Help!!!!!!!!!!!!! Drag factor way out!

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chrisurw
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Help!!!!!!!!!!!!! Drag factor way out!

Post by chrisurw » August 9th, 2009, 3:31 pm

Hi have searched previous links and followed instructions re checking drag readings mine are as follows 1-99 5-154 10-235 the machine itself is a model D a few years old but was unused when I got it a couple of months ago it is very clean what I need to know is how can I get the drag readings more accurate and how does the current drag settings affect my times ie 6.58 2k how far would this be out and which way
cheers

jamesg
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Post by jamesg » August 10th, 2009, 12:43 am

So long as you keep the DF between 100 and 140, there won't be much effect on your times. The best level depends on you though, the machine's impedance has to match yours.

Simplest check is to do a set of flat out 100-200m pieces at varying DFs, but with full strokes and NOT at extremely high rating, and see which is most comfortable. However first make sure your posture, swing, back, speed off the stretcher etc are all in order.
08-1940, 179cm, 83kg.

chrisurw
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Post by chrisurw » August 10th, 2009, 2:34 am

Hi I'll try this and see what it throws up
cheers hris

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johnlvs2run
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Post by johnlvs2run » August 10th, 2009, 8:28 am

If you have a model D you can remove the metal band in the middle, which on my machine resulted in a drag factor range from 100 to 360.

The reading starts over at 335/45.

Once it flips over, a reading of 70 is the same as a drag factor of 360.

I have done all of my rowing PBs through the marathon with a drag factor range of 77 to 110.
bikeerg 75 5'8" 155# - 18.5 - 51.9 - 568 - 1:52.7 - 8:03.8 - 20:13.1 - 14620 - 40:58.7 - 28855 - 1:23:48.0
rowerg 56-58 5'8.5" 143# - 1:39.6 - 3:35.6 - 7:24.0 - 18:57.4 - 22:49.9 - 7793 - 38:44.7 - 1:22:48.9 - 2:58:46.2

SirWired
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Post by SirWired » August 10th, 2009, 11:01 am

What do you mean "get the drag readings more accurate"? The drag factor itself is what the rower uses to make the final speed accurate. About the only thing you need to do is make sure the flywheel doesn't get excessively dusty, which I suppose might throw off the drag factor by some small amount, due to the slightly increased mass of the flywheel.

The drag factors you posted are well within the normal range for a Model D.

The drag affects your time based on your body composition. Speaking on extremely general terms, short and/or highly muscular and/or heavy rowers will row the best at a higher drag factor than a tall and/or very lean rower.

SirWired

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Re: Help!!!!!!!!!!!!! Drag factor way out!

Post by Bob S. » August 10th, 2009, 11:13 am

chrisurw wrote:Hi have searched previous links and followed instructions re checking drag readings mine are as follows 1-99 5-154 10-235 the machine itself is a model D a few years old but was unused when I got it a couple of months ago it is very clean what I need to know is how can I get the drag readings more accurate and how does the current drag settings affect my times ie 6.58 2k how far would this be out and which way
cheers
I wouldn't call it "way out." The range seems to be 10-20 points higher than normal, which is not all that bad.

A high drag factor range implies that there is more air flow (or denser air) than normal. That makes me wonder is there is some extra opening in the cage. Can there be a gap where it isn't bolted snugly together? Has part of the damper been removed or broken? Has part of the protective screen been removed?

Perhaps a previous owner deliberately opened the cage up a bit to get a higher drag factor range.

I suppose that there could even be a situation in which the air was dense enough to raise the range by that much. Excluding the use of the machine in a hyperbaric chamber, this would be at a very cold temperature and on a day when the atmospheric pressure was high.

I suppose that there is as possibility that the monitor is faulty. If the monitor is O.K. it should not matter much unless you want a drag factor of less than 99. Even then you could tape up part of the screen to get a lower drag factor. The important thing is that you get an accurate value from the monitor.

Bob S.

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c2jonw
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Post by c2jonw » August 11th, 2009, 2:14 pm

99-235 is a little on the high side but well withing normal range for a Model D. Drag Factor is a numerical representation of the speed of deceleration of the flywheel and so it will vary on a given machine with local conditions such as temperature, humidity and elevation (barometric pressure). Note that the monitor compensates for all of these variables so regardless of drag factor setting your work output is being accurately measured.

www.concept2.com/us/training/advanced/dragfactor.asp

C2JonW
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Concept2 employee 1980-2018! and what a long, strange trip it's been......

