Newton+ CDA analysis with Isaac 1.08
Posted: Wed Nov 07, 2012 3:52 pm
Tried the "new" Cda analysis with Isaac 1.08
Have spend lot of time to get the Wind Scaling correct. 1.05 seems to be the correct number for me. (this is the middle number from 6-8 cal rides, from 0.98 to 1.08)
When analyse the CDA from lots of different rides I find this correlation between cda and speed.
At 40km/h cda is around 0.40
At 35km/h cda is around 0.35
At 30km/h cda is around 0.30
Lower cda with lower speed. Have also noticed this in the newton display.
I use a 0.006 crr for my MTB tires and 0.36 for cda.
Why different cda with different speed? Wrong tire crr or wrong Wind scaling?
One other thing. Please Velocomp, double the view time (or more) for cda in the Newton+ display. Really dangerous wating for the 2-3 sec the cda number shows before it dissapear while coasting.
Norbike
Have spend lot of time to get the Wind Scaling correct. 1.05 seems to be the correct number for me. (this is the middle number from 6-8 cal rides, from 0.98 to 1.08)
When analyse the CDA from lots of different rides I find this correlation between cda and speed.
At 40km/h cda is around 0.40
At 35km/h cda is around 0.35
At 30km/h cda is around 0.30
Lower cda with lower speed. Have also noticed this in the newton display.
I use a 0.006 crr for my MTB tires and 0.36 for cda.
Why different cda with different speed? Wrong tire crr or wrong Wind scaling?
One other thing. Please Velocomp, double the view time (or more) for cda in the Newton+ display. Really dangerous wating for the 2-3 sec the cda number shows before it dissapear while coasting.
Norbike