Drag Factor

[King]

I recently updated my model B with a PM3. While checking my drag factor, at the easiest setting, I noticed that 180 is the lowest setting that I can achieve (it has always pulled harder than the newer gym models). When I use my local gym's model C or D I usually set the flywheel at a 4 setting, resulting in a drag factor of approx 116 to 120. I would like to be able to set my model B at that lower range. Do all of the older model B's have a higher drag factor, or is there something I can do to lower it, replace some parts?
Thanks

[c2jonw]

King,
This should be a help: http://www.concept2.com/us/support/manu ... arison.pdf
The key here is that while the drag factor range of a model B is much higher than later machines, the large 15 tooth sprocket on the B will give you a lighter feel than the 14 tooth sprocket used on the C,D & E with the same drag factor. The "Speed Ring" that is mentioned on the chart is basically an air inlet block that reduces the drag factor range of a model B. It was an accessory that many rowing coaches wanted at the time, and we still carry it- part #372 and the cost is about $12. Alternatively you could use some stratigically placed duct tape. C2JonW

[King]

C2JonW,

Thank you for all of the information. I am ordering a Speed Ring, and will give it a try. King

[jag]

Thanks for your willingness to support the older model PMs.

I've noticed the same thing with my Model B and PM2 - namely the smallest drag factor I can get is about 175 (vent fully closed). Also the drag factor the PM2 measures is the same for either small or large sprocket - although the comparison table link indicates the relative drag factor should be quite different depending on which sprocket is chosen.

I'm also confused by this statement: "the large 15 tooth sprocket on the B will give you a lighter feel than the 14 tooth sprocket used on the C,D & E with the same drag factor". So is this saying that a drag factor of 175 on the Model B is not comparable to a drag factor of 175 on the Model C/D/E? In which case drag factor isn't the best way to set up a Model B - that it should be done based on feel and not on the drag factor? Which is maybe what the comparison table is doing?

I found the Speed Ring (aka Wind Damper Ring part #372) in the parts list, but there is no picture of it or installation instructions for it. How much disassembly is required to install it? Is there a picture of it somewhere online?

[JRBJR]

My Model B has the speed ring installed, dampers completely closed, and the chain on the sprocket closest to the flywheel. And my PM2 shows a drag factor of 125.

Installing the speed ring requires that you remove the caged flywheel assembly from the two black mounting arms. First disconnect the wire from the PM2, then remove the two screw that secure the flywheel to the arms and put the flywheel on a smooth flat surface (recommend a large towel for cushioning) with the damper side up. Install the speed ring with screws provided to the plastic mounting points all around the damper. Then reinstall the flywheel onto the mounting arms, reconnect your PM3 wire, and you're ready to go. You should notice a significantly lighter feel to the B.

[Cyclist2]

There is a conversion chart for damper settings and "feel" between the various machines, here it is:
http://www.concept2.com/us/support/manu ... arison.pdf. It's on the C2 site if this doesn't work, search under "damper comparison". I have a model B and and model C. I installed a home made speed ring on the B to reduce the DF, but since the gearing is different, when the two ergs feel about the same they don't have the same DF (B: 150, C: 130). The speed ring I made is just some masonite fiber board cut like a donut and zip tied to the cage.

[Carl Watts]

Made a "Speed Ring" for my Model C out of a bit or corrugated cardboard a long time ago!

Now with the damper on 10 and the ring installed, which is just a press fit donut, the hole is symmetrical for the air to enter the fan housing. Had to play with the ID a little to get the DF at 136 but it works fine.