Damper setting - I don't get it

[outsidenote]

Wouldn't a better comparison with damper setting be comparing a large oar blade with a smaller one? With a large oar blade you grab more water so the boat goes further for the same pull, but to pull at the same rate takes more power. If you can't provide that power your pull rate drops negating the benefit of a large oar. I think that comparing a sleek and heavy boat makes it seem like you work harder if you push the damper up, but thats not the whole truth.

[hjs]

Wouldn't a better comparison with damper setting be comparing a large oar blade with a smaller one? With a large oar blade you grab more water so the boat goes further for the same pull, but to pull at the same rate takes more power. If you can't provide that power your pull rate drops negating the benefit of a large oar. I think that comparing a sleek and heavy boat makes it seem like you work harder if you push the damper up, but thats not the whole truth.

Not really, a bigger oar would move with the same speed through the water. Using a higher drag will slow down the strokespeed. Thats a difference.

Strokerate in itself says nothing. A stroke has a powerfase plus a recoverfase. If you would stroke slower and make the recoveryfase with the same amount of time faster, the rate would be the same, but the speed would be lower.

[Bob S.]

It is all about drag, air on the erg and water on the boat. Instead of the heavy boat/light boat, think of the trick that is often done to create a higher drag in a boat. Strap a bungee around a sleek, light-weight racing shell and you suddenly have a vessel that has a lot more water drag with only a few ounces of added weight. I have never tried it but, apparently, a number of OTW rowers use this in training to improve the power of their stroke. This is not a true analogy in this case, since the boat with the extra drag will go slower with the same amount of effort. On the erg, the calculated pace is adjusted to account for an increase in the drag, so equal effort produces equal results.

Bob S.

[JLB123]

Drag = bike gears

[hjs]

Drag = bike gears

Nope, you don,t get it

[JLB123]

Drag = bike gears

Nope, you don,t get it

OK, as thought experiment, imagine C2, instead of using a flywheel, decided to stick with the original chain and gears approach. And setting drag higher now means selecting higher gear.

Assuming I'm just paddling along at constant speed, what is different versus the flywheel? What would difference between changing gear and changing drag to flywheel be?

[hjs]

Drag = bike gears

Nope, you don,t get it

OK, as thought experiment, imagine C2, instead of using a flywheel, decided to stick with the original chain and gears approach. And setting drag higher now means selecting higher gear.

Assuming I'm just paddling along at constant speed, what is different versus the flywheel? What would difference between changing gear and changing drag to flywheel be?

If you put it that way yo are right, but thats not how it is.

On a bike you paddle with a constant pace, there is no rest/recovery fase. If you keep the spm the same and shift to a higher gear you go faster.
Not so on the erg, if you use a constant spm, you have a drive fase and a recovery fase, only the drivefase gives energy to the wheel. You have different rowers using the same drag and spm but still go at a very different speed, they have different drivetimes in the first place, and in the second also the drivelenght is not fixed like on a bike, build of the rower and range of backswing matters also.

Only when you would use a very constant range of motion and keep both spm and drive time constant a higher drag will give a higher speed. So a big difference with a bike where can,t change the range of motion and don,t have a limited paddletime.

[jamesg]

Drag serves to slow the flywheel between strokes, nothing else. To see why this is needed, just drape a towel over the cage and pull a few strokes.

We adjust drag so that the flywheel speed at the catch lets us pull a long stroke quickly but with plenty of force. We set the drag to let us work at our own ideal combination of force, length and speed. This combination lets us maximize Work done: Work = Length x Force. Work shifts boats and is said to get us fit. If you want to get fit, do plenty of work, i.e. keep going. Low drag, but not too low, will let you move fast and reasonably hard. Low rating will let you keep going even if unfit. As you get fitter, increase the rating to produce more Power. When you can pull 200W at 20 you're nearly there, or at least know how to get there.

What would difference between changing gear and changing drag to flywheel be?

Bikes and ergs are different. On a bike we adjust gearing to suit the terrain, but can't adjust the drag. On the erg there's only one gear but we can adjust drag. In both cases we are adjusting the force/speed combination to suit ourselves and the characteristics of our muscles.

[JLB123]

OK, as thought experiment, imagine C2, instead of using a flywheel, decided to stick with the original chain and gears approach. And setting drag higher now means selecting higher gear.

Assuming I'm just paddling along at constant speed, what is different versus the flywheel? What would difference between changing gear and changing drag to flywheel be?

If you put it that way yo are right, but thats not how it is.

