SDG (speed defiys gravity)spelling??They are a brand of bike that come out a couple years back bout same time as thumpstars.A 110 3 valve had lots of probs.
the old 110cc 3valve bikes they made were exactly the same as the old 110 motoverts, except they were askin bout $3900 for it or sumtin. all there parts are still chinese made parts, but are still pretty good.