Campagnolo classic sidepull brakes … today

[Vetus Ossa]

I have just sold a bike with Campag piccolo brakes with the shoes half way up the slot.
All of the cables were good, and the brake block were newish, but quite honestly they were pretty poor in operation.
They may have been state of the art in their day, but apart from looking beautiful I wouldn’t choose them for stopping power.

When I first built my Mercian in 1986, I fitted Campag Victory Piccolo brakes complete with matching levers.
They were excellent. No issues whatsoever. Great stopping power. I used them with Mavic MA40 rims.
I sold the brake set in 2004 when I modernised the whole group-set.

The Mercian now has Campag Athena D brakes - dual pivot at the front, and single pivot at the rear - operated by Campag Chorus Ergo levers. I can't say they are any better than the old Victory brakes.

Strange isn’t it. I have owned several classic bikes with campag brakes and levers and never thought them up to much.
My favourite, though retro now are shimano rx100, I like them aesthetically and stopping power. The levers I also like.

[Mick F]

This is the bike in 1994 at Helmsdale at the end of the first day of JOGLE.
Victory brakes and blocks, and Victory levers, but I used white Aztec stainless/teflon cables. Original cables were grey.

[speedsixdave]

If you fancy the Campag single-pivot look but not the price, Shimano 600ex brakes (just pre-Ultegra) look good and work well. £35 on eBay here. Or the posher Dura-Ace of similar and slightly later vintage. 600ex come in 'deep' drop (47-57mm) too, which may or may not be a bonus.

If you need shallow drop only, there are lots of grades and vintages of lovely Modolo single-pivots too. No idea how well they work but they look classy.

[Samuel D]

Some of those Shimanos look pretty decent, speedsixdave. And notably cheaper than Campagnolo. I’d need the 47–57 mm reach.

Could the state of lubrication of the pivot account for some of the differences in perception of the power of these brakes?

Mick F’s “Aztec stainless/teflon cables” may have helped in his case. And I gather he has a strong grip too.

I can’t get a straight story out of anyone on whether there’s something about these brakes that prevents them braking harder as lever force increases. The pivot is far from the pads, so the reaction load there would be high. There are some clever design features in the pivot to accommodate this as explained here.

On another note, does anyone know if classic Campagnolo sidepulls can be converted from recessed to external-nut? From pictures, it seems to be only a matter of finding the right bolt and nuts – although that in itself may be tricky these days, of course.

There is a surprising number of recessed versions on eBay and the like, but I’m tempted to go with external-nut fittings if I ever order a custom frame in the future, the better to add and remove mudguards. My present Spa Audax has recessed holes.

[Brucey]

the reaction load at the pivot does not depend solely on the distance of the pivot from the brake blocks. You can have this distance large and the reaction load be small, in fact.

So far as brake power goes there are several issues

1) system MA
2) cable tension (higher = more friction, generally)
3) pivot friction
4) brake block squashiness
5) brake block friction coefficient
6) brake arm flex

Some of these factors interact with one another in unexpected ways.

Campag brake bolts are (were) expensive back in the day. Although they crop up on ebay from time to time, I recommend buying nutted calipers from the start if you can (and in fact the longer reach ones were more likely to be like this from the start). If you buy AK fitting brakes you will usually need one (front) longer nutted bolt; the old front is usually the correct length for the rear brake.

cheers

[Gattonero]

Still looking for greater simplicity of conception and maintenance with sufficient performance in my bicycle, I’ve wondered if the classic sidepull calliper brake might suit me. That is, single pivot instead of dual pivot, preferably with brake cables arching over the handlebar instead of aero routing.

I roughly measured the mechanical advantage of my present Shimano BR-R650 and BL-R400 set-up at 6:1. Traditional single-pivot callipers and levers come to about 4:1, so, prima facie, I’d be giving up about a third of the retardation for a given lever force. Since my current brakes are powerful verging on excessive in emergency stops, that would not present obvious problems.

