Trainer Coefficients

[ldmitruk]

HI all,

Once again it's time to set up my bicycle torture chamber and mount my wheels on my trusty Vomitron® I've been looking at the coefficients for the Kurt Kinetic Road Machine and to set the value for D to 0.019168, which according to this thread over at Cycling Forums is the more up to date value. I can enter the value fine but when I save the new coefficients the value for D is presented as rounded up to 0.0192. It doesn't seem like lots but I think it might have an effect of slightly higher readings. (Geeze I'm starting to sound like someone from the Wattage Group)

Anyhow I have tried reseting the number of decimal places via the control panel and restarting Issac but this didn't change the behaviour. So I'm guessing this is the default behaviour of the software. Any chance of getting this adjusted or is there another work around I could use.

Cheers!

[Velocomp]

There's no doubt the Wattage Forum would be proud of you!

We're talking about a (potential) rounding error of .000032, or 32 parts out of 100,000. I say "potential" because it may be the case that the exact coefficient is being saved by the SW and FW, and that the size of the field displayed in the SW "only" goes out to four decimal places. If so, then the coefficient would be rounded up in the display field only. I don't know that this is the case, but it's not worth investigating.

Why? Just for fun, let's suppose that this coefficient is rounded too high by 0.000032. At 19.2 mph on your trainer, the coefficient rounding error would cause a 0.23W "error", 236.82W vs "actual" 236.59W, or a .09% error.

It's nothing to worry about...