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Rotor size has no effect on the maximum loading on the fork
If the caliper is further away, there's more leverage on the mounting post, no? I'm genuinely asking because physics was lost on me at school
The limiting factor is how big a brake disc you can fit before it hits the inside of the fork leg. It's a geometric limitation, not a strength limit.
On fork legs that taper, I get that. But on a straight legged suspension fork, the rotor will never touch no matter how large a rotor. Yet there's a maximum spec'd size from the manufacturer. I appreciate I'm including all forks in this debate, road and MTB
TooTallTim-
If the caliper is further away, there's more leverage on the mounting post, no?
Or is it the same because you’re not changing the force that you’re braking to a halt? You’d still have the same rider + their same velocity, just a longer lever, so the forces farther (further is for metaphorical distance) away from the hinge would decrease, but the same force would be applied to the hinge.
Well now I’m confused and still sober :/
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If the caliper is further away, there's more leverage on the mounting post, no? I'm genuinely asking because physics was lost on me at school
The longer lever works both ways. It increases the mechanical lever operating in the caliper mounting points. But it also decreases the force needed to be exerted by the caliper due to the additional mechanical advantage. In the end it all equals itself out.
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There’s more leverage on the adapter if you make the adapter longer, but the torque going into the fork legs is the same. I’ve never seen the mounting points on a fork fail before an adapter.
Eseman
Brommers
chiroshi
Indeed. Rotor size has no effect on the maximum loading on the fork, on any bike where the brakes are powerful enough to lock up the front brake. Anyone who disagrees should immediately go out and buy L-shaped cranks. The limiting factor is how big a brake disc you can fit before it hits the inside of the fork leg. It's a geometric limitation, not a strength limit.