Rower is too hard to row

[Sakly]

This explanation is nice, but I think it does not contribute much to the mentioned problem.
A strong bungee cord will ensure that the chain retracts fast enough without adding anything that can be felt by a user in a 2k TT or below distances, as the recovery is typically so fast, that the chain wobbles anyway. The wobble gets smoother, if the bungee has more tension. This could lead to a better catch as the chain is already straight.
Only in steady states/low rate training this could play a role, but it's completely out of interest for these pieces.

[Nomath]

This explanation is nice, but I think it does not contribute much to the mentioned problem.
....

The topic poster is asking about his 7:45 for 2K, not your 6:45 or the 17.6 sec for 100m in the Youtube video. The chain will retract perfectly at his pace and he will feel the bungee tension. Just let the handle go in the finish position and you can see and hear how fast it retracts.

Let’s please stick to the TP case !

[Sakly]

This explanation is nice, but I think it does not contribute much to the mentioned problem.
....

The topic poster is asking about his 7:45 for 2K, not your 6:45 or the 17.6 sec for 100m in the Youtube video. The chain will retract perfectly at his pace and he will feel the bungee tension. Just let the handle go in the finish position and you can see and hear how fast it retracts.

Let’s please stick to the TP case !

It's not about the pace, it's about the speed of the recovery = rate. If you go all out at a rate of 30 (or faster) for a 2k, but use strokes with low effort, you will get a 7:45, but also fast(ish) recovery movements.
Anyway, without proper measurements of all the potential influences, noone will ever know the specific root cause of this feeling.

[JaapvanE]

It's not about the pace, it's about the speed of the recovery = rate. If you go all out at a rate of 30 (or faster) for a 2k, but use strokes with low effort, you will get a 7:45, but also fast(ish) recovery movements.

It is all about recovery time, not even rate. Most gymgoers struggle with the drive and have a too fast recovery,resulting in the same chain behaviour. Rowing effectively is quite counter-intuitive at that point.

Anyway, without proper measurements of all the potential influences, noone will ever know the specific root cause of this feeling.

Agreed. It could be a "death of a thousand cuts" situation where all small things being a little looser can result in a different feeling.

And it can be that the rythem is slightly different which can have a huge perceptional effect. I experienced that when transitioning from DF90 to DF100. At DF90 I was extremely happy (I thought), machine felt light as a feather and I was setting PR's. Just on Stava desktop I had my pace move up and down like a sinoid, probably a rounding thing I thought. At DF100 I felt like I hit a brick wall, the machine felt heavy like a truck at my usual 10K, and I struggled to finish a HM. After three weeks at DF100 I had to step back due to overtraining my elbow joints. Physically, clearly something was happening.

When I started to look at the data much more carefullly, I noticed the at DF90, about 1 in 5 catches was perfect, and the rest was a bit too late. The unrounded Strava desktop data was actually right: my speed was actually fluctuating stroke by stroke. The smoothened and rounded data from the PM5 was masking that. One strong stroke, followed by 4 weaker strokes until the flywheel was slow enought to catch perfectly again. At DF100, the strokes were not really heavier per se, but that ratio changed to 4 out of 5 stronger strokes. That quadrupled the number of strong strokes in a session overnight. No wonder my elbiws were protesting.

Moral of my story is that rowing is quite a delicate movement and aside a million small changes in the machine, it can also be the human itself or the interaction between the two.

[Dangerscouse]

And it can be that the rythem is slightly different which can have a huge perceptional effect. I experienced that when transitioning from DF90 to DF100. At DF90 I was extremely happy (I thought), machine felt light as a feather and I was setting PR's. Just on Stava desktop I had my pace move up and down like a sinoid, probably a rounding thing I thought. At DF100 I felt like I hit a brick wall, the machine felt heavy like a truck at my usual 10K, and I struggled to finish a HM. After three weeks at DF100 I had to step back due to overtraining my elbow joints. Physically, clearly something was happening.

When I started to look at the data much more carefullly, I noticed the at DF90, about 1 in 5 catches was perfect, and the rest was a bit too late. The unrounded Strava desktop data was actually right: my speed was actually fluctuating stroke by stroke. The smoothened and rounded data from the PM5 was masking that. One strong stroke, followed by 4 weaker strokes until the flywheel was slow enought to catch perfectly again. At DF100, the strokes were not really heavier per se, but that ratio changed to 4 out of 5 stronger strokes. That quadrupled the number of strong strokes in a session overnight. No wonder my elbiws were protesting.

Moral of my story is that rowing is quite a delicate movement and aside a million small changes in the machine, it can also be the human itself or the interaction between the two.

This is interesting and notable, albeit quite a subtle issue that will almost certainly go unnoticed. I've never thought of it that way.

I experimented with df 114, instead of circa 123 for this morning's session, and it definitely felt different. Not as much as yesterday's df113, which was my first session with a lowered df, but there's a notable difference and I'm sure that it will feel even more notable if I increased to 133

[Slidewinder]

I'm astounded that with all these arguments floating around the internet on drag factors, bungee cord tension and other obscure factors on rowing efficiency and speed that noone has made a chain yanker machine to put all these arguments to rest. Where's Jamie and Adam from Mythbusters?

