[January 29 From Graham Butler]I talked to Bill earlier in the week about the possibility of using elastomers to create a variable force adjuster for the gas shock. I have been thinking about this idea, but I have been having trouble figuring out the geometry. The reason: For it to work well you need 2 converging points on the frame where the maximum lift happens in the low rider position. There are lots of points where you get some lift in low rider position, and then progressively more lift as you morph up. Lets discuss these tomorrow. I also did a bit of research into gas shocks. It turns out that the compressed Argon that I use for welding has almost the a similar individual gas constant as nitrogen (29kg/kg mole for Argon as opposed to 28 for Nitrogen) Both N and Ar are readily available and relatively cheap (nitrogen is used for laser cutting). It comes in a cylinder compressed to 2000psi. If you were to fill this shock with either gas at 2000psi , it would generate ~1700 lbs of force. This begs the question. Why not create a method to fill and bleed the piston. This solves our variable weight problem especially if it can be done on the fly. You could even have a small canister of gas on the bike permanently linked up to adjust the pressure in the piston. Inert gas is relatively cheap....
[January 29, 2010] From Graham Butler:
[Fram Alan Ball January 19, 2010]
We talked about a footrest design that would be from carbon fiber, and woudl also serve as a guard - the bike hits walls often.
David Hansen on Morph 2.5
Knee and foot support idea.
Arc of legs.
Carbon fiber footrest idea
Carbon fiber footrest idea
Extending the seat pan.
Before we go into detailed design for the actual Morph 4 prototype, I asked Alan to check the key dimensions of Morph 4 against those for Morph 2. Everything looks good in the drawing above.Trail in Low Rider: 2.5" (okay, a bit more trail than Morph 2's 1.3")
Trail in High Rider: -1.3" (same as Morph 2) Wheelbase High Rider: 42.46 inches (1/2" more than Morph 2)
Wheelbase Low Rider: 59.37 inches (3/4" more than Morph 2) Height to seat joint, low rider: 9.83 inches vs 12.03 Morph 2
Height to seat joint, high rider: 23.67 inches (.4 inches higher than Morph 2)
Seat height delta: 13.84 inches (2.63 more than Morph 2...very important for low CG in low rider)
Eye height delta: 16.21 inches (extra is due to change in seat back tilt?)
These are the measurements for Morph 2. Note that Morph 2 doesn't have the automatic seat adjustment system, and that it doesn't come down as far.All of these dimensions and angles look good. Nice drawings, Alan. Very clear and simple.