Is it a good idea to use a lawnmower engine on a go kart.I am building a home made go kart

I have seen it done with a four-cycle Briggs & Stratton type motor. Though, in my opinion you would need to make sure your throttle control works well enough to give you the power output you will need. And the clutch mechanism should also be well thought-out. The one I saw, years ago, had a pulley and belt drive type of clutch mechanism. And it seemed to work well enough because I had a huge headache after bouncing around in it on somewhat rough terrain for about one hour.