Re: Getting old is not for sissies

On 3/1/2025 4:39 PM, Jeff Liebermann wrote:

On Sat, 1 Mar 2025 13:55:50 -0500, Frank Krygowski
<frkrygow@sbcglobal.net> wrote:
 

On 3/1/2025 1:22 PM, Jeff Liebermann wrote:

On Sat, 1 Mar 2025 07:43:22 -0600, AMuzi <am@yellowjersey.org> wrote:
>

On 2/28/2025 5:52 PM, Catrike Ryder wrote:

I was thinking about fixies just the other day on my ride and thought
maybe I could set up a fixie on the Catrike. Then I considered how
often I coast. Keeping my legs moving the whole ride is not something
I want to do.
>

>

I thought about your comment this morning.
>
While almost everything humans can imagine is possible when
time and money have no value, there's no practical
straightforward way to make a Catrike fixed gear.

>
Hardly straightforward, but certainly possible.  Remove the gears,
chain and sprockets and replace them with a hydraulic gear pump, two
hydraulic hoses, and a hydraulic motor on the wheels.  This is nothing
new.  There are motor vehicles and construction equipment that use a
hydraulic pump at the engine, T junction, and a hydraulic motor on
each wheel.

 

IIRC, hydrostatic transmissions are standard features on zero turn
mowers. But as you noted, the mechanical efficiency is lousy. That's not
a concern if you have a big enough engine and low enough use hours. It's
a huge concern for a cyclist.

 True, but the huge concern is mostly for racing.  If you're using the
bicycle as a moving exercise machine, the added weight and increased
friction might even be considered beneficial.  It's like the weights
on barbells where light weight is not a concern.  For competitive
fixie racing, maybe the governing organization should specify a
minimum allowable bicycle weight, which might inspire technical
innovation instead of shaving grams off the bicycle weight.

The UCI weight limit of 6.8 Kg applies to all types of bikes, track bikes (aka fixies) included
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