Need advice on cargo bike steering geometry

[JuanGrande]

Steve, thanks again for the link. A quick question - in you experience, have you built a single pivot trike (i.e. instead of the trike front wheels both rotating, the entire front end assembly, wheels included, rotate around a single pivot point)? The reason I ask is that I am struggling with how to apply the "Ackerman" principle or some of the other aspects discussed in the video when the wheels don't turn individually, the entire front assembly turns. That's why I was wondering if aspects like headtube angle, and fork rake might apply more to this design. In doing my initial research on which approach to use, I knew that corning and higher speed stability were issues. Intuitively, the only thing that I can think of to help this would be some sort of dampener to address bump steer issues.

That said, I think for a cargo bike that will be used for city streets, I will try and adopt to a different front end design to allow for better handling and try and reconfigure how the cargo is carried.

Jonathan

[steve garro]

Steve, thanks again for the link. A quick question - in you experience, have you built a single pivot trike (i.e. instead of the trike front wheels both rotating, the entire front end assembly, wheels included, rotate around a single pivot point)? The reason I ask is that I am struggling with how to apply the "Ackerman" principle or some of the other aspects discussed in the video when the wheels don't turn individually, the entire front assembly turns. That's why I was wondering if aspects like headtube angle, and fork rake might apply more to this design. In doing my initial research on which approach to use, I knew that corning and higher speed stability were issues. Intuitively, the only thing that I can think of to help this would be some sort of dampener to address bump steer issues.

That said, I think for a cargo bike that will be used for city streets, I will try and adopt to a different front end design to allow for better handling and try and reconfigure how the cargo is carried.

Jonathan

no, I have not. Man - mine slides turns FAST! Keeping the load low seems to be key.
As you pivot your Ackerman will change, causing the wheels to scrub even more, I would think - the inside wheel would be on a much tighter track......
I think you need to think more about KING PIN INCLINATION instead of rake/trail........as it is your current design your contact patch of the tire is right at the bottom {or, just in front of it, actually} so it's inclination to ride over a bump would be comprimised...
Great topic! - Garro.