Scotto stated that the Bixby frame is a little smaller in the triangle area than the Slant frame. A preddy 99cc was a tight fit for his daily cruiser in the Bixby. Good luck fitting a 212 in a Bixby.
Just sayn'...
As I stand corrected by Scotto,I can attest that a Felt brand frame will not let you down, The last Felt frame he used (a Slant frame) took a horrible beating and had a terrible death, yet it was still in one piece. Just not the correct shape.