New Cannondale Scalpel - Horst link without the pivot?!

[MattyB]

Just saw this on MBR... The new Scalpel XC / Downcountry (WTF does that mean... ) has come out sporting a “Horst-ish” 4-bar linkage. They’ve dispensed with the chainstay pivot completely and done this...

I know Cannondale have often pushed the boundaries in the past (the Lefty for instance), but this scares the *$%# out of me. Would you buy-one given their somewhat infamous “Crack-n-fail” reputation?

 

[MattyB]

Hmmm, doesn’t seem it actually has to flex that much, maybe it would be ok - from around 1m50...

 

[Gary]

it's not a horst design and not even slightly "horstish"
it's nothing new and they're certainly not pushing any boundaries either.
plenty manufacurers have used frame flex instead of a pivot.

Look at the Giant Stance (the budget version of the trance) it uses a similar layout but the flex portion of the frame is in the seat stay and it's aluminium.

Flexpoint Suspension | Giant Bicycles Official site

Using the flexing elements of the rear chainstay and seatstay, FlexPoint Suspension eliminates complex pivots and linkages to provide an effective, lightweight ...

www.giant-bicycles.com

 

[Gary]

remove the shock (or just one shock bolt) from any frame of this design and cycle the bikes suspension through it's swingarm travel. you'll feel it move smoothly through it's initial travel as expected and gradually get stiffer until it passes the point where it the chainstay has to flex most where you'll then feel almost a negative resistance where if feels like it flips into smoother easier movement again.
This isn't all bad so long as the designers got the kinematics and leverage curve right and the shock is appropriate for it.

plusses are it's cheaper to manufacture, lighter and less maintenance.
The drawbacks are fairly obvious.
Suspension performance of an XC bike doesn't have to be next level though.