I just noted that the BUB site has uploaded a revised rule book.
http://www.speedtrialsbybub.com/2014_event/AMA-BUB-SR-2014-v2.pdfI have not seen all the changes but the "A" special construction class has additional requirements that appear to make it easier for OEM frames to qualify for the "A" class. Here is a section from the rule book:
The use of an O.E.M. frame in the Special construction class must have a minimum of two of the following.
- 2 engines with a combined displacement not to exceed 3000cc.
- Seat base is lower than an imaginary line drawn between the tops of the rims.
- Engine and Frame are from different manufacturers.
- Altered steering head angle.
- Altered Main Frame engine/transmission mounts and tubes. The main frame is defined as the connection from the steering neck to the engine mounts and swing arm pivots.
- Non O.E.M. fuel tank not using the O.E.M. mounting points.
- Center hub steering.
- Wheelbase exceeding factory O.E.M. dimensions by more than +10%. Measurement will be taken at the most forward axle setting. It shall be the participant’s responsibility to provide proper documentation listing specifications.[/li][/list]
Thank you Rex, Drew, and all others who helped to clarify this area.
Don