We just extended them using old pipe, an older kid down the block put a Briggs 3.5 horse in a Schwinn frame chopper, we thought he was so cool. lol That was 1970 or there about.
we made choppers too think around 73
no welding cut the forks and hammered a piece of pipe over the fork then the rest of the fork in the end
we were riding and my buddy swerved into a car .....after a trip to the hospital .a puctured lung ...he came out ok