If you want to get a bit more technical, I reckon that:
On the old MTB cable disk jobbies you have to put the pads very close to the rotor, hence, even the slightest misalignment causes disk rub. Also, on flat bars you use the full length of the lever when you press it. What it translates into, is a huge amount of leverage when you brake.
Road brakes pull half the length of the cable compared to V-brake levers, which gives you ~ 50% of your MTB force. Furthermore, you don't use the full length of the brake lever when braking from the hoods, so now you're down to, say, 25% of MTB force. And some cable pull does indeed get lost in the compressing cable housing, so you might as well be down to 15-20% of the MTB force.
If you limit your MTB lever to 1/4 of its movement, you'll never get the MTB disk caliper to work well, because even on a good day with 100% lever movement you have to set the pads really close.
Add losses in braking efficiency from slightly mis-aligned calipers, pads, rotors and you don't even get a speed modulator, never mind a brake. At least the buggers squeal so bad that everyone can hear you approaching.
A road disk caliper should therefore, have a completely different mechanical advantage to an MTB caliper. It just looks like the manufacturers never bothered with proper design & testing because there's no money in it. They must have changed it slightly by whatever ratio they picked, and never refined to the point of them actually working.
I am curious, however, that your travel adapter trick didn't work.
On the old MTB cable disk jobbies you have to put the pads very close to the rotor, hence, even the slightest misalignment causes disk rub. Also, on flat bars you use the full length of the lever when you press it. What it translates into, is a huge amount of leverage when you brake.
Road brakes pull half the length of the cable compared to V-brake levers, which gives you ~ 50% of your MTB force. Furthermore, you don't use the full length of the brake lever when braking from the hoods, so now you're down to, say, 25% of MTB force. And some cable pull does indeed get lost in the compressing cable housing, so you might as well be down to 15-20% of the MTB force.
If you limit your MTB lever to 1/4 of its movement, you'll never get the MTB disk caliper to work well, because even on a good day with 100% lever movement you have to set the pads really close.
Add losses in braking efficiency from slightly mis-aligned calipers, pads, rotors and you don't even get a speed modulator, never mind a brake. At least the buggers squeal so bad that everyone can hear you approaching.
A road disk caliper should therefore, have a completely different mechanical advantage to an MTB caliper. It just looks like the manufacturers never bothered with proper design & testing because there's no money in it. They must have changed it slightly by whatever ratio they picked, and never refined to the point of them actually working.
I am curious, however, that your travel adapter trick didn't work.
