Very unlikely. The mountain passes in Colorado are almost always open by June.
No.
The major passes may be open - -
But if the OP wants to ride back roads, those are likely to still be closed.
Especially if the coming winter is a heavy snow winter.
I did a closed Schofield Pass in late June back a few years ago.
I had to chop my way thru multiple avalanche chutes.
Exhausting, scary, and not very smart.
<<<>>>
Not sure what the OP's time frame is -
But I would suspect needing 3 weeks for MSP-SFE, 2 1/2 weeks for SFE-YEL, and 2 1/2 weeks back to MSP.
Add a week in Santa Fe and another week in Yellowstone and that is 10 weeks.
So, either direction it will be late June for the Colorado Mountains.
Clockwise, it will be mid July for Yellowstone - - and very busy.
OP should expect some killer headwinds in western Kansas, Okla, and eastern NM.
Windwise - - probably better to ride counter-clockwise.
(Predicting winds is imprecise at best, crazymaking if you are counting on tailwinds.)
Thanks to everyone for your input.
10 weeks is precisely what we’re looking at, including one week stopovers in Santa Fe and Yellowstone. My wife’s calendar is such that Santa Fe needs to be the first layover, so we will be going clockwise. I’m from Missouri, and I went to school in Central Kansas, so I understand that heat, humidity and wind just are what they are. I’ve learned that trying to outsmart the weather usually leads to disappointment and frustration, and those two combined are often more exhausting than the actual conditions. So we’ve picked our direction and we’ll just ride into whatever comes.
Also, because of what I’ve been reading, we are rethinking Route 66. We are less into nostalgia than safety and scenery, and it seems R 66 is built around the former. So, we’re looking again at Katy Trail east to west to Clinton, MO, then the Flint Hills through Kansas and on to Santa Fe. Would be grateful for more tips for a safe and scenic route from that A to B. Jamawani was kindly supplied us with a great route from Taos, NM, to Jackson, WY (and I’m assuming the only way to Yellowstone is to continue north on 191, but if anyone wishes to correct that assumption with a better alternative…). Getting from Santa Fe to Taos is still a puzzle. Getting from Yellowstone back home is pretty cut and dried.
Again, thanks so much for all your help!