Yep scarth gap is part of the 3 passes route. There’s a fair bit of hike a bike up, but also there’s a fair bit thats rideable up if your fit enough. Scarth gap, blacksail, styhead descents are all rideable this way round(riding level dependant, its a techy lakes rockfest). Scarth gap into Ennerdale isn’t as good as the other 2 but it’s still good. Folk often tag in the bridleway on the south of fleetwith pike(warnscale bottom) to make a full day of it, you go up past the Honister slate mine to access it.