Spey Rods for Chinooks

Chinook Salmon, also called King Salmon range around the Pacific Rim from Central California up the coast of North America into the Gulf of Alaska through the Aleutian Islands, then across the Bering Sea, down the Coast of Kamchatka and into the Northern Islands of Japan.

All tackle world record: 97-pounds 4-ounces - Kenai River, Alaska.
Fly Rod world record: (8 lb. test) 71-pounds 8-ounces - Rogue River Oregon.
Average Chinooks in most watersheds are 15-35 pounds.
In the main-stem of the Columbia River 150-years ago Chinooks may have averaged 65-pounds, with some fish weighing over 120-pounds.
According records from a hatchery in the Sandy River basin in Oregon, Spring Chinooks in the 1890s averaged much as the do today: 12-20 pounds, with Fall Chinooks averaging 35-pounds.

Whereas steelhead in most water-sheds average 6-20 pounds with 30-pound tops, Chinooks average 15-35 pounds with the larges specimens being true behemoths.  It stands to reason that Chinook tackle should be larger as well. Whereas steelhead Spey tackle is in the 6/7/8 range Chinook rods average 8/9/10 sizes.  In Chinook fishing not only are the fish larger, but the flies average larger as well, so it takes heavier lines to cast these flies comfortably.