Researchers at the University of Ulm, Germany have built a 'chain yanker' machine. They have done some tests and have published a couple of papers. They plan to do more, and hopefully, will put many of these arguments to rest.

Speaking of the Ulm test rig, the researchers recently published a paper related to the topic of this thread. Titled: "Determination of Mechanical Work and Power During the Recovery Phase of Ergometer Rowing" (Medicine and Science in Sports and Exercise - Sept. 2022). I can only find the abstract. Unfortunately, their measurements of power output during recovery make no reference to the strength of the elastic cord.

When I learned of the Ulm Test Rig I wrote to the team with research suggestions and received warm thanks for my interest in their work. They agreed that the effect of variations in elastic cord strength should be investigated. That was before publication of the current paper, so I am disappointed that the effect of variations in elastic cord strength on power output during the recovery was not part of the study. I'm starting to wonder about those guys. Have C2 operatives infiltrated Ulm university and 'got to' them... They could have answered this question. They still could answer it. It took thirty years (from the time of the Model for someone to finally design and build a test rig for rowing ergometers. It is an important development, because it removes the human variability factor from test results. But the Ulm team is moving at a glacial pace. I have actually thought of building my own test rig (their first paper details its construction), because at the rate the Ulm team is going it will be another thirty years before this and other questions are answered.

[OhBeWan]

OP, here. Thanks for all of the interesting information on F=MA, S=1/2 AT^2, V=AT and Torque=Force times moment arm. No one mentioned A=9.8M/S^2. I am just some old slow guy who was trying to figure out why my home rower was so hard to pull. At some point folks were comparing my examples of 7:45 and 7:50. The 7:45 on the in town rowers was AFTER a workout. The 7:50 on the home rower was at the BEGINNING of a workout. I used the term "fresh" and someone thought that meant I had not warmed up and that was the cause of my home rower problem. My definition of "fresh" means fully warmed up and ready to go.

Someone suggested I remove and examine the heavily metal disc called a flywheel. I did. It appears to be in great shape with lots of grease. A cursory review of the ball bearings supporting the flywheel shows them in good shape. I sprayed some silicone which is probably wrong, but it didn't help or hurt. Please note that this is the first time I have done this so it couldn't be the reason for the problem.

A suggestion was made to remove the flywheel and see if the handle moves freely. Yessirree. There is nothing holding it down.

A suggestion was made that it was possible that my 3.3 million meter rower was still in the break-in phase of its useful life. Actually, they did not suggest that. I believe they were just saying that on some machines increased friction is possible over some period of use.

Acquiring some scale to test my home rower and the ones in town is behind my motivation. I was kind of hoping I could replace some $20 part so as to get my rower to be comparable to the ones in town.

Oh, one more bit of information. I have a brand new SkiErg at my house. The times on it are equal to the machines in town. So, the problem is not the elevation nor my maintenance. Of course, since the stroke on a SkiErg is down, gravity is a consideration, but since PV=NRT I shouldn't have any problems (I am just joking here, folks).

Thanks again for the suggestions - many of which I tried.

[jackarabit]

Rut roh. That one hurt!

[jamesg]

At some point folks were comparing my examples of 7:45 and 7:50.

The 2k is a difficult distance to say the least; and 5s is not a large difference. If you have the details of pacing and ratings, there may be a clue.

One suggestion of how to do a 2k when racing was called the French Protocol. Pacing was based on a 500 test, doing the 2k at 92, 88, 88 and 91% of the 500 test pace in the four splits.

[jamesg]

Today's WOD is 8x500m 2'R, another test for 2k racing, and no fun at all.

If you have doubts, do all your tests on the same machine. They all serve to get us fit, whatever the numbers.

[Ombrax]

The 7:45 on the in town rowers was AFTER a workout. The 7:50 on the home rower was at the BEGINNING of a workout.

If you're really motivated to investigate further you could do a few test cases where you row both machines under the same conditions, e.g. both at the start of your routine. Beyond that, you could do some DF investigations and bungee-wise maybe get a fish scale and compare bungee force that the start, middle and end of a handle pull. A luggage scale is probably overkill, since that will likely be less accurate - for that full scale (geek joke) will be over 100 lbs.

I happen to have one of these (see link below) and it works well. (I did not get it to measure C2 erg bungee forces. ; )

https://awscales.com/aws-44-x-0-1lb-yel ... ing-scale/

Good Luck

[jackarabit]

After 5 pages of geeksquint, my vote goes to mechanical break in or “run In” as the advantage of the gym rower over the “new” home machine, assuming (well-maintained) gym machine’s hours of operation significantly exceed home rower’s.

Stu mentions a cheerleader effect on performance of having an audience—not really a quant thing, more psychosocial imperative. You might try inviting one or more gymrats to your home to observe your test run, see what pops up.