Thanks for the kind words.....
There don't seem to be too many 4 cycle engines that will fit-it is really tight in there. Clones and some Briggs and Tecumsehs will work if you remove the tank and use a header,but anything over 99cc will be hard to get your right foot around to ride safely. Of course,you could attach new pegs,but in my opinion,that compromises the authenticity of the original design. I did happen to notice that you can put your heels on the front of the frame loop,if you absolutely have to use a bigger engine. This frame was obviously designed to use a 2 cycle,but really good ones are hard to find (at least for me)and I like clones because you just start 'em and go. Flattie Briggs and Tecumsehs have interference issues with the spark plug and frame top tube. That was one reason why the Monster Frijole,like mine, tilts the engine plate 5 degrees. It's a challenge,but that's half the fun........