I have a survey measured piece of road, around 200m long with a straight 1.1% slope. (new road, I was the project leader)
I often ride this slope when out on my bike. When I start my ride iBike shows me 1.1% slope both ways, but then something happens. I guess it is the 5min auto tilt, because when coming back I maybe see 1.8% riding up and 0.6% riding down, have also seen up to 2.1%.
The tilt is always correct 0.0% at my marked spot in the garage when re-checking the tilt. (Not any point doing cda tests when this error occurs. At 30km/h, a difference in slope from 1.1% to 1.8% and the cda will increase from 0.35 to 0.50). I have also seen correct cda numbers in Newton when coasting the first 5 min in a ride, but after two or three runs down a slope the cda starts floating away, after around 5 min's...
My questions.
1. When I get these errors, is there any way to adjust this afterwards in Isaac? I mean changing the slope back to 1.1%, because I know it's the correct number?
Have tried fiddelig with the profile in Isaac and changing riding tilt, but without any luck.
2. I see other people also have issues with the 5min auto tilt. I use mine now on a MTB with rigid fork (but with 2.0 tires with 33psi in front).
Any plans making the 5min auto tilt to an RACR on/off feature?
Adjust "errors" in slope after a ride
Re: Adjust "errors" in slope after a ride
Just a tiny question. Why dont you simply say that independently from the speed the difference in slope from 1.1% to 1.8% equals to a change of 0.007 in Crr? I mean a measurement error in slope can be corresponded easier with an error in Crr than in CdA?NorBike wrote:At 30km/h, a difference in slope from 1.1% to 1.8% and the cda will increase from 0.35 to 0.50).
Re: Adjust "errors" in slope after a ride
Because with Newton+ Isaac can calculate Cda when coasting down a descent. I wanted to enlighten what an error in slope can do with this measurement.
Re: Adjust "errors" in slope after a ride
Aha, understood. Thanks for the clarification.NorBike wrote:Because with Newton+ Isaac can calculate Cda when coasting down a descent. I wanted to enlighten what an error in slope can do with this measurement.