I have a few 50CC Quest rides. As mentioned by others, SDO/JAX is the shortest and probably fastest. Most of mine have been SMO/JAX (because I lived near Santa Monica) which is about 100 miles greater in distance.
So leaving SMO on 14/Apr at 03:00.
There is a 24/hour (staffed) fuel station at 1801 Lincoln Blvd (Lincoln is a code name for PCH in SMO) which is close to the water and fills the requirement for a starting location. It is Exit 1 (A/B) on the 10. It is urban for seemingly 100's of miles but this is Callie so twist it and if traffic slows you can lane share.
Your GPS might send you on a brief run of the 60 through east LA/Riverside counties. Do or do no do, you can stay on the 10.
Be careful as you ride into the Palm Desert, there is a 60+ mile stretch with no fuel. Mp173, Chiriaco Summitt is a good place for fuel as this is it until you get to Blythe.
Once in AZ, you have a decision at mp 112. Take the PHX bypass or go through PHX. I always take the bypass. It adds about 11 miles but going into a big city has risks. I take AZ85 to the 8. Plus the 8 is a great road with a 75mph limit. I set the cruise at 84mph in AZ/NM.
Lots of fuel on the 10 in AZ/NM but pay attention. Western freeway speeds can consume a lot of fuel.
In NM there are so-called "safety corridors" where fines are doubled and enforcement is tripled. Slow down a bit.
At TX mp6 there is the option to take the "Trans Mountain Loop" a.k.a. TX 375. This adds 5 miles to your route and avoids 90% of urban El Paso. It is multi-lane divided the entire route. The speed limit is 55-65 but no one seems to care. The 10 through ELP is 60mph.
Once east of ELP in the mp-60's the speed limit changes to 80mph and there is not a single slow down until Kerrville (over 400 miles). This can really swallow fuel. There is plenty of fuel but pay attention. MP140, 250's, 365, 400 are all good fuel stops with multiple options. Just west of Van Horn you will enter the Central Time Zone.
As you pass by Kerrville you are in the middle west or at least not in the wide open west any longer. There will be more traffic and such for the rest of the ride.
I always take the Anderson Loop (FM 1604) around San Antonio but Houston is more of a puzzle. The SHT tollway to the south is an option (I have TXTag) but last time I did this run (2 weeks ago) I stayed on the 10. Approaching Houston WAZE is your friend.
In LA there is massive construction in Lake Charles with the 10 squeezed to a single lane. Garmin traffic management indicated a 99-minute delay - YIKES. Take the 210 bypass. It might look slow but in a couple of miles it will open up.
West of Baton Rouge is a slow zone over a swap (the whole state is pretty much a swap) with controlled and enforced speed. Be alert.
There is no loop around Baton Rouge which can be a serious shit show for traffic. Again, WAZE is your friend.
There is(was) construction in the tunnel in Mobile, AL, but there was not much traffic so good luck as there is no loop.
Once you cross into FL you are almost done. If it is dawn/dusk - there are lots and lots and lots of deer.
I use the GATE station on A1A (2520 South 3rd St, JAX Beach), staffed 24/7 and sells wine/beer until 02:00 and starts again at 06:00. Be super careful on A1A. The speed limit is 35mph and I have seen enforcement at 01:00. Easy to find, take the 10 to the 95 south and exit at Butler Blvd (a.k.a. FL 202) to the beach. Turn north and GATE is about 1 mile on your left.
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