I recently changed my stem to a longer one, but still had the same angle. I did a short cal ride and adjusted my wind scaling in my profile to match the new cal ride one. I was then having issues, (actually was having them before the new stem) with either really low numbers on downhills and even flats so I made adjustments by doing coast in the coast screen to try and get my numbers to be around zero while going at around 27-30 mph. I then started getting to high of numbers after the stem change so I did more test in the coast screen and adjusted my aero as needed. I am now not so confident that my profile numbers are even right. Could someone please look at my last ride file from tonight and see if I screwed up my profile? I attached my last ride file from tonight. Thanks so much for any help.
Clint
Something is still off in my profile. Please help
Re: Something is still off in my profile. Please help
I don't see anything obviously wrong with your ride file. Since you don't have a cadence sensor I can't tell when you are coasting. When coasting your watts should be close to zero--that's a good way to check to see if your drag coefficients are correct.
Your wind speed looks reasonable. You show a slight tail wind for the ride; this might be the case, or you might have been in some traffic, or you might have been riding some with a group. I can't tell.
Your CdA and Crr numbers look very reasonable.
If you want to use coast downs, the best sequence is to perform a Cal Ride, then 3 to 5 coast downs immediately thereafter. Also, no more than 30 minutes before your Cal Ride/coastdowns, you need to do a new Tilt Cal and Wind Cal. Finally, after having done all these steps, you need to use your iBike software to analyze your Cal Ride and coast downs.
Unless you follow these steps, in order, you will not good results from coast downs. This is why, for most riders, we recommend using the "Fast Start" sequence, followed by a short Cal Ride, and skip the coast down step.
Here is a link to the coast down instructions, which are on pages 43-45 and 69-74 of the iBike instructions.
http://www.ibikeforum.com/viewtopic.php?f=12&t=1507
For your iBike you can reset things by doing a Fast Start and Cal Ride. See if that gives satisfactory results. If you then decide you want to try coast downs, you'll need to do another cal ride, followed immediately by coast downs and by software analysis.
Your wind speed looks reasonable. You show a slight tail wind for the ride; this might be the case, or you might have been in some traffic, or you might have been riding some with a group. I can't tell.
Your CdA and Crr numbers look very reasonable.
If you want to use coast downs, the best sequence is to perform a Cal Ride, then 3 to 5 coast downs immediately thereafter. Also, no more than 30 minutes before your Cal Ride/coastdowns, you need to do a new Tilt Cal and Wind Cal. Finally, after having done all these steps, you need to use your iBike software to analyze your Cal Ride and coast downs.
Unless you follow these steps, in order, you will not good results from coast downs. This is why, for most riders, we recommend using the "Fast Start" sequence, followed by a short Cal Ride, and skip the coast down step.
Here is a link to the coast down instructions, which are on pages 43-45 and 69-74 of the iBike instructions.
http://www.ibikeforum.com/viewtopic.php?f=12&t=1507
For your iBike you can reset things by doing a Fast Start and Cal Ride. See if that gives satisfactory results. If you then decide you want to try coast downs, you'll need to do another cal ride, followed immediately by coast downs and by software analysis.
John Hamann
Re: Something is still off in my profile. Please help
Thanks, but just so you know this was a profile that coachboyd helped me out with. I was trying to get it more accurate on the downhills by adjusting the aero which of course changes the cda. Like i said at first I was getting really low numbers on the downhills even when going really hard, then somehow I changed my profile and started getting really high numbers on the down hills. I then changed the aero again and seem to be getting somewhat better looking numbers but not so confident with my numbers which is why I am posting again. I guess on Thursday I will do another ride cal with coast downs and see what I get and go from there.
Oh, I was in a group ride for the ride file I sent. Also I did merge my file with my Garmin so there should have been cadence and heart rate to.
As for analyzing my cal ride and coast downs after, that gets confusing for me. I am not sure what is good or even bad as far as the profile numbers go, which is why I having problems right now. Thanks..
Clint
Oh, I was in a group ride for the ride file I sent. Also I did merge my file with my Garmin so there should have been cadence and heart rate to.
As for analyzing my cal ride and coast downs after, that gets confusing for me. I am not sure what is good or even bad as far as the profile numbers go, which is why I having problems right now. Thanks..
Clint
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bex
- Posts: 84
- Joined: Sun Aug 31, 2008 7:54 pm
- Location: 'twixt Sylvan Lake and Eckville in Alberta, born in Manchester England. Always an Englishman
Re: Something is still off in my profile. Please help
Can you go back to your original profile that Boyd tweaked for you.
I would "Guess" that a longer stem of the same angle would only require a new tilt setting.
At least then, you will be no worse off than before you started to change stuff.
Or experiment with your other profile setting for the same bike, that way you at least have the original settings unchanged in profile 1 (for example)
Bex
I would "Guess" that a longer stem of the same angle would only require a new tilt setting.
At least then, you will be no worse off than before you started to change stuff.
Or experiment with your other profile setting for the same bike, that way you at least have the original settings unchanged in profile 1 (for example)
Bex
Re: Something is still off in my profile. Please help
Is your wind scaling correct? You check this *first* by riding back and forth on a route with no traffic. When you get that nailed, then you can check your CdA by coasting. Of course you also need to make sure that your wind offset is zeroed, and the tilt has had time to properly adjust itself.