@tommasini
I'm not convinced that I need to upgrade the rear brake (it is single pivot). Since, under heavy braking, the rear wheel lifts off the ground. You can have the best rear brake in the world then and it won't help!

I am coming to the conclusion that the real problem is the softness (or squashiness) of the pads. With platinum (carbon specific) pads, I can pull the brake lever all the way to the bars. With the ordinary campy pads I can only get the lever half way.

What kind of brake cables are you using?Or there might be some slack on the cables?

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Parlee TT

What are you using for cables and housing and pads? Something like I-Links that are do not compress help quite a bit. For alloy rims I find SwissStop green to be the best gripping pad out there.

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It's all Campagnolo. I'll look into replacing the cables, but I think it's the pad / rim. On alloy wheels with normal pads I get good, solid braking. If I put 404s in with platinum pads it's spongy. (I think that spelling's right!). It's either due to the pad being soft or the rim deforming.

Going back to square one - what is meant by a "platimum" pad. Is that another name for the Campy carbon specific pads? For a time I had used the standard Campy pads intended for aluminum rims and then switched to the cabon specific from campy - the carbon ones felt more solid/less mush versus the standard pads.

tommasini, Zipp has a type of pad for carbon rims they call "plantinum". I think it's their top-end non-cork pad.

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I have DA 7900 levers not Campy but I think the following still applies. I've seen a number of people ask about the "most powerful brakes" available, but I think riders should be looking for the best "modulating brakes" available.

I've tried three sets of calipers all with the same pads (Enve) on with the same levers and same rims (Enve 45). First DA, good and powerful but I found them either ON or OFF. Not much modulation. TRP's I didn't find have much modulation or stopping power. The eebrakes had both stopping power and great modulation. I've heard the eebrake works well with the campy levers.

wassertreter is correct. The reason for my original post is that by moving from alloy rims and normal campy pads to zipp 404s and platinum pads, I am having trouble getting adequate braking during emergency stops (which happen all too often around here). With the 404 and platinum pad, even with no slack in the brakes (virtually no gap between pad and rim) I can pull the brake lever all the way through to the bars and not do a stoppie.

I now believe that this is due to the spongy pads or the rim being deformed. Therefore I reckon that I'm not going to get any more braking performance unless I get disk brakes - and that's a whole other can of worms!

Thanks everyone for your help.

Most powerful road brake? Not that I have tested it, but theoretically wouldn't be the new Magura RT8?

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Your wider zipp rim is taking your callipers outside of their optimum mechanical advantage and reducing the brake mechanical advantage and hence perceived force.
Use shaved or half worn pads on your zipps to improve the feel.

This is why your narrower stnd rim feels superior. Pad hardness will cause bugger all compression at the pad so your chasing a duck there, it will alter feel and hence perceived modulation and depending the compound variance also the braking friction mu of the pad....


Anyhow get your callipers back in range with thinner pads and confirm..

I rate my 7800 DA levers and calipers.

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The newer wider zipp rims are outside the brake specifications of shimano and campagnolo.
Hence brake performance will be suboptimal, even if you optimize pads and cables.

Solutions are either a redesign of the brakes by the major manufacturers or pick some rims that fit specifications (imho there are better options than zipps anyway).