Dynamic vs Stationary

[Ultramega OK]

Unfortunately there are issues with all of the dynamics the way I see it. C2 is a great company and their customer service is second to none but like Johnlvs2run I just wasn't liking what I saw on the video footage and also from folks who had tried it. It kind of seemed like they were forced into a certain design because of patent constraints or something. That last bit is pure conjecture on my part. Rowperfect sounds like an awesome maching but I wasn't going to drop 3k + on something that I couldn't lay my hands on to try out. The Oartec on the other hand was comparable to the C2 in price and many on the forums spoke highly of it. I went with that option. Overall I like it but I would change a few things and I have changed a few as well. I changed the seat and the handle to the concept 2 variants. The seat was way too soft, after about 10k I was getting sacral chaffing. I prefer also the slightly curved C2 handle. The other thing is the monitor. It does not allow the storage of data like the C2 PM does. It is pretty easy to use and gives info about stroke length and drive ratio that the PM doesn't but it has its limitations. For example it can only display one of the following at any one time: HR, SL, Drive ratio, DF, avg spm If you want to see another metric you have to hit the tech button. Also if you like rowpro you are outta luck. On the plus side, their customer service is responsive and they tell me they will have a computer software program coming out in the fall. Overall I am happy with the purchase but I think it would be the ultimate erg if it could have a C2 PM4 on it.

[johnlvs2run]

It kind of seemed like they were forced into a certain design because of patent constraints or something.

Regarding RP's patent, if they have one, I have long wondered why that has been any obstacle. 1xsculler's DIY with a C2 machine and parts is not like a RP at all except it faces the same direction, and I doubt that it infringes on any patent. If so then simply change that part of it to something different and better. There are many ways to make a housing slide on a rail that came along long before RP was here and I'm sure that C2 (or someone from the forum) could come up with an improvised design that is better. I do like 1xsculler's DIY very much and feel it has great potential. Were C2 to redesign the front, make it lighter and produce the machine with a 2" railing then I might be interested. Also improve the drive to minimize any delay at the catch. I wonder why C2 went with a cord instead of a belt, unless it was easy to attach to chain.

Rowperfect sounds like an awesome machine but I wasn't going to drop 3k + on something that I couldn't lay my hands on to try out.

Same here. I'd also be more comfortable if C2's dynamic and the Oartec Slider were quite a bit less.

The Oartec ... monitor. It does not allow the storage of data like the C2 PM does. It is pretty easy to use and gives info about stroke length and drive ratio that the PM doesn't but it has its limitations. For example it can only display one of the following at any one time: HR, SL, Drive ratio, DF, avg spm If you want to see another metric you have to hit the tech button.

I still say you can hook up a pm3 to the slider and get all the usual pm3 information. It might not match up exactly with C2 times but, again, I see that as being a good thing.

On the plus side, their customer service is responsive and they tell me they will have a computer software program coming out in the fall.

Will that be an upgrade to the monitor or a computer program? Oartec told me they were planning a ranking system but so far I've not seen one. If I could see that people were actually using the machine and ranking their times, then this would make it much easier to get one. Right now it's kind of like the phantom erg that is out there somewhere but no one knows where.

Overall I am happy with the purchase but I think it would be the ultimate erg if it could have a C2 PM4 on it.

Well then hook one up.

[Ultramega OK]

As far as hooking a C2 PM up to the Oartec... it isn't that easy. It would require disassembling the Oartec drilling some holes and mounting the monitor pickup from a model C static. I have no schematic of the Oartec innards and for that reason I fear that should I take it apart I will not be able to correctly reassemble it.

[Rockin Roland]

As far as hooking a C2 PM up to the Oartec... it isn't that easy. It would require disassembling the Oartec drilling some holes and mounting the monitor pickup from a model C static. I have no schematic of the Oartec innards and for that reason I fear that should I take it apart I will not be able to correctly reassemble it.

