Carbonda 505 or 696?

[Noctiluxx]

I’m ready to order one of these frames and build it with Ultegra 2x hydro, and 650B wheels with 47mm tires. Is there a reason to buy the 696 over the 505 since the latter excepts 47mm tires on 650b wheels? I realize the 696 has a more relaxed geometry with wider tire clearance.

[wheelsONfire]

Which size would you buy?

How much drop would you have?

How long stem would you use?

I am 181-182cm, ride Large UP, 10cm stem + Salsa Cowbell handlebar.
MTB shoes and pedals.
Sometimes swap fork to Lauf Grit. But the standard fork and 650B + Spotted Cat are much more nimble.
If you sneak into more light MTB terrain, Grit is prefered.

What kind of rides?
(this is really what you need to figure for sake of tire clearance)

Like gravel and tougher gravel or more like road and some milder gravel roads?
50-52mm tires are great. Like Vredestein Spotted Cat superlite 27'5/650B*2.00
If you ride these on 650B tires you can easily modulate tire pressure.
These are my favorite over 10-12 pair tires and combos.
Use two wheelsets; No Tubes Avion Pro for 700C tires and DT Swiss XR 361 (27'5) rims, CX ray/ DT swiss spokes, brass nipples and Hope RS4 centerlock.
Used Ryde 22 rims previously. Crap,... 1 month borth rims uneven to a point rear wheel bumped right left between chainstays.

Anyway, 650B tires are superb for real gravel. 700C tires in mud or wet cut down too much.
Low knob, fine thread 650B tires is your best option!
There are fast 650B tires too, so i would say, from 47mm and upwards is what you would ride for 650B.
The idea of + 40mm 700C tires sounds interesting. I sadly can't go bigger than 42mm due to the seatmast tube/ BB junction.
The height of the tires is the problem on UP.
I would say, for 2.1 tires, that is for sure max you can fit on UP.
Schwalbe Rocket Ron 2.1 does not work. There is no clearance to chainstays.

Last thing, if you never have been a tire nerd / addict... now for sure you will open that door big time.