I do a "big ride" every year leaving from Washington State. Last year I did the lower 48 in 16 days. I always leave the day after Labor Day. The weather is great in the Northwet (not a typo LOL) and starting to cool down in the South. Also, much less traffic because the vacationers are mostly gone because school has started. You don't want to hit the Northwest until July if want weather you can depend on. If I were riding your route I would head North and then West, finishing up the Southern states toward the end of September.

 

Great question.
In for answers.
May be luck of the draw.

Summer 100 degree heat. Spring snow ice residue. Winter I say no. Fall could be cold + unpredictable weather.
Is there a 30 day envelope of so called perfect motorcycle traveling weather?
OP's route seems to indicate almost a four corner ride of the USA.
I'd guess May 01 to 30.

 

 

Time your trip to run back East with us, we leave Ontario California May 15th . www.rftw.us

 

Even as uncomfortable as it is riding in 100+ degree weather you can do it is you stay properly hydrated, take frequent breaks and possibly use "cooling vests".

Cool/cold temps and rain can be managed with heated and rain gear down to a certain point and that is your call but one thing that you cannot ride through is snow and in the higher elevations it is quite possible in some places in June and even into early July.

If I was planning a trip like yours (JMHO) I think I'd plan on the southern part of the trip in mid-to late June and then head north and east as time and weather allows.

Just be sure to watch the weather forecasts every chance you get and lay-over when you have to and ride like H**L when you must!

With 30 days, you'll have time to see a lot of beautiful scenery and to be safe while you're doing it.

Careful with the trailer. Be sure the tires are new when you leave and that you have "buddy bearings" in the hubs and take a mini-grease gun and check your tire pressure and give the bearings a shot of grease frequently. Another thing with the trailer is not to take the "kitchen sink" with you. Take only the things that you know you'll need. You may need that unfilled space for "collectibles" that you purchase during your trip.

Keep us informed

 

 

The last time that we did a tour we left Atlanta the weekend after labor day.We rode to Seattle, Reno , Vevas,and the Grand Canyon. We were gone for 19 days and never put on leathers or rain suites. A good time was had by all.