There's a highway crossing central labrador. Here's a web-site about it and generally about travel in Labrador and Newfoundland. There's maps and lots of travel pictures. His sounds like fun:
" . . you can now do a circle tour from Baie Comeau (Quebec), north to Labrador City, east across to Goose Bay, down to Blanc Sablon via Cartwright, take the ferry across the Strait of Belle Isle to Newfoundland, drive south down the west coast of Newfoundland to Port aux Basques, from where you can take the ferry across to Nova Scotia."
Been to Newfoundland and it's great. Green, scenic, great little villages on the seashore. Went across to Labrador on the ferry and rode the 55 miles of paved road that exist there. Not green but barren instead. Stayed in Blanc Sablon and rode to Red Bay where the pavement ends. Look at the photo on the home page of your link. That's where the gravel starts in Red Bay. I rode a little of that gravel on my two-wheeler. It was not like other gravel I've been on -- it was like riding on marbles.
Here are just a few quotes from the website that you provided:
"From a practical point of view, the highway consists of two parts as well:
paved and
gravel. And after traveling the entire route from Baie Comeau to Goose Bay and back on about 1600km of gravel road, you will never again take paved roads for granted!!"
"From Baie Comeau to Manic 5 (212km) the road is paved, but it is twisty, narrow, and very hilly, with no real shoulder. No gas until the Manic 5 dam, 212km to the north.
Please remember above all, that although the Trans-Labrador Hwy has been rebuilt as a modern gravel road, it is still a very remote area, with as much as 290 km between gas stations and other services."
"This is a raw, purely practical road. It is definitely not a scenic parkway for tourists. The road was built for transportation alone. There are no scenic pullouts, no rest areas, no campgrounds, and very little signage to help guide you. You can camp wherever you want (well, perhaps not officially, but I did), and this usually ends up being in the old gravel pits that were used to build the road."
"If the road is dry, expect a complete whiteout from the dust after a truck passes you. Slow down and pull to the right as far as you can safely go. This will help preserve your front windshield (from flying stones), as well as keep you out of the way if the oncoming driver does not pull over to their side of the road far enough. And watch out for another vehicle following the first, suddenly appearing out of the dust cloud. Watch for graders that are continually working on the road."
Study the website and investigate the internet thoroughly if you're at all serious about it. There are many trip reports from the serious dirt-bike riders and adventure-bike riders who have done the road and can provide the motorcyclist's perspective. Also note that if you take the ferry from Blanc Sablon across to St Barbe, Newfoundland and ride from there south to Port Aux Basques, you miss most of Newfoundland. In my opinion, that would be a real shame. You're on the northern peninsula when you get off the ferry from Blanc Sablon. Good things there -- go north to L'Anse aux Meadows World Heritage Site where the Vikings landed about 1,000 AD. Very interesting. Then return south past the ferry point and pass thru the fantastic Gross Morne National Park. But then when you hit the TC-1, look at how much of Newfoundland is east of there. The main part of the island. North of the TC-1 on the north shore of the main part of the island are many little seaside towns and back roads. And eventually you can end up in St John's which is a very cosmopolitan city seemingly "at the end of the world". From there, you either turn around and go all the way back across the island (fairly quickly on the TC-1 if you desire) or go SW down to Argentia and get the 14-hour ferry back to North Sydney, Nova Scotia.
If you just go from St Barbe down to Port Aux Basques as described on the website, you miss L'Anse aux Meadows as well as everything in the main part of the island.
Just some food for thought.