Have ridden to Alaska from Texas four times now, any bagger, cruiser or road sofa can make it, no problem. Yes there will be road construction with gravel sections, but not miles and miles of mud and stone. When you come to a construction section with waiting traffic, motorcycles go to the head of the line to follow the pilot vehicle. If you should happen to drop your bike there, everybody will help get you going again so the other vehicles can get through. Going north of Fairbanks to the Arctic Circle and Prudhoe Bay, you will encounter miles ands miles and miles of gravels and mud. A dual sport bike is better suited for that, but there have been cruisers who made the trek, if they were lucky enough to catch a dry spell with dry roads. And yes, every year several riders are killed on the Dalton Higheway to Prudhoe Bay. Though, most accidents are on the return ride coming back when they are over confident and in a hurry. The Governor of South(?) Dakota wrecked his bike, broke his legs returning from Prudhoe Bay several years back.
Your biggest challenges will be keeping your speed down and closed gas stations. The road has many blind curves and hills with limited sight distance, animals graze along the roadways and cross it frequently. Loose sand, mud, rocks and boulders find their way to the pavement after a heavy rain. Do not expect to ride your normal 70 mph up there. 55 is more the norm because of the conditions.
Just because there is a gas station shown on the Milepost map, there is no guarantee it is still open. When you get down to half a tank, start looking for a station. Carry a spare gas can.
If you haven't yet, get a currently copy of The Milepost. If has all the information you will need, from gas, motels and food stops to things to see along the way. The biggest mistake riders make is not allowing enough time to enjoy the trip. If you only have a two weeks vacation to ride up and back, you won't see anything but the road in front of you.
Was planning a fifth ride up for last summer, then Canada closed their borders. Will go this summer if they open up.
Be glad to answer an specific questions, shoot me a PM.
CCjon