Do you still have single-pivot brakes with externally routed cables on a frequently used bicycle? If so, is that for functional reasons?

I like the look of old Campagnolo Super/C-/Nuovo/plain Record brakes and levers. However, they’re expensive and various. Any tips for finding a good set at a reasonable price? I’m hoping to find something in NOS or mint condition to avoid inheriting the product of someone’s bad mechanicking.

I could con myself into thinking a high price was justified for something that would last a long time, but my BR-R650s are showing light corrosion on only their third winter. Maybe nothing lasts for long if used throughout the year.

Encouragement or cautionary tales are welcome.

I have used "monoplanar" brakes on two bikes, and eventually ditched them because they get very noisy on polished rims (it was much easier to replace the brakes than the rims), otherwise they were good enough.
Personally, I cannot see any trouble in a dual-pivot design, indeed they're arguably easier to balance left/right as you can move the whole caliper (the fine-tune with the screw), while the SP design you will have to operate on one or more bolts and sometimes with special tools.
One more pivot can seize just as a single pivot, but even before going there I'd choose full mudguards to reduce the road-spray on the brake calipers.

I have used some Dia-Compe BRS on a road bike a while ago, braking power was ok but not fantastic when going over 60kmh. They were short drop, but there may be ones with longer drop.

[Samuel D]

I have used "monoplanar" brakes on two bikes, and eventually ditched them because they get very noisy on polished rims (it was much easier to replace the brakes than the rims), otherwise they were good enough.

By noisy you refer to squealing? Polished rims don’t have polished brake tracks (or if they do, not for long), so I’m curious what you mean.

Dual-pivot brakes are indeed easy to centre, but several things about their design bother me slightly:

• the pad on the short arm with the offset pivot moves up toward the tyre as it wears. I ride a fair bit in all weather and that means I spend longer than I like fiddling with pad position, checking it frequently, and otherwise spending thought on this problem. It is aggravated by my rims that have short brake tracks
• to minimise the consequences of the problem above, the pads don’t have much wear material – not even 5 mm in some cases – and therefore don’t last long in the wet
• one pad always wears a little faster than the other. I think this is because the arms move at different rates as the cable is pulled, i.e. you’d need to constantly re-centre the brake as the pads wear and anyway the centring would only be valid for one braking force (that is, for one calliper position). The brake’s practical functioning relies on the rim flexing laterally
• the brakes can feel grabby at times, in particular when trimming speed with gentle braking in fast corners in the wet. This may be related to my wheels not being perfectly true (but hardly any bicycle wheel is, nor should it have to be). Shimano’s SLR design of having a return spring in both the calliper and the lever makes it worse while conferring other benefits. My acute awareness of the danger of braking in wet corners, where there’s not much spare traction budget, adds to my distress here. This off-camber, downhill corner at Longchamp comes to mind (not my video)
• related to the above, if the wheel is severely out of true – for example because a spoke breaks – the brake cannot follow the rim. Any rim wobble is made worse by pad clearance at the low end of useable in my set-up with ~6:1 mechanical advantage.

I don’t doubt single-pivot brakes have their own problems, but maybe I would prefer them to all of the above. As with so many things, reading hasn’t told me. I’d need to try them for myself.

[Brucey]

There is a reason the monoplanar brake design has not been copied by other brake makers... they are great until they get even slightly worn; then they become a PITA; the slack cannot be adjusted out in the same way as with every other side-pull brake, not without crushing the slotted arm (and NB any preload on it in service makes it draggy.... ). The adjustment can only sensibly be made with shim washers, which have to be made specially. Fitting them is very tedious work too.

If you leave free play in the arms, monoplanar brakes can be pretty horrible to use and may indeed be noisy etc.

You need not concern yourself with this brake design anyway; IIRC it was only available in short reach form and isn't usually seen with mudguards of any sort beneath.

cheers

[Samuel D]

Ah. And such play might cause squealing.

