When we drove the Beartooth, there were throngs of mountain bikers (sometimes 8-10 abreast) which dictated how slowly (very very slowly) vehicular traffic was moving. There were limited opportunities to pass, and when we were able to pass one pack, we would quickly run into another. I don't know if there was some event happening that day, or if summertime mountain bikers are a regular feature. Not that this answers the OPs question, but the idea of hauling a 5er up and down, and having to cope with the bicyclists would give me pause.