BigE:
OK, I done some measurements. I do not know how to classify green/blue/black, the fact is that each ski resort has different idea of what is green and what is black. But this should give you a rough idea.
To make decent turns on Carvers, as on skis you need to have some momentum going.
Whether the Carvers will maintain speed depends not only on steepness but also on how smooth is the surface. Smooth sealed asphalt makes not only for pleasant experience and less wheel wear but it helps in maintaining decent speed. So you can go with smaller pitch if surface is smooth.
Carvers will roll on smooth surface with as little as 1 deg slope. This has feeling similar to flat bunny slope and is good for tipping drills. You can make more advanced turns on such slope if you gain some speed first, but after 3-4 turns the speed deteriorates and you will be back into more conservative green run turns.
I normally state on a 3 deg pitch, just because it is the only low traffic road with relatively good surface and pitch close to my house. Turning on this is similar to easy blue run. The fun starts if I get more initial speed with skating stoke. The 3 deg pitch will maintain your speed quite well, so if you don?t mind accelerating on your own first, it will make for good all-purpose run.
My favorite run is next to my friends house, quite far from my house, and is about 4-5 deg pitch with very nice smooth asphalt. It still reminds me of a blue run, however, it is easier to make more aggressive turns on it.
Never tried anything steeper, if I find something with low traffic and good surface I will.
So probably 0-1 is bunny green, 1-2 is green, 2-x is blue, where x>5.
I know, it is not San Francisco steep, is it. I believe experienced Carver user with good wheels (they have to grip well) can make it in SF. This would probably be double black
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