Disc brakes

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Hardrider
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Joined: 17 Nov 2017, 4:25pm

Disc brakes

Postby Hardrider » 22 Jan 2018, 2:24pm

I am keen to build a carbon fibre framed bike with disc brakes. I use campagnolo and am used to this. Without spending a fortune, I wondered if I could use my existing group but with mechanical discs. I have heard that these are difficult to set up and tend to rub most of the time. Does anyone have any knowledge of these?

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[XAP]Bob
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Joined: 26 Sep 2008, 4:12pm

Re: Disc brakes

Postby [XAP]Bob » 22 Jan 2018, 4:02pm

If the frame has disc mounts then you'll be fine - get BB7s of the appropriate type (road and MTB have different cable pulls) and you can set them up properly.

Other brake types work as well, but BB7s tend to be highly regarded.
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KM2
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Re: Disc brakes

Postby KM2 » 22 Jan 2018, 4:06pm

Look into trp disc brakes. They move the pads both sides unlike the bb7's.

PeterBL
Posts: 166
Joined: 26 Oct 2010, 1:04pm

Re: Disc brakes

Postby PeterBL » 22 Jan 2018, 4:14pm

I am running Campagnolo Ergopower with Avid BB7 Road. Be careful with the first setup and the performance is fine. There isn't very much adjustment or maintenance to do.

reohn2
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Re: Disc brakes

Postby reohn2 » 22 Jan 2018, 5:04pm

[XAP]Bob wrote:If the frame has disc mounts then you'll be fine - get BB7s of the appropriate type (road and MTB have different cable pulls) and you can set them up properly.

Other brake types work as well, but BB7s tend to be highly regarded.

+1 for BB7's.
Rubbing rotors are because they're out of true.True rotors and properly set up calipers don't rub.
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rmurphy195
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Location: South Birmingham

Re: Disc brakes

Postby rmurphy195 » 22 Jan 2018, 5:21pm

Unless you want to replace the levers, check re compatibility of the brake with your existing levers. Also check how bulky (or otherwise) the brakes look.

Never had a problem with discs rubbing with the TRP Spyres on my Condor, nor any other problems once set up properly.

Significance of twin pistons - the two pistons move together to clamp the disc, whereas single pistons move one pad and then bend the disc to push it against the other. For the latter, the longer you leave the adjustment the more the disc bends. If the disc bends then it probably wears the pads at an angle - how acute this would be though I have no idea.
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reohn2
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Joined: 26 Jun 2009, 8:21pm

Re: Disc brakes

Postby reohn2 » 22 Jan 2018, 5:59pm

rmurphy195 wrote:Unless you want to replace the levers, check re compatibility of the brake with your existing levers. Also check how bulky (or otherwise) the brakes look.

Never had a problem with discs rubbing with the TRP Spyres on my Condor, nor any other problems once set up properly.

Significance of twin pistons - the two pistons move together to clamp the disc, whereas single pistons move one pad and then bend the disc to push it against the other. For the latter, the longer you leave the adjustment the more the disc bends. If the disc bends then it probably wears the pads at an angle - how acute this would be though I have no idea.

Not appreciably IME.
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Brucey
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Re: Disc brakes

Postby Brucey » 22 Jan 2018, 6:21pm

yup, it doesn't make any real difference to, well, anything really.

For me there is one plus point about the spyre; that is the caliper is better tucked in at the rear and this can make fitting a rack easier etc. There are some downsides; the latest version has a grub screw to secure the cable (bad idea), pad adjusters that don't stay adjusted (the last set of spyres that I looked at were 'bending the disc' worse than a set of badly adjusted BB7s... :roll: ), and have a bunch to tiny (~1.5mm dia), inadequately protected ball bearings in each side of the caliper.

The last of these means that after a year or so these calipers usually no longer feel smooth in operation; the reason is that the bearings have been damaged and there is no repair possible. If you fancy preventative maintenance, it takes a very long time to strip and regrease these calipers.

cheers
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Si
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Joined: 5 Jan 2007, 7:37pm

Re: Disc brakes

Postby Si » 22 Jan 2018, 8:35pm

I have bb7, and if i can set it up easily and without swearing then just about anyone can

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foxyrider
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Location: Sheffield, South Yorkshire

Re: Disc brakes

Postby foxyrider » 22 Jan 2018, 9:24pm

Just buy the Potenza brakes?

I've been running TRP HY/RD's off of Chorus 11s carbon levers for @ 3 years. They work okay but I hate the lack of feedback from discs so i'm maybe not the best person to advise on performance.

However the new Campag brakes, designed in conjunction with Magura ( who have a finger in the SRAM and Rotor brakes too) have had some excellent reviews.
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Hardrider
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Joined: 17 Nov 2017, 4:25pm

Re: Disc brakes

Postby Hardrider » 23 Jan 2018, 12:17pm

Buying Potenza brakes sounds good but for me that would mean the whole groupset. I have 9 speed Record and 9 speed Chorus to add brakes to. Thanks to all for the advice. I shall look for a suitable frame in the sales

rmurphy195
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Location: South Birmingham

Re: Disc brakes

Postby rmurphy195 » 23 Jan 2018, 8:54pm

Furtheer to Bruceys comment - I have a normal rear rack(rescued from a 25 year old Galaxy) on my Spyre equipped Condor (where the caliper sits in the angle between the seatstay and chainstay), fitted no problems. At the front, the stays needed bending to get around the caliper.
Brompton, Condor Heritage, creaky joints and thinning white (formerly grey) hair
""You know you're getting old when it's easier to ride a bike than to get on and off it" - quote from observant jogger !