On Monday, August 7, 2017 at 7:43:38 PM UTC-7, John B. wrote:
On Mon, 7 Aug 2017 13:33:40 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 5:55:16 PM UTC-7, John B. wrote:
On Sun, 6 Aug 2017 08:13:39 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 8:05:51 AM UTC-7, wrote:
On Saturday, August 5, 2017 at 6:47:46 PM UTC-7, John B. wrote:
On Sat, 5 Aug 2017 11:57:18 -0700 (PDT), wrote:

We've probably argued about this before but since I can't remember crap I can get clean opinions.

I presently ride 175 mm length crank arms. I have problems spinning and watching the Tour this year what was clear was that there are no more luggers in the peleton. This suggests that spinning is the way to go.

So: Has anyone experimented with different crank arm lengths and have they been able to tell the difference between one size different in length?

Years ago I conducted a personal test of spinning versus lugging (as
you call it) I rode 50km out, on a 100 km route, lugging and the
returning 50 km spinning. The second half was definitely faster.
Terrain in that case was pretty much the same in the two parts of the
test.

Currently I keep, on Phuket Island where the above test was conducted,
a road bike, currently with 170mm cranks, and a utility" bike with
175mm cranks. While most of the utility rides are in the local area I
do a 20km ride on it, usually once a week.

I can't tell the difference between 170 and 175mm cranks. In fact the
road bike originally had a mountain bike triple chain wheel set with
175mm cranks. When I changed it to a road bike triple with 170mm
cranks I never noticed the difference.

On the other hand spinning is probably not instinctive and lugging (I
prefer the verb "Mashing :-) probably is so you need to work at it a
little before it becomes instinctive.

The Pros spin at pretty high rates, Froome was said to be spinning
nearly 100rpm going up hill, but that probably isn't practical for the
average rider.

Initially, try riding, on level ground, and spinning at say 90 rpm, in
a lower gear ratio. When spinning begins to feel natural up the spin
to 100 rpm. I think that you will find it becoming natural after a
while.

Initially the secret is to use a lower gear ratio. 80 rpm in a 50 - 18
gear results in ~27 kph. 100 rpm in a 50 - 23 gear results in ~27 kph.

I think that I would like a 50-11 top gear and a 34-28 bottom. This should give me everything I have with the triple except the bottom 2 gears which I never use (well, once up a 30% grade - how common are those?)

By the way John - thanks for the information and I'll be sure and let you know the results of the experiment.

I might mention that when I first tried spinning that I seemed to
bounce in the saddle. It takes a little practice.

I pedal circles so I don't bounce.

You'd be surprised. Get a tachometer and see how high you can go
without bouncing :-)

Right now I'm just returning to condition but last year at this time I could accelerate through yellow lights up to 32 mph in third gear without bouncing. This was a 52/15. In a 52/12 I could ride for four or five miles at 28 mph.

In the first case that's 116 rpm without bouncing.