tomato coupe

Sure, most cyclists do both. But prioritizing torque over cadence is only practical over a fairly narrow range of power.

LarrySellerz

from what I’ve seen, the fast people tend to go for big gears, high torque, on rolling hills. That’s one of the times where you care about getting big power much past your average over an hour. There have been multiple times where I’m falling behind on a hill and people are telling me to shift up.

RChung

I'm not sure "prioritizing" is the right word. I think they're jointly determined, depending on what the rider is facing, and what the rider wants to do. I do think some riders lean a little bit more toward modulating their power with cadence, others lean a little bit more toward torque, but everyone is adjusting both, all the time.

rsbob 

The real joy is getting an unstoppable nose bleed and having to climb a long steep with your heart rate increasing dramatically along with the blood being pumped out of the nose. When I got home with lips, teeth, chin and jersey covered in blood my wife freaked.

I too jive between 82 and 92 outdoors and will shift often to maintain my preferred output. The two exception are when climbing 5%+ when I drop down and when ZWIFTing I can find myself at 105 at times.

choddo

Or for a short period of time because most people go anaerobic doing it.

PeteHski

Yeah I think cadence and torque are both dynamic when the riding situation is dynamic. For example if I attack a short, steep climb I will ramp up both my torque and cadence simultaneously. I might go from 80 to 95+ rpm and then start shifting down gears to maintain that higher cadence. Or I might take a completely different approach and attack it out of the saddle in a higher gear and lower cadence.

Talking about a “preferred” cadence has more meaning for me with steady state power efforts. If I’m doing a 20 min sweet spot interval in ERG mode I will revert to my “preferred” cadence at that constant power. As I mentioned earlier, my “preferred” steady state cadence will tend to creep up at higher power levels. However, for steady state climbing I tend to prefer a slightly lower cadence than on the flat at the same power.

Jughed

I'm just the opposite, and it could be due to the different body types we have, as discussed in other threads.

Plus the limitations of gearing with my power output & weight. My cadence is slowed to a crawl when climbing 7%+ - if I'm grinding up a climb at 220w - I may be turning 70 rpm in my easiest gear. That 220w on the flats can be at just about any combo of torque/cadence.

I find that doing a spirited flat ride, I can vary from 200-300w+ at will without any real sense of blowing up. Staying in the lower range with surges into the higher ranges, even much higher ranges - no real issues.

If I try that when climbing, even minor surges, everything goes to crap.

As for preferred cadence ranges - 87 seems to be my average number, regardless of the ride type (except climbing). Intervals are similar to others here - threshold 85-92, VO2 92-100 - peak sprint power comes in at 120.

PeteHski

I think that applies to everyone once the going gets steep. Once you have run out of gears, cadence is whatever it takes to keep moving forward. The concept of a “preferred” or “optimal” cadence becomes meaningless.

For me that point is around 8-9% slope for a prolonged road climb, which makes me think that I could be more efficient climbing with a lower gear range. I currently have a 35/33 low gear, but I would like to try a 33/36. That is going to be one of my winter experiments on my Kickr Bike where I can simulate both ratios back-to-back on a long climb.

chaadster

Oh man, that’s cool! Much more comprehensive and informative compared to the old school gear-inch chart scrutinizing! I should get a smart trainer bike like that…

choddo

needs to be cool at that price

PeteHski

It’s pretty cool. The software has presets for all the major group sets and shift ergonomics. Or you can use custom settings for anything else. I can also adjust crank length from 165-175 mm in 2.5 mm steps. Along with all the QRs for stack, reach and saddle height/setback, it’s like having your own shop fitting bike!

PeteHski

Yeah, quite a big investment, but keeps wear and tear off my bikes. I had a smart trainer previously, but this is better for heavy use. I’ve had it for a couple of years now.

choddo

A mate had one go badly wrong recently but it’s now repaired (for free, wahoo are good for that) and it’s an impressive bit of kit.

RChung

Can you get actual wheel speed, cadence, and power from the Kickr bike in parallel with what Zwift reports? It'd be interesting to see whether the Zwift power model and the Kickr power model align.

