Can multiple cal rides be done on the same day? For example, can I do option 1(Estimate CdA and Crr) which requires no coast downs, Then follow that with another Cal Ride using Option 2 (Measure CdA and estimate Crr) and do at least 3 coastdowns. Then follow that with Option 3 (Measure CdA and Crr) and do at least 5 coastdowns.
A companion question: In Central Texas "Hill Country" it is difficult to find a stretch of road that is flat. The best place I have found is one road which has a long curve about midway (so long it is almost straight) and even that road has quite a few ups and downs. The problem is the road is so smooth that I am getting a Crr of about .0038. Frequently, I ride on chipseal or something akin to it. Should I just go with the .0055 for Crr or try to find different road that is closer to the typical rode I ride on?
Thanks for any help.
Multiple Cal Rides
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stevevarnum
- Posts: 6
- Joined: Tue Mar 03, 2009 12:34 pm
Multiple Cal Rides
Steve Varnum
"Kites rise against the wind...not with it." Joe Friel
"Kites rise against the wind...not with it." Joe Friel
Re: Multiple Cal Rides
IMO if you can get a good CdA from that stretch, then just boost your Crr to better reflect the roads you ride on.
If you can nail your wind scaling and get Crr about right, then you can always check the accuracy of your iBike's CdA by coasting while at a fairly high speed (>20mph).
If you can nail your wind scaling and get Crr about right, then you can always check the accuracy of your iBike's CdA by coasting while at a fairly high speed (>20mph).
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lorduintah
- Posts: 664
- Joined: Fri Jan 11, 2008 9:37 am
- Location: Plymouth, MN
Re: Multiple Cal Rides
I'd keep the values from the rides you have already done. As rruff says, just change Crr and boost it a bit for changing roads. The rolling resistance is only going to contribute a small amount to the power needed and for any given road and tires, etc., it is a small contribution to keeping a pace of 18-25 mph. If you are only going 8 mph, it might make a difference - but if you live in the Austin area, I doubt that you get out on the roads only to ride at that kind of speed.
You probably should never need to go above 0.060 unless you are riding on dirt if you are getting 0.038 right now. You can also post process rides by changing the Crr in an edited profile and apply it to a ride afterwards. If you change Crr by 0.01 from what was originally used - see how much of a difference you get...
Tom
You probably should never need to go above 0.060 unless you are riding on dirt if you are getting 0.038 right now. You can also post process rides by changing the Crr in an edited profile and apply it to a ride afterwards. If you change Crr by 0.01 from what was originally used - see how much of a difference you get...
Tom