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johnlvs2run
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Post by johnlvs2run » August 11th, 2009, 4:41 pm

The drag factor will be higher outside or in the middle of a big room,
and lower next to a wall, especially if the fan side of the erg is right next to a wall.
bikeerg 75 5'8" 155# - 18.5 - 51.9 - 568 - 1:52.7 - 8:03.8 - 20:13.1 - 14620 - 40:58.7 - 28855 - 1:23:48.0
rowerg 56-58 5'8.5" 143# - 1:39.6 - 3:35.6 - 7:24.0 - 18:57.4 - 22:49.9 - 7793 - 38:44.7 - 1:22:48.9 - 2:58:46.2

hhoppert
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Drag way out...

Post by hhoppert » August 12th, 2009, 3:00 pm

So I recently started rowing, and there are three machines at my local gym. WHen I measured the drag factor on them, they are all around 180-290 (180 with the damper closed, 290 with it open).

Each machine is a little different, but that's the general range. These are old machines. Is there something wrong with them?

SirWired
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Post by SirWired » August 12th, 2009, 4:33 pm

What model are those? If they are C/D/E, are they missing the metal grille that runs the circumference of the flywheel cage? If model B, are they running on the large or small sprocket?

SirWired

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Post by pjc » August 12th, 2009, 7:44 pm

c2jonw wrote:Drag Factor is a numerical representation of the speed of deceleration of the flywheel and so it will vary on a given machine with local conditions such as temperature, humidity and elevation (barometric pressure). Note that the monitor compensates for all of these variables so regardless of drag factor setting your work output is being accurately measured.

C2JonW
Ahhh, thanks Jon!

I have been wracking my brain trying to figure out the "magic" of the monitor. It seems the workouts are always accurately measured, even when the airflow is somehow obstructed in some weird way, or when the air is more/less dense, etc. The resistance might change in such a case, but the measurement remains accurate. How could such a thing be, I wondered...

You just measure the deceleration of the flywheel upon each recovery! This will always give an accurate measurement of the resistance being faced by the flywheel. Brilliant!

Thanks for explaining.

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Post by hhoppert » August 13th, 2009, 5:01 pm

SirWired wrote:What model are those? If they are C/D/E, are they missing the metal grille that runs the circumference of the flywheel cage? If model B, are they running on the large or small sprocket?

SirWired
These are model Bs running on the large sprocket. Thanks for the help!

SirWired
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Post by SirWired » August 13th, 2009, 10:32 pm

Gee even for a B, those drag factors seem high, especially on the large sprocket. Maybe the axle bearings are going? I dunno... Time to give C2 a call.

SirWired

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Post by Bob S. » August 13th, 2009, 11:38 pm

SirWired wrote:Gee even for a B, those drag factors seem high, especially on the large sprocket. Maybe the axle bearings are going? I dunno... Time to give C2 a call.

SirWired
My old B used to get over 150 with the damper closed and that was at 4000 feet of elevation where the drag factors run lower because the air is less dense. I don't remember checking to see what the max would be. I also used the large sprocket, which makes for a lighter feel, but should not affect the drag factor reading on the monitor, since that is measuring only the deceleration of the flywheel, not the effort that it takes to accelerate it.

The drag factor of a B can be brought down by using a lot of different methods of adding shielding to the wire frame, but if they are in a gym, the management might object to it.

On my own B, I experimented with a cardboard box that fit quite neatly over most of the wire cage. It brought the DF all the way down to 50. I didn't ever work out with it like that, but just used it with the closed damper and the usual 155 DF, since I was used to that, having used the B for about 10 years before I replaced the old PM(1) with a PM3 and learned about drag factor for the first time. A few months later I got a model D and learned to get used to a much lower DF, 115-125.

Bob S.

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johnlvs2run
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Post by johnlvs2run » August 14th, 2009, 2:24 am

hhoppert wrote:These are model Bs running on the large sprocket. Thanks for the help!
http://www.c2forum.com/viewtopic.php?p= ... ube#106286
bikeerg 75 5'8" 155# - 18.5 - 51.9 - 568 - 1:52.7 - 8:03.8 - 20:13.1 - 14620 - 40:58.7 - 28855 - 1:23:48.0
rowerg 56-58 5'8.5" 143# - 1:39.6 - 3:35.6 - 7:24.0 - 18:57.4 - 22:49.9 - 7793 - 38:44.7 - 1:22:48.9 - 2:58:46.2

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