I don’t see an obvious advantage to the Monoplanar design. Something else for me to read about…

More tempting by far is a pair of Super Record brakes being sold locally at a price low enough that I could guarantee a profit if I didn’t like them and resold them. They’re not NOS but they seem to be in top condition, albeit with recessed Allen-key fittings. They could be mislabelled Nuovo Record callipers; I can’t tell and don’t think I mind one way or the other.

[Gattonero]

I have used "monoplanar" brakes on two bikes, and eventually ditched them because they get very noisy on polished rims (it was much easier to replace the brakes than the rims), otherwise they were good enough.

By noisy you refer to squealing? Polished rims don’t have polished brake tracks (or if they do, not for long), so I’m curious what you mean.

Dual-pivot brakes are indeed easy to centre, but several things about their design bother me slightly:

• the pad on the short arm with the offset pivot moves up toward the tyre as it wears. I ride a fair bit in all weather and that means I spend longer than I like fiddling with pad position, checking it frequently, and otherwise spending thought on this problem. It is aggravated by my rims that have short brake tracks
• to minimise the consequences of the problem above, the pads don’t have much wear material – not even 5 mm in some cases – and therefore don’t last long in the wet
• one pad always wears a little faster than the other. I think this is because the arms move at different rates as the cable is pulled, i.e. you’d need to constantly re-centre the brake as the pads wear and anyway the centring would only be valid for one braking force (that is, for one calliper position). The brake’s practical functioning relies on the rim flexing laterally
• the brakes can feel grabby at times, in particular when trimming speed with gentle braking in fast corners in the wet. This may be related to my wheels not being perfectly true (but hardly any bicycle wheel is, nor should it have to be). Shimano’s SLR design of having a return spring in both the calliper and the lever makes it worse while conferring other benefits. My acute awareness of the danger of braking in wet corners, where there’s not much spare traction budget, adds to my distress here. This off-camber, downhill corner at Longchamp comes to mind (not my video)
• related to the above, if the wheel is severely out of true – for example because a spoke breaks – the brake cannot follow the rim. Any rim wobble is made worse by pad clearance at the low end of useable in my set-up with ~6:1 mechanical advantage.

I don’t doubt single-pivot brakes have their own problems, but maybe I would prefer them to all of the above. As with so many things, reading hasn’t told me. I’d need to try them for myself.

My Monoplanar brakes were always kept in good condition, can't see myself wearing them that much to get play, and even so you can tweak with shims.
The problem I had with them, was a lot of noise when braking, especially on cold days. This was due to the polished rims and brake pad compound. Using some old Record Ti (non-Skeleton) with standard RE700 brake pads cured the problem easily. Btw, though the pull-ratio is not ideal those brake do still work very well with C-Record levers.

1&3: I'd like to know what brakes are you using, as this sounds an exacerbation of a problem that doesn't really show up
2: 5mm of braking compound will do many miles, if you experience a lot of wear I'd advise for frequent cleaning of the pads and rims (which should be always done nevertheless) especially to save the rims. In fact, I replace the pads always before they wear out completely, ought to be the reason why I get many tens of thousands miles in all weather from standard OpenPro's that some people can wear out in less than a year of commuting
3: it sounds to me like you're using a brake with a top-side centering grub screw, and this is not set properly. If correctly done, the brake will not move away from it's centered position, nor it will rely on the rim flexing on one side (!)
4: assuming that you have the correct caliper for a given lever, the "grabby" feeling is related to pads&rim materials, modern brake pad compounds of good quality don't make noise nor will be grabby. I've used Campagnolo (for decades) and Swissstop (for many years now) and never experienced any "grabby" feeling even when going down the Dolomites at 80kmh.
It's not strange then, on Corima carbon rims I do get a very bad modulation when not using the recommended brake pads
5: if the bike has std. caliper brakes, I'd assume the frame&forks won't have tons of clearance on the sides, so it needs more than one broken spoke to send a standard 32 or 36 spoke wheel that much out of true that a DP caliper won't cope. You're likely to have the tyree rubbing on the frame/forks well before that.

