Yep, I am fully aware of the rich low end needle setting. It has a great idle and good transition from low to high and from high to low... The only thing is it vibrates pretty bad throughout the whole rpm range... It's not the shaking at low rpm i'm worrid about its the vibrations... There isnt an engine box per-say... All it has is a firewall... Check out Tower Hobbies and look at the Reactor 50cc and you can download the manual... The way they have it set up in the manual is exactly how I have it set up... The stand off distance is 3"... And everything looks to be pretty solid up front and no where close to being loose... Also, all bolts are RED LOCKTITEed...