K a xa k Tru vele rs%Pause for Tour Of } elloivstoneGREAT FALLS, Mont. A P -Two former Air Force men hitchhiked into Great Falls Tuesday, parked their kayaks and took a tourist's detour to Yellowstone National Park before resuming a transcontinental river trip.Jim Curnes, 23, of Wheeling, W. Va., and John Davidson, 21, of Carlisle, Pa., planned to head down the Missouri Riverearly next week.They paddled 530 miles up therivers to Kamiah, Idaho. From there, they hiked GOO miles to Missoula and caught a ride to Great Falls.After a tough upstream pull on the Clearwater, they abandoned plans to travel the Clark Fork River from Missoula to Garrison. The} had wanted to portage over the Continental Divide and reach the Missouri River near Helena.Curnes and Davidson hope to reach Chesapeake ba} by late October after paddling the Mississippi, Ohio, Monongahela and Potomac rivers. They started May 19.