I understand you prefer SP calipers, it's fair enough. But give a try to a pair of Campag DP brakes (not the latest ones) and you'll be surprised that you won't get any of the problems you fear

[Brucey]

IIRC Samuel is using BR-R650 calipers that reach far enough to allow ~28mm tyres and mudguards to be fitted with a good clearance. No Campag brake (that is younger than ~35 years.... ) will fit; they are all too short. In addition the rims (Exal LX17?) have a very narrow brake track.

I see a lot of rims worn badly by DP brakes where the brake block attached to the centre-pivoted arm has gone below the brake track and similarly the other brake block (on the offset arm) has started to go into the tyre. I'd suggest that thinner brake block inserts (that are changed more often) as used in XTR pattern MTB holders, for example, might be a better idea when using rims that have narrow brake tracks.

BTW there is a small but potentially significant variation in the geometry of DP brakes; in some models the separation of the two pivots is smaller than others, and this allows the offset arm to have a more favourable movement arc than if the separation were larger (cf. canti boss spacing variations). Unfortunately this also increases the load in the DP arm-to-arm coupling, and pretty much any DP brake that is meant to clear mudguards has a large-ish pivot separation, so that the mudguard will fit underneath OK.

cheers

[Samuel D]

1&3: I'd like to know what brakes are you using, as this sounds an exacerbation of a problem that doesn't really show up

It shows up alright. Here’s a bad video I just took with my phone that shows my rear brake from the front. The pad that was well positioned a few wet rides ago – I checked it then while working on the front pads – has crept above the brake track, creating a lip that will soon tickle the tyre. It needs immediate adjustment (and needed it days ago).

How is this not a practical problem?

The brakes are Shimano BR-R650, but all similar designs suffer from the problem. The rims are Exal XR2 with an 8 mm brake track. Even if another rim would fix this, I see the problem to be with the brakes rather than the rim. But what rim do you suggest?

2: 5mm of braking compound will do many miles, if you experience a lot of wear I'd advise for frequent cleaning of the pads and rims (which should be always done nevertheless) especially to save the rims. In fact, I replace the pads always before they wear out completely, ought to be the reason why I get many tens of thousands miles in all weather from standard OpenPro's that some people can wear out in less than a year of commuting

If you brake hard in the wet as I often do, the pads wear quickly. Rolling up to a traffic light on a commute is another matter; I think my pads would last a year or two doing that, even in the wet.

Replacing brake pads before their short life is over is not an attractive solution.

3: it sounds to me like you're using a brake with a top-side centering grub screw, and this is not set properly. If correctly done, the brake will not move away from it's centered position, nor it will rely on the rim flexing on one side (!)

They’re perfectly set up per Shimano’s instructions. The rim is required to flex because the dual-pivot brake has different arm-closure rates and cannot be pushed off-centre. Flexing the rim is also how slight rim wobbles are dealt with by this type of brake. The rim readily flexes but not before causing asymmetric pad wear from light braking.

As for the grabby action, it doesn’t show up in hard braking. It becomes dangerous when feathering the brake while cornering near the traction limit. To use the vernacular, the modulation could be better.

I see a lot of rims worn badly by DP brakes where the brake block attached to the centre-pivoted arm has gone below the brake track […]

In those cases, I think they must have been set up incorrectly to begin with (a very common thing in my experience). That pad doesn’t move much with wear.

[Gattonero]

1&3: I'd like to know what brakes are you using, as this sounds an exacerbation of a problem that doesn't really show up

It shows up alright. Here’s a bad video I just took with my phone that shows my rear brake from the front. The pad that was well positioned a few wet rides ago – I checked it then while working on the front pads – has crept above the brake track, creating a lip that will soon tickle the tyre. It needs immediate adjustment (and needed it days ago).

How is this not a practical problem?

The brakes are Shimano BR-R650, but all similar designs suffer from the problem. The rims are Exal XR2 with an 8 mm brake track. Even if another rim would fix this, I see the problem to be with the brakes rather than the rim. But what rim do you suggest?

