Or maybe you could try to stretch the spring a little, so it will put more force on the assembly

The 58 is huge though, do you need the extra toe clearance?

Nice, I tried to get them to do measurements with no luck. Yeah maybe the best option is to go for a nominally smaller tire with the really wide rim .

I pulled the trigger, and bought a Chameleon one in size 56. Really excited about it. Going to build it up with 11 sp mechanical Ultegra, and hoping to fit 50/34 chainrings on there. It's going to be my do-it-all bike with a road and a gravel wheelset.
 Unfortunately, it won't show up for another 2 months  (EU preorder for June 30).

A few things:

1) The reason it has similar geo to the BXT and Nextie, is that all 3 are very heavily "inspired" by the Scott Addict Gravel. That's also why I'm hoping 50/34 will fit, since that fits on the Scott.

2) When it comes to the setback, what matters is that we can achieve our preferred saddle position relative to the BB. This in turn can be determined from just 2 factors: The seat tube angle and the setback relative to the line through the bottom bracket. The reason the setback looks big is that the seat tube is shifted forward relative to the BB as seen by the blue line.

i) My current bike has a STA of 73.5 instead of 73 on the Graro. That results in shifting the saddle back roughly 5mm at my saddle height, relative to my current bike.
ii) My current bike has a setback of maybe 5mm, (round seatpost centered on the BB). This means another net 15-5 mm = 10mm setback.
iii) However, the clamp that holds the saddle rails is also much smaller on the Graro, which gives a bit of leeway the other way (roughly 7mm by my estimation).


I've concluded that I can easily achieve my current saddle position, even without slamming the saddle all the way forward.

Will definitely post a lot of measurements related to tire clearance, chainring clearance etc when I receive the frame!