I’ve been working on a frame design and would like to get some
collaboration going to either refine it or junk it and start in another
There’s a jpeg of it at my novice web page:
The one I have really been working on is the aluminum I-Beam design. So
far it is at 745 grams. If anyone is interested in seeing it better, a
viewer can be sent out with it so that you can rotate and zoom.
The I-beam style was chosen because of trying to balance the high loads of
the frame with being lightweight. I-beam technology is a very proven type
of construction. the inside profile can be conformed to a specific
If the design is refined in aluminum, then it could be converted to carbon
fiber for even less weight.
The load directions that were considered were imagined being input thru
the seat and resulting in bending, twisting, etc. of the frame. Forces
thru the axle/bearings would be the opposing forces.
Seat loads: Vertical (up, down) Lateral (left, right) In-Line (fore, aft)
Pitch (up, down) Roll (left, right) Yaw (cw, ccw)
Besides the vertical down load, I believe the next greatest load is
lateral that would push the frame into the tire. These two loads should be
far greater than any others. That is the reason behind the I-beam versus
The disadvantage is the possibility of hitting the geometry with a knee.
For this reason, the frame is tapered in and very narrow at this point.
Any feedback would be appreciated
Doug Massey Norman, Oklahoma