What I see is a brake pad that's not correctly positioned to begin with.
Pretty much ALL the brakes work by moving on an arc, so you WILL have this problem nevertheless. Some cantilevers brakes are particularly bad in this as they move on a short radius.
An rims with a silly narrow braking track don't help. But when correctly setup, normal DP brakes like Campag or even Shimano ones, do not give this problem. I've setup tens of thousands of brakes on similar narrow rims like OpenPro's or Excellence and never seen this problem to be significant as in the video.

2: 5mm of braking compound will do many miles, if you experience a lot of wear I'd advise for frequent cleaning of the pads and rims (which should be always done nevertheless) especially to save the rims. In fact, I replace the pads always before they wear out completely, ought to be the reason why I get many tens of thousands miles in all weather from standard OpenPro's that some people can wear out in less than a year of commuting

If you brake hard in the wet as I often do, the pads wear quickly. Rolling up to a traffic light on a commute is another matter; I think my pads would last a year or two doing that, even in the wet.

Do you have an idea how many times you will have to use brakes while crossing almost half of London? You'd be lucky to ride a 1/4 mile before having to go to a stop. Commuting gives a lot of wear to brakes and other parts of the bike

Replacing brake pads before their short life is over is not an attractive solution.

But it saves you rims, do the maths and see that for the Average Joe brake pads are far cheaper than replacing rims, everyone can rpelace brake pads but not everyone can rebuild his own wheels

The rim is required to flex because the dual-pivot brake has different arm-closure rates and cannot be pushed off-centre. Flexing the rim is also how slight rim wobbles are dealt with by this type of brake. The rim readily flexes but not before causing asymmetric pad wear from light braking.

Nope, the rims are not required to flex, even if we're talking of a tenth of mm it will be negligible while the wheel is spinning. Besides, if we are to be so precise about it, SP brakes won't touch the rims at the same time either

As for the grabby action, it doesn’t show up in hard braking. It becomes dangerous when feathering the brake while cornering near the traction limit. To use the vernacular, the modulation could be better.

When you're going down a 2000mt mountain with long descents, you don't want to arrive at the point where you have to brake hard, most often you slow down more or less quick. Having tried in those conditions both Campagnolo SP and DP brakes, their difference is by far overshadowed by a wrong choice of pads for a given rim. No surprise, standard RE700 pads will never give a "grabby" feeling when mated to a decent rim (OpenPro, DP18, Excellence...) and pretty standard Record DP on 10&11sp Record Ergopowers

[Brucey]

...The rim is required to flex because the dual-pivot brake has different arm-closure rates and cannot be pushed off-centre. Flexing the rim is also how slight rim wobbles are dealt with by this type of brake. The rim readily flexes but not before causing asymmetric pad wear from light braking.

Nope, the rims are not required to flex, even if we're talking of a tenth of mm it will be negligible while the wheel is spinning. Besides, if we are to be so precise about it, SP brakes won't touch the rims at the same time either....

I agree with Samuel. It is obvious that with a DP caliper the brake blocks are moving at different rates (or at best can only move at the same rate when the brake blocks are at one specific height in the slots); if you wear 1mm from the brake blocks, the DP caliper has not been recentred and is rigidly secured to the bike, it isn't unusual to find that the rim is pushed about 0.5mm to one side when the brake is applied. It of course doesn't make any difference if the wheel is turning or not.

It really doesn't matter if an SP brake is a bit lopsided; the arms are not tied together using a linkage, so the caliper is able to move sideways (instead of the rim) as necessary.

Many DP brakes are spared running lopsided as they wear by virtue of the fact that the centrebolt isn't really fully tight; the brake moves around the centrebolt as the brake blocks wear. It isn't at all unusual to have to reposition the brake blocks as they wear; all this talk of it being 'entirely avoidable with a better setup' is in this case mistaken.

cheers

[Gattonero]

In practice, all this talk of 0.5mm (!) doesn't make any difference.
Just try