Bilkeny Tandem and Leg Extension

BilenkyEd Honton and wife Melodee brought a nicely built and beautifully painted Bilenky Viewpoint tandem adapted from the old Counterpoint Opus configuration, with an upright captain and a recumbent stoker seated in front over the front wheel. In order to have handlebar clearance and keep the stoker from being suspended too far out front, it uses indirect steering by a short link.

To make transporting it a little easier it has a folding front boom, and for serious traveling it also had several S&S couplings so the frame could be disassembled. The stoker has their own freewheel in the intermediate drive, and also their own derailleur to adjust cadence relative to the captain.

Bilenky2They had some problem with thigh interference with the original front web seat base, so they folded it over double to make it shorter and farther back, which worked out pretty well.

In the Photo at left you can see that Melodee’s thigh is well below the seat frame. Part of the problem is that the base is too long, and doesn’t curve down at the front.

However, a bigger issue is that if the bike was properly adjusted to fit her, her thigh would not be angled downward (at least not to such an extent). As you can see she is as badly overextended as a non-mutant would be trying to ride a bike set up for Jeffie or Tall Dave. Her right leg is nearly straight, instead of having the recommended 32-35 degree bend at full extension. AND her toes are pointed forward, which is not only inefficient but can lead to shin splints. And, she’s not quite bottomed out yet.

Moving the BB back an inch or 2 would help the extension problem but create another. Her left leg is already bent about as far as you would want. Much more would invite knee trouble. Moving the BB back would make that worse. The problem is that her cranks are much too long for her leg length. M.S.