KCNC C7 brakes and pad suggestions

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milkbaby
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by milkbaby

Hi, my 1 st post...

I just got a bike with KCNC C7 brakes on it and put stock Ultegra 6700 pads in them, but the braking power is awful. Any good suggestion for pads to try in there for aluminum rims or are these brakes just too flexy?

If it matters, I'm running SRAM red levers/shifters. No climbing or descending where I live, but I'd be afraid to run my carbon clinchers with these brakes.

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prendrefeu
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by prendrefeu

Swiss Stop greens and/or how much do you weigh?
C7's can be perfectly good for lighter riders.
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jmartpr
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by jmartpr

+1 on the SwissStop greens....or if you want a bit more agressive bite just use the Yellow SwissStop for carbon, they will wear a bit faster.

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DMF
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by DMF

My new C7's came with green swissstops, haven't tried them yet though as it's winter season. They also came with some no name (I assume cork) pads for carbon rims... I'm running aluminum braking surface, but I've never heard that you could use carbon specific pads, such as yellow swissstops, for improved braking force...

Is this true and would the cork pads supplied by KCNC work better than the green swissstops?

eric
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by eric

Yellow SwissStops work poorly on aluminium rims. Cork pads don't work on aluminium either. You need the appropriate pads for your type of carbon rim- some work well with cork based pads, on others those work poorly and damage the rim. It's best to use what the rim manufacturer recommends- they usually do testing.

I think the best pads for aluminium are the new dura ace 7900 pads. Make sure the rim is clean and the pads are square on the rim. Then set toe in to no more than a business card's worth. I've been using no toe in on 7800 brakes and aluminium rims, but the KCNCs are flexy and might work better with toe-in.

mjduct
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by mjduct

eric wrote: Then set toe in to no more than a business card's worth. I've been using no toe in on 7800 brakes and aluminium rims, but the KCNCs are flexy and might work better with toe-in.



I never understood the purpose of toe in? that little of it would wear itself out in a ride or two. I just square mine up perfectly and then I have consistant braking as they wear, and even wear through the pad.

BTW I'm running C7's with the green swissstops that come with them on Easton EA90 rims... I weight about 165lbs. and don't have monster hills in my area. braking isn't as good at the campy brakes they replaced but they weight a half pound less and work good enough for my purposes when set up properly.

eric
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by eric

Toe in is needed because the calipers twist when the brake is applied. Without toe in, the leading edge of the pad is pulled in and more of the force is on it. This can sometimes cause the pad to vibrate, which you hear as squeal.

If the pads are toed in the ideal amount, when the brake is applied and the caliper twists the pad ends up square to the rim.

If they are toed in too far, then the pads wear at an angle but at least the brakes squeal less.

edmundo
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by edmundo

I use SwissStop greens on alloy rims with KCNC CB1s which are flexier than C7s. I'm 150 pounds (70kg) and they work fine. However, I don't think I'd be happy with this combination if did any serious descending.
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yeagermeister
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by yeagermeister

I am using my C7's with greens also but I switched out the cables first from steel to teflon coated cables while using the stock pads. This made the biggest difference and now they work great.

milkbaby
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by milkbaby

I'm 130-135 pounds right now, and the pads I switched in were the Dura Ace 7900 pads. :( When these wear down, I think I will try the SS green, but I have the feeling these calipers are just too flexy. They definitely felt flimsy when I was setting them up. Thanks for the suggestions! :thumbup:

yeagermeister
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by yeagermeister

I'm around 170-175lbs. They are definitely more flexible than 7900 calipers. I guess it really depends on what you want out of the brakes, the KCNC's are fine for me but if you want pure breaking power its hard to beat Dura-Ace.

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by jmartpr

eric wrote:Yellow SwissStops work poorly on aluminium rims. Cork pads don't work on aluminium either. You need the appropriate pads for your type of carbon rim- some work well with cork based pads, on others those work poorly and damage the rim. It's best to use what the rim manufacturer recommends- they usually do testing.

I think the best pads for aluminium are the new dura ace 7900 pads. Make sure the rim is clean and the pads are square on the rim. Then set toe in to no more than a business card's worth. I've been using no toe in on 7800 brakes and aluminium rims, but the KCNCs are flexy and might work better with toe-in.



Eric.....Yellows do work on Alloy but are not recomended because they are way softer and grab hard the rims with less modulation. I personally used them on some alloy climbing wheels for some extra braking power but this came at the expense of increse wear on the pads. Their compound is based on rubber (not cork or other material) designed to work at higher temps and softer, so they grab better the slippery brake surface of some carbon rims. Zero Gravity shipped their brakes with Yellows as the standard pad. If we were talking about general carbon pads, like the ones shipped with KCNC C7 brakes, then I would agree that they are not good on alloy rims.

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astranoc
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by astranoc

Resurrecting this old thread to ask for advise, I have the c7 with the Reynolds cryo pads and the breaking is at least appalling, it feels extremely spongy and there is not much stopping power. I 've tried them with cork pads too and had the same result. Rims are gigantex and farsports. Could it be the jagwire cables that causing this? Any ideas what to try?

eric
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by eric

Different brakes.

dem
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by dem

I've been (embarrassingly) 200+ pounds with CB1s, and never felt they were dangerous. I used kool-stop salmons and descended plenty of mile plus switchbacky 10-15% grades.

They WERE terrible with American Classic AC420 rims. The braking surface on those rims is extremely narrow and impossible to get good bite on. Using a variety of other rims (Soul, Velocity, Bontrager, etc.) - they were fine.

There's definitely an element of knowing how to descend - brake before you turn, let yourself hit terminal velocity instead of riding your brakes, etc.

Would I ride them in a big pack on the ragged edge? No, but I've never felt unsafe.

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