This is only my personal opinion based on small engine repair over many years.--- When purchasing a Leaf Blower, or String Trimmer, just to name two---notice where the starting cord is located. Many lower priced units have crank bearings on one side of the crank. The other end can have the carburetor attached or it will have a solid plate. An engine with this design is much cheater to manufacture then one with crank bearings on both sides of the crank shaft throw. The good thing about this design is that the rod can simply be removed without pressing the crank apart, as with double bearings. I mentioned "starting cord" because with a double bearing crankshaft engine, it is licated on the outside end of the engine. An example would be a string trimmer---start cord will be located on the same end of the engine as the shaft (between engine and shaft) on the lower priced units. I only have double bearing units because I have found that they vibrate less and thus seldom have an engine oil leak. I have owned a few lower priced units and had good success but the vibration required perodic tightening of all attaching screws. I am only giving advise based on my experience and others may disagree.