Frame Modifcations
In order to have our steering design work, the head angle had to be modified. The figure above depicts the head angle of a bicycle which is the angle between level ground the front fork tube. The head angle was originally 68⁰, and we had it changed to 80⁰. The purpose of this was to have more responsive steering, ad to eliminate the “flop effect” of the front wheel, which caused it to steer on its own due to the weight of the wheel pulling the wheel to one side or the other.
This is where we had removed the front fork tube from the frame in preparation for welding this in at the new desired head angle for steering improvements. After removal of the tube, the frame was leveled and a magnetic angle gage was used to get an accurate cut and placement of the new front fork tube prior to welding.
This is the welding of the new front fork tube to the existing frame using a wire feed gas mig welder. The tube was initially tacked in place and measured again before the final welds were completed.
The final product of the front fork tube welded in place at the desired head angle. The bottom bearing mount is in place for the front fork and the top mount to follow.
A tube in the cross support of the frame was also added for the steering system we are implementing on the jogger. This is so we can utilize the use of handlebars for ease and familiarity due to its similarity to a bicycle. This rear support was bored to fit the rear tube size, and set to the angle we wanted in the same fashion as the front fork tube.
This is the finalized product of our frame modifications, minus paint. As you can see, the front fork tube and rear steering tube are welded in place along the centerline of the jogger at similar angles to keep the frame symmetrical and balanced.