PeteHski

I will have a look. I presume the Kickr is broadcasting power and cadence to Zwift at whatever frequency, but I think Zwift has "sticky" Watts if you suddenly stop pedalling ie. it holds your power for a second or two before dropping to zero.

chaadster

You can if the Wahoo app is paired to the bike, and relevant to the thread, it also reports torque, so you can look at the average torque for the entire ride, or specify the period or duration within the ride to see average torque, e.g. from 5min through 60min.

That’s using the Chart slider after selecting Power Summary. There’s also a Power Curve box that offers insights on peak power for preset time periods.

So, for example, on a particular 1.3hr ride where I averaged 191w at 82rpm and 16.4ft-lb torque, I can also see that my peak 10min power was 229w at 83rpm and 19.5ft-lb, peak 2min power during the ride was 271w at 85rpm and 22.5ft-lbs, and my 10sec peak 506w at 81rpm and 44.1ft-lb.

I’m not saying those numbers mean anything, not wven to me, because I don’t monitor torque in particular anymore— I used to, like 10 years ago when using CycleOps PowerAgent software to analyze stationary rides, because it was graphed with the rest of the data— but it is readily available in the Wahoo app if anyone would like to understand how torque, cadence, and power relate.

RChung

This paper's study subjects are world class and elite track athletes (so not really relevant to us) but what's interesting is that "field-derived" (i.e., velodrome) and "laboratory-derived" (i.e, on a stationary bike) cadence and max power were different. This means that the "load characteristics" of the stationary bike and the velodrome track were also different. World-class track athletes are an edge case but it suggests that "freely chosen" cadence and torque may not be directly transferrable between lab to road.

https://www.tandfonline.com/doi/full...4.2023.2288435

PeteHski

That is interesting. In the paper they speculate about the possible effects of the extra mental workload, skill and complexity involved in cycling around a track at 70 kph vs stationary.

chaadster

Relatedly, and perhaps interestingly, the ride data I posted upthread was an outdoor ride, while on Wednesday, I did a stationary ride on the old PowerTap 300Pro (or Pro 300; I forget) and looked at the PowerAgent data, including torque. I was just doing 5min blocks of L3 and L4 (so Tempo and Threshold) alternating cadence from 80-85, 90-95, 85-90rpm and back, so it was easy to see to torque values. As it does, PowerAgent reports in Nm, but I was seeing values like 7.5Nm-8nm (L3 and L4 respectively, ~250w and ~300w) which convert to only around 5.9ft-lbs. It seems either like something is way out of whack in either one or both of the readings, or it's an extreme example of the paradigm proposed in the report.

I didn't have time to dig bag in ancient files from the PowerTap (going back to 2011) to compare torque values, but maybe I'll try to do that some day. I don't have a computer with PowerAgent anymore, but my coach has one in the studio, so it should be possible.

choddo

Is that full rotation average? That's only about 80Watts at 90 cadence unless I've missed something.

RChung

IIRC, PowerAgent reported torque not at the crank but rather reported torque at the hub -- so if you're used to thinking about torque as crank torque, you would need to multiply the hub torque by whatever gear ratio you were using to convert it to the units you're used to seeing. So if you were pedaling, say, a 52x13 gear, you'd need to multiply the hub torque by 52/13 = 4 to get crank torque.

PeteHski

That makes sense of his reported numbers. If the 8 Nm torque was measured at the hub, it would scale to around 30 Nm at the crank, which would equate to a power of around 280 W.

PeteHski

I’ve been off the bike with flu this week, but I did confirm that I can pair my Kickr Bike with the Yahoo app and Zwift simultaneously, So I will record some data over the weekend and see how they compare.

From a very quick test riding for a couple of mins in my flip-flops I can already see that the reported wheel speeds are going to differ by quite some margin in certain situations, especially when descending at high speed. But they look close when riding steady on the flat.

From my quick test on the Yahoo app, it reported 210 W @ 85 rpm and torque 23.5 Nm, which is consistent with the power and cadence. Wheel speed was reported at 30 kph on the flat, which seems slow.

chaadster

ah, well that explains some things! Thanks!

choddo

30kph in the real world at 210W seems maybe a little low but not too far off, 10% at most? Depends on aero profile of course. Can’t remember if the Wahoo app lets you define your height etc.