Supposedly, Simple Green, if used in excess and not removed from the tire, can act as a tire softener.
Awesome, thanks for that info. Windex doesn’t seem to have that effect?
This is related but slightly off topic.
I was told to spray my rain tires with Windex and then wrap them in plastic film. This tells me that when may not be harmful but benefit the tires…
I have successfully used wd40 when the tire would not seat with soap. Typically I use a few cap fulls of dawn diluted with water in a small spray bottle.
From the MSDS.  There are a couple things in there bad for rubber. If you’re mounting tires for a weekend and using them up, I don’t think it matters.
Based on all the comments, I think this is the way to go.
There is definitely a big difference between spraying a tiny bit on the bead surface and it evaporating in 60 seconds vs. Soaking the contact surface and wrapping it in plastic wrap. Even if it doesn’t end up affecting the performance the intent to do so was still there….
I like using Yamalube tire mounting spray - not messy and works well.
Absolutely nothing now…never have an issue mounting a 7 tire on a 7 rim.  Now when you start putting 6” tires on 7” rims… I have used WD40 or water based cleaners for 206 mounting.  Best bet was to make sure its all warm, and then its easy.
   I have used WD40 or water based cleaners for 206 mounting.  Best bet was to make sure its all warm, and then its easy.

