BikeErg watts at low cadence

[argaudette]

Hi, I am considering purchasing a BikeErg to compliment my Model D rower and an upgrade to my indoor bike, but I am wondering about the wattages that can be produced at lower cadences, 60 rpm for example.

I am coming from a staionary indoor bike with a weighted flywheel and friction resistance, so I am used to having the ability to crank down the resistance to the point where it hurts at any cadence. I do not have a power meter on my bike but my guess is I can produce somewhere in the 300 watt range, or more, it's really up to what you can push as you can crank the felt pad down until the wheel stops. It is great for low cadence training, which is useful for training for hill climbs in the real world.

I found a chart for WattBike, which gives approximate power numbers at specific cadences and damper settings, of course each unit would vary some.
https://support.wattbike.com/hc/en-gb/a ... nce-Tables

I am not sure which version the BikeErg would be more comparable to, but for the "Trainer" version, the WattBike only has 70W resistance at 60 rpm and damper setting of 10, the "Pro" is a bit more at 125W, but still not that much. It would be great if Concept2 had a chart like this for the BikeErg.

If someone with a BikeErg could post a few power numbers at specific cadences and damper settings that would be very helpful in my purchase decision. Thanks!

[Slothful1]

I couldn't decide what I should do for training tonight, so thanks for the idea! This is what I put together - watts might have varied a bit around each number but I tried to get the cadence and power to settle on a representative figure before I recorded it. I did the minimum and maximum drag factors and then a series in the middle.

Dave

Code: Select all

DF	Cadence		Watts
46	60		47
46	65		60
46	70		77
46	75		94
46	80		112
46	85		134
46	90		162
46	95		190
46	100		218
108	60		114
108	65		144
108	70		177
108	75		224
108	80		260
108	85		321
108	90		381
170	60		180
170	65		223
170	70		283
170	75		348
170	80		428
170	85		495
170	90		600

[argaudette]

Awesome! This is exactly what I was looking for! While 180w at 60 is not huge it is still a decent effort and 65 and 70 rpm are significant increases. These numbers are impressive. Thank you for your "research", pushing 600W is no joke.

EDIT: Just noticed the drag factor is very different compared to the rower, my rower has a range of around 80 - 230 DF. The resistance assembly must be quite different that the erg unit.

[Slothful1]

I was also a little surprised by the range, and had also assumed it would be similar to my rower. I've had it for a year, so maybe I must check if it needs a quick clean. I normally use around 85 drag factor and that seems consistently around a 3-4 lever position over the past year, so it probably is OK still.

I wanted to get to 100 rpm for all the drags, but ran out of steam!

Dave

[johnlvs2run]

600 watts is quite impressive!

[Bill]

Hello,

Thanks very much for both the question and the answer - that was a big step in helping me to better understand cadence and enabled me to complete a 30min session at high cadence and low resistance getting further than before without burning my thighs out. Thankyou again.

I've asked a question in a new thread to avoid cluttering this one.

Bill

[Boooooo]

... I am wondering about the wattages that can be produced at lower cadences, 60 rpm for example.
...

Currently mine around 215-220 w (drag factor 198)

Drag factor can go higher because of the "ambient", and probably removing the metal mesh too could reach 300 watt at lower cadence (waiting for confirmation)

concept 2 indeed says
A brand new BikeErg will have a drag factor of 45 or less at a damper setting of 1 and 225 or more at a damper setting of 10.

These drag factor ranges for new ergs assumes that the machines are at sea level. Elevation has a large impact on air density and therefore drag factor. The monitor will accurately detect environmental changes and adjust the drag factor to assure accurate data.

[MudSweatAndYears]

This is what I put together - watts might have varied a bit around each number but I tried to get the cadence and power to settle on a representative figure before I recorded it.

The whole table can be captured in a simple equation: Watts = (rps-cubed) times DF times 1.04.
here, rps represents revolutions-per-second (i.e. rps = rpm/60).

[Carl Watts]

I'm using a WattBike Pro and I love it.

The combination of air and magnetic resistance allows you to set the power where you want it. Not sure why you want to be putting in high power at low cadence, mine is setup to make about 270W at 90. The only issue is if you want to sprint without the cadence going to 156 so I stuck a long lever on the air to go from 5 to about 8 and that allows you to go to about 1100W plus without maxing out your cadence.

Personally I would not buy a BikeErg. The WattBike is permanently calibrated as it uses a loadcell on the chain and its pretty accurate. When you use Zwift you need an accurate power meter and cadence measurement as the two key elements, the rest is optional to make the ride more realistic if you want it. Sometimes simplicity rules, it connects to Zwift buy just turning it on and I just don't need the untold gears and its rock solid when you sprint.

I service the WattBike Model B monitors here in New Zealand and have also seen and repaired the WattBike calibration machine.