Morph III Trail and Head Tube Angles - Online Design Session Screen Images

Online design session April 10, 2009 with Alan Ball, Rory McCarthy, and Bill Warner.

 The model shown here is basic geometry from the Morph III design.

 The goal of the meeting was to see if we can pick a geometry that gives us zero or close to zero trail in the high rider mode, and around 2" trail in the low rider mode

Version 1: .92 negative trail in upper mode. Steep head tube angle (measurement not shown

Version 1a: .Range of head tube angles available in upper mode where trail would be zero.

Version 2: 2" Trail in low rider mode. 10.21 fork length.

Version 2: 1.21" trail in high rider with 10.21 fork. Note that head tube is steep (not measured here)

Version 3: 2.03" trail in low rider. 35 degree head tube angle is still steep.

Version 3 Added pedals to the model, and pedal offset from steering tube angle.

Bobby Hall looks like 27 degrees head tube angle, measuring from this photo by Rory.

Version 4: 1.90 Low rider trail, 11.21 fork, 27 degree head tube angle like the Bobby Hall.

Version 4: High Rider, with 1.34 negative trail (may be too much)
Shorten the 11.21 dimension to 10.7 to reduce trail in upper mode:

Version 5: High rider with .95 negative trail

Closeup: We adjusted the fork length as the easiest way to affect trail.

Version 5: Now 2.6" trail in low rider mode. 27 degree head tube angle.

Version 6: Drop trail to almost zero in high rider: trail .18"

Version 6: Low Rider trail becomes 3.96". Too high. Version 5 looks like a good solution.