It can be done and has been done. I've mentioned it here before on this forum. A few years ago I had a demo on an Oartec Slider which was their original prototype model. It had two sensor cables on it. One for the Oartec monitor and the other for a C2 PM(using a C2 sensor cable). I quized the designer/owner of Oartec about this. He said that they ran both monitors to test the calibration of the Slider so that it matched a C2 erg. He said that it wasn't all that difficult to fit the C2 sensor cable.

The bofins at C2 may not like it but it can be done. Oartec will even fit it for you if you push them hard enough(although it's not their intention to market their ergs like that) because they were going to do it for me until I decided to purchase the Rowperfect indoor sculler instead.

I have compared my own workouts between a static model D, model D on slides and an Oartec Slider to find virtually no difference between my results(though my technique is pretty good so no adaptation was required). Even my Rowperfect results were pretty close if I used the 95kg 4- setting.

Obviously C2 are going argue against this so that they keep their market share intact.There are differences in pulley designs. However I've seen enough evidence to believe that you can hook up a PM4 with Rowpro to an Oartec Slider and get the same performance results. Sure, someone might one day do a very comprehensive scientific test and find a slight variance. Who cares! Unless your trying to log a WR result it shouldn't matter to the majority of erg users as most wouldn't be able to detect any difference.

[Carl Watts]

The design of the fan would need to be identical on the Rowperfect, even then your results on the PM3/PM4 wouldn't count in the Rankings as it's not a C2 Erg. Great for getting on RowPro though for training purposes, the more the merrier, just don't go comparing your results to others using a C2.

[Rockin Roland]

Great for getting on RowPro though for training purposes, the more the merrier, just don't go comparing your results to others using a C2.

Who would know ???
If you managed to hook up an Oartec Slider to Rowpro and raced others on C2s on line, why would it matter?
I once seriously considered doing that myself. If Oartec claim the calibration is the same then all competitors, regardless of the type of erg, have to do the same effort of work to cross the line together.

[Carl Watts]

You would know so I guess you don't have a conscience.

I have the knowledge to modify a Model C to enable me to row at 1:30 pace for the 10K (that's even faster than Ranger)using a PM2+ with RowPro but I wouldn't. Well no point really until we get a webcam system as part of RowPro and I can see the look on peoples faces !

I'm very thankful that Concept 2 came up with the IND_V system, the rankings system would be pretty worthless without it.

[johnlvs2run]

Carl, you weigh 220 pounds, and you put your times in the rankings. Having a conscience doesn't have anything to do with it.

I rowed a 6:40 2k a couple years ago with a modelD pm3, with the IND-V, no one knows how I did it and I can do it any time. Does that make the rankings worthless now.

The Slider and C2 times are apparently very close. But there is no accounting for weight. On the water everyone has to pull their own weight.

[NavigationHazard]

(snip)
The Slider and C2 times are apparently very close. But there is no accounting for weight. On the water everyone has to pull their own weight.

No they don't. There are per-rower differences inherent in the FISA-mandated minimum weights for boats of different classes.

FISA minimum weight for a 1x is 14 kg. Thus a 70kg male LW single sculler in a weight-limit shell will have to move 84kg of boat+rower. FISA minimum for a 4- is 50 kg. 70kg rowers in a minimum-weight coxless four will have to account for 70 + (50/4) kgs of mass or 82.5 kgs per rower.

Rowers in events with coxes have to move not only themselves and their boats but also their coxes. FISA minimum weight for an 8+ is 112 kg for the boat; men's coxes must weigh at least 55 kg. Thus 70kg male lw rowers in a weight-limit viii with a weight-limit cox will have to account for 70 + (112/8) + (55/8) kgs of mass or 90.875 kgs per rower. Carrying weight is proportionally greatest in the coxed pair. FISA minimum weight for that is 32 kgs. Thus 70kg male rowers in a minimum-weight 2+ with a minimum-weight cox must account for 70 + (32/2) + (55/2) kgs of mass or 113.5 kgs per rower. There's a reason that the coxed pair is called the lead sled.

