Do you have disk brakes on your bike?

[mrjemm]

Didn't know those, but my god, they are freaky things. But then TT riders are a freaky mis-shapen bunch...

Doubt those could work with drop bars. I meant the HS77-



(Image copied from Velosniper blogspot).

[Ayesha]

Have a look at the Spesh Secteur.

[reohn2]

Am I right in thinking you can run the longer throw black mtn BB7 version with normal levers, if you use problem solvers' 'travel agents'?

http://problemsolversbike.com/products/travel_agents/

http://www.wiggle.co.uk/problem-solvers-travel-agent/

Or similar, which I'll assume are out there. Though Problem Solvers' has to be one of my favourite websites. The geek in me...

I have T/A's working with V's to STI's on the Santana tandem,they're very good providing good braking.They'd have to be fitted where the cable exits the STI to fit without any jiggery pokery as fitting at the caliper end would need to be "imaginative"
If not using STI's Tektro's RL530 is the answer for MTN black calipers.

There is a shiny new SL (Superlight?) version of the road BB7 though, with black adjusters

I haven't seen those,yet
,

which look quite nifty, though I still prefer my black bodies- if I could find some black adjusters for my black bodies I'd be a happy bunny.

Some folk are sooooo pernickety

Maybe if you want to use STIs and you're really clever you could mangle together some Magura HS77 (hen's teeth hydraulic road rim brakes) levers with hydraulic disc calipers. Or splash big bucks on new SRAM red hydraulics- http://www.bikeradar.com/road/news/arti ... ook-35887/ Sooo ugly though. Or get a cable to hydraulic converter such as Hope's, USE's or TRP's.

As to the original Q, yes, I have BB7 Mtn cable discs on the Vaya, SLX hydraulics on the Malt 2 and a 2nd set of BB7 Mtn on way for the P7 because I far prefer them.

Or maybe buy BB7 road calipers and spray them black if it strums yer strings

[mrjemm]

Shiny things...



Call me daft, but last night when I was unable to get to sleep I was pondering painting some grey shifters black. I won't end up doing it though. Reminds me of one guy who I got on the phone at Spa a couple of times who'd go on about how he'd ride with random colour bits on his bike when I asked after certain colour of parts (i.e. Ortliebs), which always amused me how proud he sounded to not care about such things. I think it was the same guy who'd told Madame she'd be best not to go for one type of tyre because she'd get bored of getting no punctures with them (though she got 2 in short shrift...).

[reohn2]

Shiny things...

Nice!

Call me daft,

Yer daft!

Reminds me of one guy who I got on the phone at Spa a couple of times who'd go on about how he'd ride with random colour bits on his bike when I asked after certain colour of parts (i.e. Ortliebs), which always amused me how proud he sounded to not care about such things. I think it was the same guy who'd told Madame she'd be best not to go for one type of tyre because she'd get bored of getting no punctures with them (though she got 2 in short shrift...).

I try not to let shop assistants influence my madness

[al_yrpal]

I wonder if disc brakes are the future.

Who invented brakes?
What brakes were first on bikes?
How have bike brakes evolved?

Perhaps disc brakes are the best system so far.

How about this Mick. http://autoville.blogspot.co.uk/2011/06 ... stems.html I particularly like the chariot brake with the guy holding the chain. It his wheels aren't connected he would end up going round in a circle. An idea for your trailer?

My first bike had a series of rods as I remember it. It had 24" wheels too. Rottern performance. Then we got cable and now discs.

Personally I prefer discs to anything. I wouldn't consider buying any new bike without them. Absolutely reliable, powerful and dead easy to maintain. Rim brakes are perhaps cheaper which is why so many bikes are still fitted with them.

Al

[Brucey]

I think that disc brakes have their place and their uses, but it isn't on a lightweight roadbike, not yet. Maybe never, in fact.

I daresay that we'll see a lot of roadbikes on sale with discs in the coming few years, and who knows, maybe some pros will even be coerced to ride them, despite the weight and the poor aerodynamics.

But that won't make them the best tool for that job, even. Leave alone for a club racer, where they won't necessarily be any more appropriate than (say) tubs or EPS/Di2 are.

