Wednesday, June 27, 2012
The geometry and wheel base, seat, rail height, etc. are almost identical to a 1970 triumph as are most flattrack frames (champion, trackmaster, redline) so nothing new in that department..... but those frames were designed for the old 650/750 twins - a much smaller lighter engine. Since the new bonnie motor is much larger and heavier I had to lower and move the engine back in order to keep everything in balance. As for the materials the entire frame is constructed from 4130 chromoly steel DOM tubing and bronze (actually silver, nickle, and bronze) welded. A process similar to brazing that uses slightly more heat but not enough to alter the integrity of the tubing which is important because as with all frames that I construct torsion or "spring" is of grave importance. By torsion built I mean the tubing is cold bent 5 degrees off then mechanically pulled into place on the frame fixture. This gives the frame pre-load.....after all pre-load is the divining factor of the frame returning to its original position after being flexed say in a slide or landing a jump. I have applied this process to every speedway, motocross, and flattrack chassis that I've constructed for almost two decades with brilliant results. The finish on the frame is nickle plate. I have to take great care in applying this because if any of this corrosive solution seeps into the frame during the application it will rust though in a matter of months.
The tank and seat are one off three layer polyester with a polyurethane liner to insure I can use any go juice I like without risking the dreaded "my gas ate my glass" scenario.....
"I'm not trying to reinvent the wheel...just trying to make it roll a bit faster"