[johnlvs2run]

FISA minimum weight for a 1x is 14 kg.  Thus a 70kg male LW single sculler in a weight-limit shell will have to move 84kg of boat+rower. 

70kg rowers in a minimum-weight coxless four will have to account for 70 + (50/4) kgs of mass or 82.5 kgs per rower.

Those are interesting figures.  For a given average weight of the rowers in a certain class, the average displacement of the water is greatest in the 1x.  The average displacement of an 8x is less than a 1x, and the shape of the boat is contiguous, having 1X 8x, rather than 8X 1x, so the average resistance is less and this accounts for the difference in times.  In either case, however, the rowers have to pull their own weight (resistance), so there is no free lunch.

[NavigationHazard]

Who said anything about a free lunch? As a general principle, more mass OTW = more displacement = more wetted surface area and thus more drag. In the real world the effects vary from boat to boat depending on the number of rowers and on whether there's a cox or not. Design also comes into play a bit, as an viii hull (say) won't be quite the same as a scaled-up 1x. Thus it's true that as a general principle, there's a tradeoff between the added power that can come with greater mass (power which scales allometrically) and the added drag that comes with it. But it's fatuous to argue from this that water somehow magically equalizes LWs and HWs.

Also as a general principle, more mass on a static erg = more energy cost just moving it back and forth every stroke. There's less of a 'penalty' for the added power that can come with added mass than there is OTW but it exists nonetheless. If you think weight on an erg is an advantage per se, go to the store and buy a couple of 25 kg weights and sit on them while you try to row. Guess what. It'll be considerably harder than it would be without them.

[NavigationHazard]

Or to sum up my last post, no rowers do NOT "pull their own weight." They have to move their own weight plus their share of their boat's weight plus their share of a coxswain's weight if the boat has one. Oddly enough, on a static erg rowers actually do have to shift precisely their own weight.

[Bob S.]

Or to sum up my last post, no rowers do NOT "pull their own weight." They have to move their own weight plus their share of their boat's weight plus their share of a coxswain's weight if the boat has one. Oddly enough, on a static erg rowers actually do have to shift precisely their own weight.

Please excuse a little nit-picking. I just can't resist being a bit pedantic here. The seat is moving as well, but, more importantly, various parts of of the body are moving different distances. On a static the feet don't move at all, except for a little wiggling. On a dynamic the feet move a lot and the body doesn't move nearly as much. For some rowers the head movement is another item entirely. Then there is the Danish <6' lwt who makes a supposedly static erg jump so much that someone has to lend a foot to hold it in place.

I agree with you in principles, but would avoid the precisely.

Bob S.

[hjs]

Or to sum up my last post, no rowers do NOT "pull their own weight." They have to move their own weight plus their share of their boat's weight plus their share of a coxswain's weight if the boat has one. Oddly enough, on a static erg rowers actually do have to shift precisely their own weight.

Please excuse a little nit-picking. I just can't resist being a bit pedantic here. The seat is moving as well, but, more importantly, various parts of of the body are moving different distances. On a static the feet don't move at all, except for a little wiggling. On a dynamic the feet move a lot and the body doesn't move nearly as much. For some rowers the head movement is another item entirely. Then there is the Danish <6' lwt who makes a supposedly static erg jump so much that someone has to lend a foot to hold it in place.

I agree with you in principles, but would avoid the precisely.

Bob S.

at most races the ergs are taped to the floor to prevent moving, if not almost all not to slow ergers would be "floating" around on the floor

[Bob S.]

Then there is the Danish <6' lwt who makes a supposedly static erg jump so much that someone has to lend a foot to hold it in place.

Bob S.

at most races the ergs are taped to the floor to prevent moving, if not almost all not to slow ergers would be "floating" around on the floor

That may be the usual case, but one video of Stephanson clearly shows someone using his foot to hold the erg in place.

Bob S.