So I have a legit question: how did post mount become the accepted standard and is it really better than IS mount?
And who legitimately runs their post mount brakes without an adapter nowadays? Those adapters are a ball ache to get the right screw length, add weight and make aligning the brakes more difficult because they always shift as you tighten the screw or they aren't correctly aligned to start with!?
Surely IS would have made more sense nowadays - you could use the same frame/fork mount for anything from 140 all the way to 220?
Same goes for the 15mm axle - I had a Lyrik with a 20mm QR maxle back in the day, simple and easy - why did we ever go backwards and standardize on 15mm, it can't save THAT much weight, and many hubs are 15/20mm convertible via end caps, so I'm not buying that bearing diameter bs excuse they made... especially seeing as fork companies are all about trying to build a stiffer fork nowadays!?
It's just funny how back in the day when they settled on 15mm they said "oh our testing showed that there isn't a significant difference between 15 and 20mm in terms of stiffness" but now when fox releases the podium, it's like "oh we had to go 20mm and steel".
I get how it's nice to have compatibility of wheelsets between different bikes, but I also kinda feel like any bike that is spec'ing a 36/lyrik or up should probably be using a 20mm axle
There have been great discussions in the tech forum about the reasons and benefits for PM vs. IS in terms of welding, frame alignment, and facing (along with 15 other reasons I'm forgetting), and you can find those if you go looking. Those most recently came up when some steel hardtail frame (can't remember the brand) came out with a road style flatmount rear brake mount inside the rear triangle, which triggered the "how do brake mounts work" conversation.
Regarding 15 vs. 20mm axles, I think we've reached forum consensus that 15mm was always a dumb idea, provides almost no benefits, and was simply a midway step to woo XC racers away from QR axles.
I run 5/6 of my brakes without an adapter (unless you count the stupid washer needed to do 203 instead of 200). But I don't count that against the PM because the stupid there is why 203 still exists and why Galfer makes Shark rotors in 203 but not 200.
You're probably not wrong on the 15 vs. 20. Running Torque Caps on my RS forks definitely feels more precise than not running them.
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