Re: Frame Building questions
Take the welding classes then practice, practice, practice. Building a frame for a motorized bike isn't something for the amateur to take on.
Even if you were a qualified professional welder you need to consider the legal side of building and selling bike frames. Protect yourself from 'personal injury' lawsuits. That might prove harder and more expensive that the actual building of the frames.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"