On a bike you paddle with a constant pace, there is no rest/recovery fase. If you keep the spm the same and shift to a higher gear you go faster.
Not so on the erg, if you use a constant spm, you have a drive fase and a recovery fase, only the drivefase gives energy to the wheel. You have different rowers using the same drag and spm but still go at a very different speed, they have different drivetimes in the first place, and in the second also the drivelenght is not fixed like on a bike, build of the rower and range of backswing matters also.

Only when you would use a very constant range of motion and keep both spm and drive time constant a higher drag will give a higher speed. So a big difference with a bike where can,t change the range of motion and don,t have a limited paddletime.[/quote]

Agree with all that. My argument is that, for a given, semi-experienced rower, and excluding the start & finish of a piece, stroke length and ratio are (or at least should be) constant. Implication of keeping these constant is that as drag goes up, so does work per stroke (much as it does on a bike)

Obviously agree it's not the case that all rowers rowing at the same rate and drag pull the same split

[Bob S.]

The ratio should not be constant. There should not be much variation in the drive time - roughly 0.7 seconds, but the recovery time varies over a wide range, depending on the rate. It can be almost as short as the drive time, i.e. a ratio of 1/1, or as much as 6 times as long, a recovery/drive ratio of 6/1

Bob S.

[hjs]

Agree with all that. My argument is that, for a given, semi-experienced rower, and excluding the start & finish of a piece, stroke length and ratio are (or at least should be) constant. Implication of keeping these constant is that as drag goes up, so does work per stroke (much as it does on a bike)

Obviously agree it's not the case that all rowers rowing at the same rate and drag pull the same split

True, but that means you could only vary the drag a little, 10% more drag would 10% more Energy needed, if you increese the drag more you can,t keep the same stroke patern.

On a bike, if you keep the some alike, everything else stays the same. On the erg you have to do that yourself.

[Carl Watts]

The Erg can be very loosely compared to a bike however or the gears on a bike can be used as an analogy of how the Erg works, there is still and optimum Drag setting on the Erg for each individual depending on their rating and pace in the same way there is an optimum gear on a bike for a given terrain and speed.

The optimum Drag as you will find is very hard to find however and most people just get away with setting it over a small range that you find with experience and plus or minus a bit for the numbers showing on the monitor makes little difference.

Think of it this way you have about 200 gears on the Erg and perhaps 18 on a bike and a bike has to cover a vastly different terrain. The Erg has a constantly adjustable setup that is "Analogue" but a bike has fixed gears like a "Digital" system.

Cars have moved to the CVT system that no longer has gears but its a constantly variable system to optimise the engines torque/power to maximise fuel efficiency. The Erg is like a CVT system and obviously if you have the best drag setting that suits you then you will achieve your best possible time.

Pretty much a setting on the Erg of between 110-130 suits most people with a higher drag than this for short sprints, in exactly the same way you would use a different gear on a bike for a short sprint. You can only rate up so far with x amount of leg speed the same as you can only pedal so fast, sooner or later you need to change gears.

[jackarabit]

Too much talk about analogous mechanism where there ain't any. OTW rowers are quickest to recognize that erging is a simulation of sweeping/sculling. Think a minute here. Who developed the ergometer we use? In a reasonably narrow boat with fine entry and run (forget the extremes of barge and splinter), the most efficient application of effort by oar propulsion maximizes the forward momentum of the boat after the finish (oar rolled out of the puddle). The boat always slows at the catch when the blade is squared and immersed but the slowing is minimized by a stroke rate and stroke speed which synchs oar shaft and blade speed to apparent water speed relative to the boat and occupant(s). This ideal relationship of blade speed to water speed is simulated on the erg by a stroke rate and stroke speed which allows the fan/flywheel to slow (decay of forward momentum or run of the boat is precisely analogous) to a speed which the leg extension of the erger can easily and repeatedly synch to or "catch."

High drag slows the boat/erg mech very quickly. Low drag slows the boat/erg mech more slowly. It's really that simple and surely everything should be made as simple as possible and no simpler (or more complicated). Even Speedy recognized that the water rushing by had some bearing. Fare ye well, Speedy! Jack

[Carl Watts]

A bike is a good example because far more people have ridden a bike or driven a car compared to those who have rowed on the water.

OTW is totally meaningless to the majority of Erg users.

[Rowing_DJ]

Here's a question that perhaps someone could answer (sorry if it has already been covered, and/or is a really idiotic question!)...

If two rowers are exerting the same force and SPM but one has his damper set to 3 and the other set to 7, which one is going faster/further? In my head it would be the guy on setting 7, but I'm not sure if that's correct?!

Thanks!