Question about PNF's bike

Triathlon Forum
1

For Slowman or some of the other ‘experts’, what was the theory behind PNF’s 24" wheels? Just curious.

2

I know of three possible reasons.

  1. The geometry of the bike means smaller wheels have a better fit for the handeling of the bike.Dont knwo her size though.
  2. Better aerodynamics was the thought at the time (bc of the spoke speeed and overall size of the wheel.)
  3. Lower rolling resistance bc the angle of attack is lower. (think the opposite arguement for 29’s being better for mtb’s.
3

I think RR is higher because of the smaller tire circumference
.

4

I forgot, Jack is right but I think it may be from the bearings moving at a higher speed and the contact/peel of the tire touching and coming off the road together that would make it so. Again back then people thought very different things as you can even see today with water placement and whatnot

5

What about her double-jointed crankarms? Anyone know the theory with those?

6

As I recall the theory with the “drop cranks” as they were called was that during the downstroke you tipped the lower portion forward, giving you more leverage, in effect a longer crankarm during the power phase. They did give a wider Q Factor, but supposedly she preferred this.

Kevin

7

For Slowman or some of the other ‘experts’, what was the theory behind PNF’s 24" wheels? Just curious.
At the time we all thought smaller wheels meant better aerodynamics (smaller profile). Steve Hed even had a prototype with 16" wheels one year ('89 I think) at the Lake Nikomas Tri…then the wind tunnel proved us wrong.

As for the drop cranks, the idea is that it changes the effective crank length as you pedal (shorter at the top of the stroke, longer on the 2nd 1/2 of the downstroke). Cycling shoes/pedals have the opposite effect, which is why they all look to minimize the sole thickness and “cleat to spindle” distance. PNF’s custom drop cranks had a weight and q-factor penalty, but I’m guessing she felt it was worth it.