If you want to avoid the safety checks just claim that you made it over 10 years ago or write a declaration that it is intended for disabled use. Research MSVA exemptions and you'll see what I mean. You then fill in form v55 stating your exception to MSVA. Then you need insurance, MOT the list goes on...
By the way, if you have a 65/70cc chinese engine just create a plate stating that the capacity is 32cc to get away with registering as a moped.
We should really start a petition to legalise motorized bikes in the U.K
BSA