jamesdak 

Well I'm just getting used to my Dutch bike but I will say heading home from the store yesterday I was going into a pretty stiff headwind up a mild grade. Tried going more aero and it felt really awkward and inefficient on the Azor. Going back upright and using the gearing felt much better and seemed to be faster although I have nothing to substantiate that with other then I was able to push a harder gear.


I'm digging this beast while using it within the parameters it's made for.

Moisture

@CrankyOne

Aerodynamics aside, leaning forward will help counteract the rearward biased weight transfer you may experience while accelerating hard or maintaining a good average speed. So, unless you are racing balls to the wall, average semi spirited rider will do best in a neutral position. That doesn't mean fully upright or laying down , just neutral.

Shouldn't you (ideally) keeping most of your weight in the cranks (bottom bracket) and off your bars/saddle?

satrain18

The old man in the Dutch bike was pulled by 200 pound test transparent monofilament fishing line.

CrankyOne

Sorry for the late reply. At higher speeds, yes. At lower speeds no. First, any weight on your handlebars is wasted energy. But we'll get to that in a bit.

Your body is a LOT of weight. Putting all of that weight on to the peddles takes a gob of effort and uses a lot of energy. Yes, it can produce a lot of power but at the cost of a lot of energy. Riding 13 MPH doesn't require that anywhere near that much power. Above about 10 MPH, the higher the speed the less efficient. I require 70 watts to maintain 13 MPH sitting fully upright. If I lean forward and double my speed to 26 (and I have to lean forward and put more of my body weight in to the peddles to go 26) I don't double my wattage to 140w but increase it to 460w. My watts per MPH plummets.

Similarly, if I'm sitting upright riding 13 MPH @ 70w and then I lean forward and put a bunch of upper body weight on the handlebars maintaining the same 13 mph pace I'll see my wattage output go up to nearly 100w. I'm still going 13 mph but I'm using more energy because now I'm using my hands, wrists, arms, shoulders and back to support some of my body weight that previously was supported for free by my very efficiently designed counterbalanced spine. In leaning forward I'm also reducing cooling surface as well as creating folds of skin that become bacteria factories.

GhostRider62

Beautiful bike. Really well made.

CrankyOne

Awesome bike!

My guess is that you were simply leaning forward more than was necessary. I generally have to be going up a pretty good grade or in to a harsh wind to lean forward any noticeable amount. It happens kind of naturally though. You're happily climbing and then you kind of feel yourself leaning forward a bit in to your peddle stroke and then it gets steeper and you lean forward a bit more and soon you realize that it'd be better to put your hands lower near the stem.

I think everyone is also different. I have more fast twitch than slow twitch muscles so I'm more efficient for myself w/ a higher cadence than slower but I think I'm overall lower than average efficiency so I'll use slightly more energy riding 100 miles @ 13 mph than most. I'm more of a Mark Cavendish finishing 40 minutes late than Tadej Pogačar.

PeteHski

That makes sense, but how are you measuring the increase in power from 70-100W at a constant speed?

GhostRider62

Power? What kind of power? What duration? There are two types (at least) of muscles.

Peak maximal contraction has a range of hip angles. If you go outside those ranges, peak power declines. There are plenty of studies on that out there.

Aerobic,steady efforts is more complex and very interesting for me as a recumbent rider. O2 kinetics, hemodynamics, perfusion, etc. When Triathloners or TT racers get very low, their aerobic powers drop but with time, the numbers come up. I don't recall an Opera Singer crouching low when belting it out.

When I first got onto a recumbent, all of my power numbers were in the toilet. So, I read every research possible on the subject. It is actually pretty complex. I could point to Lemond to support the pulling and hip rocking rider or to Pantani, who did his best out of the saddle with torso almost horizontal but he also had a crit of 60

veloz

A lot of good points here (aero, knee/hip angle, push/pull) but one I didn’t see. Cyclists leaning extremely forward usually compress their abdomen which can limit lung capacity. I see this every time I fit someone with even a slight belly. As they lean forward it pushes their gut up into their lungs. You benefit from every bit of oxygen you can get and this can be limiting factor. The trick is to find the maximum payoff for each individual riders body. It’s likely that the slimmer you are and less belly fat you have, the more you’ll benefit from a lower position. Every cm counts in the wind but oxygen counts too in an extended effort. This is where drop bars with their multiple positions have an advantage. Power vs speed should be addressed here too as any stationary test likely doesn’t take air resistance into account. If you’re just riding 12-14mph recreationally, any lower position has little factor.

