There are a couple of options to getting to Las Vegas from the ACA Grand Canyon Connector. At Ash Fork, AZ go west on I40 until you get to exit 139 - Crookton Rd. Follow Crookton Rd which becomes Route 66. Take this all the way into Kingman, AZ. Route 66 connects with Hwy 93. Take 93 north. This will take you over the Hoover Dam into Boulder, NV, Henderson NV and Las Vegas. (You could also take I40 all the way into Kingman.) I haven't been on Hwy 66 so can't say what is on that road but Hwy 93 is a divided hwy almost until you get to the Hoover Dam. There is a least one place, Dolan Springs - slightly off the hwy, where you can get water.
You could also follow the Grand Canyon Connector to La Verkin, UT. Then take Hwy 9 through Hurricane until you get to Hwy 212. Take 212 into the Washington/St. George, UT area. Then you two options. You could take I15 south of St George, through the Virgin River Gorge, all the way to Vegas or you could take the road through Santa Clara, UT (route 18 and
. This turns into old hwy 91 and dumps you onto I15 at Littlefield, AZ. Then follow I15 into Las Vegas.
Once you are in Las Vegas you want to get to hwy 160 (which is also called Windmill in the cities south of Vegas). It also the road to Pahrump, NV. Then take hwy 372 (becomes 178 in CA) to Shoshone, CA. Follow 178 into Death Valley. The road takes you past Badwater which is the lowest point in North America. You will then run into hwy 190. Follow this north then west to hwy 136 to Lone Pine, CA and hwy 395. You can then take this North to hwy 120 in Lee Vining. 120 will take you over the Sierra Mtns into Yosemite. Be aware that the mountain road/passes are closed in the winter time as they are not plowed/maintained. If you arrive in the winter you will have to head south on the 395 until you get to hwy 58 (not sure if hwy 178 is open in the winter) and go through Bakersfield. You can then head north to get to Yosemite. After Yosemite you have a couple of other options to get over to the coast so you can follow Hwy 1.
In Death Valley a map may indicate that you can take Racetrack Valley Rd and Death Valley Rd to leave the park. I DO NOT recommend this road. It is a poorly maintained dirt road that will see you pushing your bike through 6 inches or more of sand. It can be a little dicey with a four wheel drive vehicle. There is absolutely no water stops or shade. You might see 1 or 2 vehicles if you are lucky.
As was said earlier carry plenty of water. There are some spots where water stops are few and far between.