Icicle Ridge Tr1570 can be an OAB, with a ridgeline ascent only suitable for the most aggressive hill climbers.
Leavenworth is well-known for biking, but not because of Icicle Ridge Tr1570, or nearby Freund Canyon Tr6701 for that matter.
The real epic rides are in the Chelan and Entiat mountains, some as steep as Icicle Ridge Tr1570 but with miles of ridgeline to ride instead of being so brutally short and steep.
Icicle Ridge Tr1570 is actually less steep than Fourth of July Tr1579, so a loop ride should still start with Icicle Ridge Tr1570.
Ding: Just too steep for most riders, which means the trail doesn't get much use and may not be rideable in years when the forest service is not around to chop up fallen trees and such.
The two trailheads are easy to shuttle, to avoid the FR76 downhill return, but anyone up for this much vertical probably won't even notice the 8mi FR76 return.
The nearby Stuart Range and Chiwakum Mountain wilderness areas offer hikers some really epic options.
Fourth of July Trail 1579, Icicle Ridge Trail 1570
Badlands Trail 1576, Chatter Creek Trail 1580, Chiwaukum Creek Trail 1571, Colchuck Lake Trail 1599.1, Glacier Creek Trail 1573, Hatchery Creek Trail 1577, Index Creek Trail 1572, Painter Creek Trail 1575
Aasgard Pass Trail, Eightmile Lake Trail 1552, Eightmile-trout Creek Trail 1554, Prusik Pass Spur Trail, Snow Lakes Trail 1553, Stuart Lake Trail 1599
Leavenworth Ski Trails
Bridge Creek Campground, Eightmile Campground
Ranking consistently applied to all of the listed trails.