my logic with cable disc brakes and why they don't work well on drop bar levers, am i right?

[jonnyboy666]

ok, cable disc brakes on gravel/road bikes, they suck, they have pretty much sucked since they were first used, but am i right in thinking this:-

back in the day, road drop bar levers worked with road caliper rim brakes and cantilever rim brakes, mtb levers also worked with cantilever brakes, this means they had/have the same cable pull, in the mid 90's V brakes came out, you had to have a brake lever that pulled more cable to properly activate a V brake, this meant that drop levers then didn't work with V brakes, then we started seeing disc brakes, now when cable disc brakes entered the MTB market, the first complete cable brake i saw was from Formula, a really basic brake, it was designed to run off a V brake lever . . .

so cut to the gravel bike stuff we have now and if you get a shimano or Sram lever and connect it to a traditional road rim brake caliper and it feels lovely, connect it to a cable disc brake and it's spongey as hell and the lever comes most of the way back to the bar, just like if you connected a V brake to a cantilever brake lever back in the day.

does this make sense? am i right? is the issue with crappy braking on gravel bikes simply down to the fact that the people that spec the bikes have forgotten that technically the levers and calipers are not compatible?

i said this to a rep the other day, he thinks i'm right, it's something i have mulling over for quite a while

thoughts?

 

[foz]

Possibly, but there are cable disc brakes designed specifically for road levers so shouldn't be an issue....

 

[BerthaPog]

I thought there were different cable disc callipers for road/canti cable pull vs “v-brake“ cable pull.

eg For road/canti cable pull vs For v-brake cable pull

or have I misunderstood?

 

[jonnyboy666]

@foz yes there are, but no company seems to spec them! most gravel bikes get a basic tektro or basic shimano caliper, these were designed for mountain bikes and hybrids, sram did do a couple of options on brake arm length on their calipers but i still saw a mix in terms of spec on bikes, it was like "oh this one seems good!" next time you saw that set up on a similar bike it felt horrible! no consistency. they all seem to suffer from a lack of power, most are spongey as hell and come back to the bar, all need regular adjustment, as in literally every ride, obvs i think they for the most part completely suck, but is it a mistake of the people that spec them not being old enough to know that V brakes levers pull a different amount of cable to a road/canti lever?

 

[jonnyboy666]

@BerthaPog i built a bike yesterday with the road caliper you have just linked to, they suck, and they are on a brand new bike with Sram levers, i also had a pair come on my bike that were linked to shimano sora levers, spongey, lever back at the bar etc, minimal power, it's just not good enough, changed to GRX straight away.

 

[minor_LEGEND]

If that was the case they'd be spongey as hell? Are they? In my case the TRP spyre with Tiagra 4700 STI feel fine - but are just garbage for another reason.

(edit) I didn't read the prev post. However my Spyres feel OK & work reasonably with sintered pads in prolonged dry weather, but are abismal when moisture enters the equation & are lacking when pulling up from high speeds - I am lightweight so this would only be worse for heavier rider/laden bike.

 

[BerthaPog]

@BerthaPog i built a bike yesterday with the road caliper you have just linked to, they suck, and they are on a brand new bike with Sram levers, i also had a pair come on my bike that were linked to shimano sora levers, spongey, lever back at the bar etc, minimal power, it's just not good enough, changed to GRX straight away.

Maybe they are just pants, regardless of cable pull.

 

[jonnyboy666]

@minor_LEGEND yes the sram connected ones are spongey as hell, i didn't feel the sora ones were much better, neither have great power.

@BerthaPog yes, utter pants.

 

[hawkhill97]

I've used Avid BB7 road brakes with Shimano road brake levers and they were really good. I'd definitely use them again on a build.

 

[minor_LEGEND]

TRP spyres is seen as the best for road/cable operated option. I have literally just bought some used, early Ultegra post mount (785?) series calipers & levers to ditch the cable operated setup on my Commuter/winter bike once & for all.