Disc brakes on road bikes

[Dogtrousers]

Thread closed until the 'spat' posts are removed.

What, has @Accy cyclist been posting about his footwear on here?

 

[Alex321]

And why has no-one mentioned the wet-weather squealing?? I think that's a great feature!

Doesn't even need wet roads - even a foggy day seems enough!

I think that depends a lot on the setup - and the type of pads. Resin pads are less prone to squealing than sintered or semi-metallic.

 

[Profpointy]

And why has no-one mentioned the wet-weather squealing?? I think that's a great feature!

Doesn't even need wet roads - even a foggy day seems enough!

Just to clarify, is it worse or better with discs? I've never ridden a disc braked bike

 

[Alex321]

Just to clarify, is it worse or better with discs? I've never ridden a disc braked bike

Discs generally sqeual in the wet much more than rim brakes. But they continue working almost as well in the wet, unlike rim brakes

 

[Webbo2]

And why has no-one mentioned the wet-weather squealing?? I think that's a great feature!

Doesn't even need wet roads - even a foggy day seems enough!

You should try rim brakes with carbon rims. It sounds like a jet coming in to land.🤣🤣🤣

 

[Profpointy]

Discs generally sqeual in the wet much more than rim brakes. But they continue working almost as well in the wet, unlike rim brakes

As an aside when discs first became popular on motorcycles, questionable wet weather performance was a big issue with them, particularly with the shiny steel discs on the Jap bikes. Gradually this was resolved with cast iron discs, which rusted so didn't look as nice but did work in the wet, aggressive pads (sintered metal was the term I think) and grooved / drilled discs which helped shed the water

 

[fossyant]

It isn't about a small movement, it is about how much less hand pressure is needed.

It is much easier to vary when you don't need much than it is when you need to use a lot of strength.

Almost everybody I have heard of who has ridden both says it is easier to modulate with disc.

Definately finger/hand pressure. Not always felt much on a road bike but if descending alot with fully loaded panniers it's hard work with rim brakes. Serious hand ache after 4 days of all day riding with a loaded bike and rim brakes. The brakes stop well, but if you are needing to hold the brakes on hard over rough ground then discs win by miles (i.e less hand fatique).

MTB is a different thing as the braking power is immense with decent disc brakes.

 

[Dogtrousers]

I recall a bit of resistance from the pro peloton to the introduction of disc brakes. We were led to believe that they could cause bad wounds in crashes, and get very hot and cause burns.

https://road.cc/content/tech-news/186146-have-disc-brakes-really-led-injuries-peloton
https://www.granfondoguide.com/Contents/Index/2468/pro-peloton-acts-on-disc-brake-safety-fears

This went very quiet very quickly. Possibly when Mr Shimano and friends reminded the riders which side their bread was buttered.

Looks like it has been 10 years. How time flies.

 

[Alex321]

As an aside when discs first became popular on motorcycles, questionable wet weather performance was a big issue with them, particularly with the shiny steel discs on the Jap bikes. Gradually this was resolved with cast iron discs, which rusted so didn't look as nice but did work in the wet, aggressive pads (sintered metal was the term I think) and grooved / drilled discs which helped shed the water

But wasn't that a change from drum brakes to disc brakes, rather than rim to disc?

Disc brakes are more exposed to weather than drum brakes are, but less exposed than rim brakes.

 

[Dogtrousers]

Disc brakes are more exposed to weather than drum brakes are, but less exposed than rim brakes.

on bicycles aren't they more or less equally exposed?.. Discs are closer to the road catching spray. (not claiming any expertise, just wondering)

 

[Alex321]

on bicycles aren't they more or less equally exposed?.. Discs are closer to the road catching spray. (not claiming any expertise, just wondering)

Not really.
Rim brakes catch all the water carried around on the rim from the wet roads, while discs only get rain - any spray from the road will be going backwards much more than upwards.

The rear disc may catch some spray from the front wheel, but the rear is doing much less of the braking normally anyhow.

 

[rydabent]

Everyone can debate disc brakes, but due to economies of scale, they are here to stay. The more disc brakes mfg buy the cheaper they are. Even low cost bikes now have them.

 

[fossyant]

I recall a bit of resistance from the pro peloton to the introduction of disc brakes. We were led to believe that they could cause bad wounds in crashes, and get very hot and cause burns.

https://road.cc/content/tech-news/186146-have-disc-brakes-really-led-injuries-peloton
https://www.granfondoguide.com/Contents/Index/2468/pro-peloton-acts-on-disc-brake-safety-fears

This went very quiet very quickly. Possibly when Mr Shimano and friends reminded the riders which side their bread was buttered.

Looks like it has been 10 years. How time flies.

The road discs are finished differently, ie the main edge is rounded more (someone correct me if not). The MTB ones aren't, certainly not on my SRAM. You also have to move with spare wheel compatability, so everyone needs to move.

Loads of cheap high end rim braked bikes second hand these days.. bonus for us rim brake maffia.

 

[Profpointy]

But wasn't that a change from drum brakes to disc brakes, rather than rim to disc?

Disc brakes are more exposed to weather than drum brakes are, but less exposed than rim brakes.

Yes indeed, I should have made that clear. My post wasn't anti-disc or anything but just an observation that in the motorcycle context discs supposedly had worse wet weather performance than their predecessor (drums), though for pedal cycles they are apprently an improvement over rim brakes in the wet

 

[Ming the Merciless]

Discs are closer to the road catching spray

Only if your rim has collapsed