Disc or rim brakes ?

[T.M.H.N.E.T]

I know there's lots of debate about fork problems with the extra forces that come from disk brakes as well as the problems from heat generation. I'm not sure these are really problems with riders such as us (more an issue for pros).

They're not issues in particular, for anyone

 

[Drago]

Don't think id be fussed either way, so long as they do the job proper like. Ive ridden great rim brakes and crape discs, so their performance is of far more interest to me than any one particular set up.

 

[phantasmagoriana]

Depends on the conditions you ride in. My summer bike's got rim brakes, which work fine, but I've just bought a new winter bike (one of the CX/gravel type bikes) with discs as I hate spending longer cleaning bikes than riding them in the winter!

 

[ianrauk]

Discs all the way.

 

[T.M.H.N.E.T]

....although the CTC magazine had quite a debate about the heat generation caused by disks when descending down alpine passes on stage races. To quote Richard Hallett

'Perhaps surprisingly, riding on the road poses a greater problem for discs than off-road as speeds on descents are potentially so much higher and kinetic energy, which is what brakes must absorb, varies as the square of velocity. Participants in high-speed downhill mountain biking events such as Megavalanche have reported complete loss of power after long, hard braking efforts.

At 60mph, a cyclist has nine times the kinetic energy of a cyclist travelling at 20mph and slowing an 80kg bike and rider from 60mph to 20mph in three seconds generates 8.5kW, which heats the disc – to as much as 500ºC depending on front/rear brake usage.

This is more than enough to cause permanent scarring if a hot disc touches skin. By comparison, an aluminium rim might only reach 90ºC in short bursts of braking. Those who dismiss concerns about burns resulting from bunch crashes in road races have surely not experienced mountain biking’s ‘rotor burn’.'

I'm just putting the argument, although it's not behind my decision. Rim brakes work for me and I'm happy to stick with them.

I've got off my bike after descents and wrapped my hand around the disc, that may well indicate how hot they don't get

 

[Drago]

Yet I've also seen rotor-burn scars with my own eyes.

 

[ianrauk]

What have you got on your bikes Ian?

Discs on my commuter/tourer. Rim on my Van Nic and when I get round to replacing it, it will be a bike with discs.

 

[Drago]

Wrap your hand round this chaps discs...

 

[rideswithmoobs]

Don't think id be fussed either way, so long as they do the job proper like. Ive ridden great rim brakes and crape discs, so their performance is of far more interest to me than any one particular set up.

Agree it's performance but if like me you can only have 1 bike then would it be a disc or a rim. Fir example a CAAD12 105 rim or a CAAD12 disc, both excellent bikes but if you shell out for the rim version are you paying for old outgoing tech or are disc just a new uneccessary? I don't know hence the query. My Genesis is disc but not having a rim to compare I don't know. Prior to that it was a cube cross race canti and they were garbage in the wet

 

[T.M.H.N.E.T]

For a do-it-all bike with proper bolt mounted mudguards and chunky rubber it's almost certainly a KO victory to discs.

 

[Drago]

Agree it's performance but if like me you can only have 1 bike then would it be a disc or a rim. Fir example a CAAD12 105 rim or a CAAD12 disc, both excellent bikes but if you shell out for the rim version are you paying for old outgoing tech or are disc just a new uneccessary? I don't know hence the query. My Genesis is disc but not having a rim to compare I don't know. Prior to that it was a cube cross race canti and they were garbage in the wet

I don't care if its cutting edge or old tech - I care only that it works, because I'm a cyclist not a fashion victim. I want the best brakes for my money and the type of bike, and I don't care if they're rims, drums, discs or an anchor and a rope.

 

[rideswithmoobs]

I don't care if its cutting edge or old tech - I care only that it works, because I'm a cyclist not a fashion victim. I want the best brakes for my money and the type of bike, and I don't care if they're rims, drums, discs or an anchor and a rope.

Maybe your mistaking what I'm saying or asking. Your point about 'fashion victim' is exactly the reason I'm asking the CC forum because it's full of true cyclists and I do not know enough about the disc vs rim and if indeed it's a fashion. I wish to purchase a bike that functions not one that says ' I have all the gear and f-all idea'

 

[Supersuperleeds]

Another disc fan here, though I do love the simplicity of rim brakes.

 

[NorthernDave]

I'm fairly certain that my next road bike will have discs.
But that's just me...

 

[Kajjal]

Either works but discs have more power, better control and are not affected by the wet. Check GCN on YouTube for a proper comparison. If you are lightweight, ride in the dry and on very good roads the difference is less. If heavier, ride in the wet and on rougher looser roads then the difference is very marked. I weight 100kg and have never had problems braking with hydraulic discs even on very long or steep descents in the UK.