Carbonda lists the max tire width as 2.35" for both the FM936 and FM909...but 2.4" for FM1001.  Tire widths are nominal, and there is a lot of variation in how wide they inflate on rims of differing widths.  For anyone running 2.4s, which tire are you using, what (interior) width rim, and how much clearance do you have to chain and seat stays?

Are there any MTB hardtail frames that can support large chainrings e.g. 40t?  Non-boost spacing would be preferable.

I am considering the idea of building a flat bar road/gravel bike, but am having trouble with the geometry of my options.  Road/gravel frames have a short reach/TT because the long stem and drop bars lengthen your torso to where it needs to be.  My hoods are 130mm farther out from my stem.  I could make that up through a combination of longer TT, longer stem, and conceding a little distance.  However, the only easy way to get a longer reach is by buying a mountain bike frame.  Ignoring all the minor problems with that, the lack of support for large chainrings is a deal breaker. 

So back to gravel frames.  Something with a sloping top tube and the shortest seat tube...then buy the largest size so I get the longest reach/TT possible.  There isn't anything obvious that makes the math work well.