Originally Posted by
zacster
I tried riding Haleakala on Rouvy today, starting at the switchbacks. I didn't even make it up one mile! The grade in Rouvy was at 12% but I don't remember it being that steep. Also the higher grade started on my trainer before it appeared on screen so I wasn't quite ready for it.
12% doesn't jibe with my own experience there or this chart:
https://veloviewer.com/segments/638944
EDIT: Actually, looking closer, there are some kicks to that 10%+ range there on the switchbacks. If you turn on "Gradient" markers in that page, you can see them - they're all like 10-50 meters, but they are there.