On 2016-08-30 20:22, Frank Krygowski wrote:
On 8/30/2016 10:35 AM, Joerg wrote:
On 2016-07-19 10:36, Frank Krygowski wrote:
My wife's favorite bike, her Cannondale touring bike, is becoming
unusable for her. Due to stiffness in her hips, she's becoming unable
to swing her leg over the saddle in its normal position. The frame is
not a step-through design like a mixte or "girl's bike," although the
top tube is much lower than typical.

I thought I might solve the problem with an ancient Hite Rite spring and
quick release unit
https://i0.wp.com/oi50.tinypic.com/124zyhi.jpg
so she could come to a stop, then lower the saddle before swinging her
leg over. But the seatpost motion is far too stiff. Despite several
hours of effort to be sure there are no burrs, despite trying different
lubricants, etc., the seatpost doesn't easily drop under her weight.

I can try to locate a much softer spring, I suppose. But I wonder if
anyone has come up with another solution, other than a
multi-hundred-dollar dropper seatpost, or a new bike. Ideas, anyone?


Just curious, what did you finally end up installing?

Here's how that settled out, so far: First, she's been mostly riding
the tandem, so it's been less of an issue.

But for the bike in question, the short version is, I found and modified
a long spring to use as a compression spring inside the seatpost and
seat tube. Dowels at each end of the spring fine-tuned its length. It's
much softer than the Hite Rite spring. I used a quick release lever in
place of the frames original hex seat clamp. I also spent time
polishing and deburring the inside of the seat tube.


So you built the Krygowski seat dropper :-)


So, she has the option of coming to a stop with her weight partly on the
saddle, loosening the QR lever and having the saddle sink, then clamping
it again. That gives her more room to swing her leg for dismounting.
The fine-tuned length puts the saddle back up at proper height when
there's no weight on it.

As one might expect, she decided that was too much trouble and, as
several people advised, has been tilting the bike way over for
dismounting. :-/ But the mechanisms there if she needs to use it.


Maybe put a real seat dropper for downhill MTB riders on your long term
watch list, see if one goes on sale. The advantage of that is that you
do not need to re-align the seat for exact forward pointing. The good
ones even have quick-action levers which you can mount to the handlebar
or some other convenient place.

--
Regards, Joerg

http://www.analogconsultants.com/