If you don’t think leaning forward is a factor in lung capacity just test it in your chair at your keyboard.

gregf83 

The powermeter doesn't measure power wasted by your upper body. It only measures power to the pedals. If you put more power to the pedals and don't change your position you'll go faster. If you lean forward you likely have a more aerodynamic profile and will go faster with less power. Making these type of measurements takes considerable care and attention to external factors like wind and grade.

PeteHski

Yeah I agree, that's why I was asking about power measurement. Extra Watts measured at the pedals/crank/hub will make you go faster. A more aero position will also make you go faster for the same power output. So I don't know where these 30W are coming from to maintain the same speed? Unlikely to be aero drag if you are leaning forward on the bars.

GhostRider62

I was afraid to make it......reason for lame the opera singer reference.

How one supports the torso on a recumbent can be a limiting factor, too.

I had always wondered about visceral fat pressing and making it harder for the muscles to move air in and out.

Trakhak

I just did. It isn't, at least for me. I'm skinny, though.

From one of Graham Obree's world-hour-record-winning rides:

CrankyOne

Most recent measurements have been heart rate (Garmin HRM Dual) + blood ox (Apple watch & fingertip pulseOx)+ expelled CO2 (borrowed from MN Vikings training folks).

A local company has developed a muscle lactate device that we've been playing with. Unfortunately it is muscle specific and only does one muscle at a time. When we get time we're hoping to try 4 or 6 of them to see what it can tell us.

CrankyOne

Yes. But there is a vast difference in PEAK POWER and EFFICIENCY. I don't need anywhere close to peak power when I'm riding my Opafiets to the store. I do want efficiency though.

I want to travel at maybe ±13 MPH, as comfortable as possible with as little sweat as possible and with as little effort as possible. I know both anecdotally and by statistics that given equal conditions, if I ride there sitting upright on my 40lb opafiets that I will arrive without sweat nor heavy breathing but if I ride a 20lb lean forward hybrid I'll have a greater chance of sweat and a greater chance of heavier breathing. At 13 MPH I'm producing more power at my pedal per kJ expended sitting upright than if I were leaning forward.

If I want to average 22 MPH instead of 13 MPH then I'm better off leaning forward because at these closer to peak power speeds I can produce more power / kJ leaning forward than sitting upright. HOWEVER, my efficiency is much lower than sitting upright at 13 MPH.

CrankyOne

Yes. Sort of. It will 'allow' you to go faster but not 'make' you or cause you to go faster. As gregf83 pointed out there's a difference in power at the pedal or power produced and kJ consumed in order to produce that power at the pedal.

If I'm perfectly efficient then I can produce 70w at my pedals for 0.07kJ consumed. I'm not perfectly efficient though so riding upright @ 13 MPH may require consuming 0.1kJ in order to produce 70w. Here the other 30w is going to breathing, and holding my body upright and moving my eyes around to see stuff (and maybe one leg is out of balance w/ the other, etc.).

If I lean forward though I may consume 0.15Kj in order to produce that same 70w at the pedal to propel me forward @ 13 MPH so we've an 80w difference not just 30w. That extra 50w that we consume but that is not going in to the pedals is going to my back, shoulders, arms and hands which are now expending more energy to support my body than when I was sitting upright. My neck is also using more to hold itself up from this position as are my lungs.

gringomojado

"Stand up, sit down, clap, clap, clap

burnthesheep

Endura did a tunnel study with him about several positions he used. The egg, superman, conventional UCI, and modern UCI. The egg estimated power for the hour record he achieved in that position was only about 324w. Later once that was banned, he moved to the superman 376w. In that position the estimated power was much much higher.

Again, hip angle and elbow pad width matter a lot for power production.

Just because you see a photo of a person with a narrow hip angle doesn't mean you know the full story of what's going on.

Link to video:

PeteHski

I'm asking how this "extra" power is actually being measured? Also mixing units of energy (kJ) with power (W) doesn't make any sense. Power is a rate. Energy is an amount/quantity. To state that you can produce x Watts for y kJ consumption has no meaning without a time reference.

Anyway if we are saying that 70W is going into the pedals and 30W is going into breathing, holding your body upright etc, etc. How is this 30W being measured? That's my question.

GhostRider62

I do not believe gross efficiency is impacted by position. But....don't sweat it.

satrain18

You do know that mailman was being towed with transparent fishing line.