"Hossack Suspension" for Lego BMW K1300S

[DLuders]

On the TRX Project website, somebody created a motorcycle's "Hossack suspension" with Lego Technic parts. BMW uses this suspension (also known as "Duolever") for their K1300S motorcycles. "DrSlumper" wrote,

"This suspension system is geometrically is a double wishbone system in wich the steering and suspension are both independent where the shock damper and the suspension links are not steered and the steering parts are not under efforts."

There are 12 pictures of the motorcycle on DrSlumper's Picasa gallery.

[Front]

Very nice.

I made something similar a year ago, and have a topic on it:

MOC: Technic Motorcycle

Edited October 14, 2010 by Front

[Front]

Hey wait.

Actually I don't think the suspension works on the TRXProject bike, without slight strain on the parts.

This is due to the fact that the revolution axis of the steering bar and the axis of the fork (through the two wishbone balls) is not colinear for every value of suspension-travel. Because of this a ball joint is needed where the two yellow links are jointed. On the real bike I think the joint is a revolution joint which allows for small misalignments in the revolution joint.

[TechnicJuan]

With no disrespect to the original designer, That suspension seems rather flimsy. Especially with those old school angle connectors. Unless it is actually just more for "Show"

[Marcos Armero]

Hi to all, I´m Marcos Armero (the blogger of The TRX project), First congratulations to Front for this model, what a great job!!. Thanks TechnicJuan for your reply, and both (Front and TechnicJuan) have the reason on your replies. To be truth my Hossack suspension model sucks (much more after view the Erland model). I made it with my Technic parts that survived this last 15 years. Some times I "play" with my technic parts but not allways I can do all that I want, I need to buy new lego parts.

Congratulations to Front for your model, I published some pics and links about your Hossack motorcycle on my blog (http://thetrxproject.blogspot.com/2010/10/lego-technic-hossack-bike.html) because I really like your MOC.

Greetings from Spain.