What data are you most interested in?
Why off-road? Because you think there are more violent efforts with higher power peaks?
At the moment, I’ve done 2 hilly rides (20km with 350m of d+) in 36” 145mm:
- The first was intense, I gave it my all in every hill (to raise watts and heart rate).
- The second was on a similar route but I tried to keep the cardio low and concentrated on pedaling smoothly.
On both rides, the data on power phases, left/right balance, fluidity and pedaling efficiency were the same on the 2 rides. I was offended to see only 2/3 efficiency and 15% fluidity. 
Probably the sensor considered that I wasn’t in the right gear…
It seems that cyclists have their power peak at 90°, whereas my power peak is around 0°.
My hypothesis is that crank length and schlumpf use should have more impact than focusing on pedaling smoothness.
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Simon,
You measured power on roady and hilly races during Grenoble Unicon which were very interesting, just is missing I guess data during Muni
I’ve done several rides on my G36 with my power sensor pedals.
This morning, I wanted to test the impact on power of the 2 positions I use on my unicycle (upright and aero).
Near where I live, there are some little country roads with little traffic, including 1 loop of 3.5km (with 17m of difference in altitude, mainly on a 1km false flat at 1.5%).
I did a simple protocol with 4 laps:
- laps 1 and 3 in the upright position (hands on the barends)
- laps 2 and 4 in the aero position resting on my aerobars (elbows in the elbow rests).
I tried to be regular in my effort (I put a little more intensity into the first 2 laps). Here’s the data:
I don’t know the formulas for calculating CdA so… I asked chatGPT to estimate my CdA in the 2 positions and the relative and absolute difference in performance of the 2 positions.
ChatGPT estimated that the upright position has a CdA of 0.47 and the aero position a CdA of 0.40.
The AI estimated an aerodynamic drag difference of around 15% and produced this graph:
I’m unable to check the calculations, there may be errors. Finally, the CdA are higher than those estimated by @unicycleharry, there is certainly an overestimate due to the efficiency of the schlumpf hub and the course where there is a bend where I have to brake.
When I had my V-frame built by @jaco_flans , aerodynamics wasn’t my priority at all. It was really about stiffness and comfort. The aerodynamic position was just a side effect. If you compare it with road cyclists, I’m not sure you can say it’s very aerodynamic, but compared with a conventional unicycle, it’s maybe a little better.
I’m keen to continue testing on a more regular circuit, where I plan to attempt a 100km record on May 18.
EDIT : I asked the AI to redo the calculations with a 95% efficient hub and he tells me that in the upright position the CdA is 0.45 and in the aero position the CdA is 0.37. In a more optimal circuit, the difference in aerodynamic drag shouldn’t be far off 20%. It makes me want to learn the formulas and stop asking chatGPT for stupid stuff.
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On mine, I don’t have any power data, so I cannot say for sure how much of an impact the aero position has, but when there is head wind, the difference in feeling is really important.
