kinko's for a smaller engine. Once we can post photos again on RCU I will start a build thread to show how easy this plane is to construct.