Disc brakes on road bikes

[liambauckham]

i'd love disc brakes on a roadbike! the only downside when moving from MTB to road was the lack of braking

 

[GrumpyGregry]

i'd love disc brakes on a roadbike! the only downside when moving from MTB to road was the lack of braking

I can lock both wheels on my road bike with caliper brakes. How much more braking do I need?

 

[Profpointy]

I can lock both wheels on my road bike with caliper brakes. How much more braking do I need?

Whilst I do rather agree with that, but aren't discs meant to work a lot better in the wet?

On the back it seems a pointless complexity and extra weight, but maybe the front?

That said, motorcyle discs used to be much maligned for wet weather performance as, being out in the rain, they're affected much more than relatively enclosed car disc brakes.

I've got a few years of work to spec up my dream bike, and (front) discs is a key question. So far my only decisions are brooks team pro, pretty lugs (but which tubing?), triple clanger (or maybe a Rolhof)....I guess it'll be a while

 

[GrumpyGregry]

Whilst I do rather agree with that, but aren't discs meant to work a lot better in the wet?

On the back it seems a pointless complexity and extra weight, but maybe the front?

That said, motorcyle discs used to be much maligned for wet weather performance as, being out in the rain, they're affected much more than relatively enclosed car disc brakes.

I've got a few years of work to spec up my dream bike, and (front) discs is a key question. So far my only decisions are brooks team pro, pretty lugs (but which tubing?), triple clanger (or maybe a Rolhof)....I guess it'll be a while

Better modulation in all conditions, more predictable response in the wet, especially if rims are wet and dirty, no rims wearing out, no tubes going pop when rims overheat, ease of maintenance on the road, are the key factors that make me prefer discs.

EDIT: Japanese motorbikes used to have stainless steel discs iirc. Not the best braking surface in the world. Steel Brembos work fine in the wet but do go rusty, until you apply the brakes.

 

[Pale Rider]

Better modulation in all conditions, more predictable response in the wet, especially if rims are wet and dirty, no rims wearing out, no tubes going pop when rims overheat, ease of maintenance on the road, are the key factors that make me prefer discs.

Agreed, to which I would add no worries with brake rub if the wheel is slightly out of true

Scraping the barrel a bit, cleaner rims is a minor advantage, and wheel removal is a bit simpler - depending on how much unhooking the rim brake needs.

 

[GrumpyGregry]

Agreed, to which I would add no worries with brake rub if the wheel is slightly out of true

Scraping the barrel a bit, cleaner rims is a minor advantage, and wheel removal is a bit simpler - depending on how much unhooking the rim brake needs.

Actually, good point. That has got me home, or at least back to transport or civilisation, on more than one occasion with a taco-ed wheel...

 

[Profpointy]

not quite sure I can imagine what "better modulation" means in practice as I've always found harder pull means more stopyness, so I guess I'd have to try for myself. Rim wear - mine have done maybe 12000 commuting miles and seem fine. Warped wheel - true, but if discs rub aren't you totally stuk or can you slacken em off enough? I was put off by descriptions on here of tricky adjusting esepcially as I gather the dis bends to meet the other pad - which sounds like a horrible design - but again, if it works.

Never had 'em though, but would like a go in the wet

 

[GrumpyGregry]

Modulation is all about the range of on-ability of the brake in a range from braking a teeny bit to locking the wheel.

rim wear... I've had mtb rims with V brakes go in three winters; heck of a lot less than 12000 miles.

If the disc gets bent and rubs you bend it back. It may distort if it overheats; folk used to rim brakes often don't understand the braking method with discs on long downhills is different. With rim brakes rider tend to drag the brake for long distances. With disks you freewheel and then brake hard, freewheel and then brake hard as dragging them makes the pads fade and the disks overheat. (but only on really long descents)

cable brakes can be tricky to adjust especially entry level ones. Avid BB5's are parp for adjusting BB7's a cinch. Hydraulic ones are self adjusting.

iirc the cable operated stainless steel front disc on my old Honda CB200 from the early 80's had a bendy disc or some such.

Not my actual bike, and this is a US one with ape hangers...

Works fine on my cable discs (all BB7's)

 

[Pale Rider]

I reckon the cable discs on which only one piston moves is a poor design.

There are now more two piston actuated cable discs, but hydraulic actuation is best of all.

Cheap and simple on a flat bar bike, more complicated with a drop bar.

 

[liambauckham]

I can lock both wheels on my road bike with caliper brakes. How much more braking do I need?

all i know is on my mtb i can stop in near verticle conditions. on the roadbike its a case of squeeze and pray. I know there are other factors like speed and tyres at play here but some of the routes i do go through the bristol to bath railway path which can be a nightmare with pedestrians so often or not you have to make quick adjustments.

 

[GrumpyGregry]

all i know is on my mtb i can stop in near verticle conditions. on the roadbike its a case of squeeze and pray. I know there are other factors like speed and tyres at play here but some of the routes i do go through the bristol to bath railway path which can be a nightmare with pedestrians so often or not you have to make quick adjustments.

that's a whole can of worms right there...

 

[liambauckham]

that's a whole can of worms right there...

sometimes you just have to get your head down, speed up and scream KPLAAAAAAAAAH

 

[LetMeEatCake]

bristol to bath railway path

We did that once at about 4pm. Coming from up here, where on a good day I'll maybe see another 20 cyclists tops (saw 2 today), it blew my mind - we were in a proper cycling traffic jam at one point! Amazing!

Back to the original question - I can see why you might not want them on your shiny, good weather bike, the one that you stroke and care for and clean to perfection with dental floss after every ride. But I don't have one of them. So for me they're worth it for joy of braking throughout winter without having to listen to my rims being ground away to nothing.

 

[liambauckham]

We did that once at about 4pm. Coming from up here, where on a good day I'll maybe see another 20 cyclists tops (saw 2 today), it blew my mind - we were in a proper cycling traffic jam at one point! Amazing!

Back to the original question - I can see why you might not want them on your shiny, good weather bike, the one that you stroke and care for and clean to perfection with dental floss after every ride. But I don't have one of them. So for me they're worth it for joy of braking throughout winter without having to listen to my rims being ground away to nothing.

yeah now the weather is turning the railway path will be mostly full of cyclists rather than sunday family outings. One day I went for a ride and got stuck in amongst a school cycling field trip..... it was like the asteroid scene from empire strikes back.

 

[Andrew_P]

For me nothing to do with modulation, it is having brakes there and ready when it is pishing down and I am flying down a hill having forgotten that I have not applied my brakes for 10 minutes and some plonker pulls out not realising I have to get rid of the water on the rim, and in the split seconds this takes I am starting to panic and do the classic thing of tugging on harder on the feckers and then I lock up and pray that I hold on to it. Then there is the grime from the brake pads on a rim, me and the bike, the cost of the rims getting buggered and replacing my rear pads weekly and lastly usually they free up space for mudguards. So basically I like disc brakes for winter riding.