05 XC expert rear suspension
How does the 2005 xc expert rear suspension layout compare to other designs?
If I'm correctly informed, this is a single pivot system, and I have a chance to
purchase on ebay for a good price, also the build spec is pretty good.
Faux Bar Link...similar to single pivot
When Jamis went to seatstay pivots (2003 and before used chainstay "Horst Link" pivots), they became a Faux Bar Link. Many companies like to call their product a Four Bar Link, but only ones with the Horst Links (for 2007, Specialized (who owns the patent), KHS, Ellsworth, and Titus are the most common) are true "Four Bar Links". Otherwise the "Faux Bar Link" bikes (there are lots, including Trek, Kona, Turner (former Four Bar), Ventana (former Four Bar), and Transition) can also be lumped in with "Single Pivots". They obviously have multiple pivots, but they will ACT like a single pivot bike of a similar main pivot location. In fact the seatstay pivots are almost unnecessary as they only rotate a few degrees (several companies including Trek and Fisher have made "faux bar links" w/o the seatstay pivot, just relying on the flex of the seatstay itself). The seatstays mainly drive the shock directly or drive the rocker that drives the shock.
Now, as far as the Jamis, it works pretty standard for a "faux bar link" which I think work pretty well. The main "issue" with a "faux bar link" is that the suspension tends to stiffen under braking. They otherwise are a proven and well liked design.
Seems to me I might have heard something that Specialized bought the patent from Dave Weagle, who currently designs for many companies, primarily Iron Horse. How elusive, and difficult to characterize, was the inspiration (s) for various rear suspension designs, and what a lot of work for attorneys!