It may not stop them selling though; plenty of riders come to the road after MTBing and quite like discs.

I think that the bike industry's focus on this 'development' is actually a strong sign that they have, collectively, run out of better things they can think of doing at present.

I can think of dozens of things that would actually greatly improve bicycles, and therefore benefit cyclists of many kinds. 'Discs for road bikes' wouldn't even make it into my top twenty.

-just my two pence worth-

cheers

[531colin]

............I can see one disadvantage of disk brakes (particularly if you have a large gear cassette, mine is 9), they significantly shorten the distance between the hub flanges and make the front wheel lob-sided (although they reduce the lob-sideness of the rear). This must significantly weaken the wheels' resistance to buckling.

8, 9, & 10 speed Shimano cassettes are the same width, and run on the same hub.
The left and right spoke flanges on a rear disc hub are in exactly the same place as on a non-disc hub, so dishing is the same for disc and non disc.
Rear wheels carry more weight than front....if you can get as little dish on a rear as you get on a disc front, thats a cause for celebration.....so how is a tiny bit of dish on the front wheel a big issue?

[reohn2]

............I can see one disadvantage of disk brakes (particularly if you have a large gear cassette, mine is 9), they significantly shorten the distance between the hub flanges and make the front wheel lob-sided (although they reduce the lob-sideness of the rear). This must significantly weaken the wheels' resistance to buckling.

8, 9, & 10 speed Shimano cassettes are the same width, and run on the same hub.
The left and right spoke flanges on a rear disc hub are in exactly the same place as on a non-disc hub, so dishing is the same for disc and non disc.
Rear wheels carry more weight than front....if you can get as little dish on a rear as you get on a disc front, thats a cause for celebration.....so how is a tiny bit of dish on the front wheel a big issue?

I agree,it isn't an issue.
We've been running a tandem with discs for 4years now (albeit with40 spoke wheels) without problems other than a broken rear axle when we first bought the bike and which broke on the driveside.I'm convinced that it was a rogue axle that left the DT Swiss factory flawed.

[Brucey]

Rear wheels carry more weight than front....if you can get as little dish on a rear as you get on a disc front, thats a cause for celebration.....so how is a tiny bit of dish on the front wheel a big issue?

The front wheel dish isn't that tiny, and the weight loading is not the only wheel loading by any means.

Dished wheels lose lateral strength before they lose radial strength. Lateral loads on front wheels are not insignificant at times; MTB-ing is a good case in point. Fast tandem work is another. When disc brakes were first talked of for XC, everyone thought we'd be able to run lighter rims. It didn't happen like that; rims stayed the same weight more or less and significantly lighter rims tend to taco too easily even for XC use.

If you run 135mm 7s disc or 140mm 8/9/10s disc, with an appropriate dish for each, your front wheel is often more dished than your rear....

BTW rear disc hubs very often have the flanges ~2mm closer together than non-disc hubs; typically the NDS flange is moved inwards. Whilst this reduces dish and makes spoke tensions more even, it almost certainly also reduces rear wheel strength somewhat.

cheers

[531colin]

Rear wheels carry more weight than front....if you can get as little dish on a rear as you get on a disc front, thats a cause for celebration.....so how is a tiny bit of dish on the front wheel a big issue?

The front wheel dish isn't that tiny, and the weight loading is not the only wheel loading by any means.

Dished wheels lose lateral strength before they lose radial strength. Lateral loads on front wheels are not insignificant at times; MTB-ing is a good case in point. Fast tandem work is another. When disc brakes were first talked of for XC, everyone thought we'd be able to run lighter rims. It didn't happen like that; rims stayed the same weight more or less and significantly lighter rims tend to taco too easily even for XC use.

If you run 135mm 7s disc or 140mm 8/9/10s disc, with an appropriate dish for each, your front wheel is often more dished than your rear....

BTW rear disc hubs very often have the flanges ~2mm closer together than non-disc hubs; typically the NDS flange is moved inwards. Whilst this reduces dish and makes spoke tensions more even, it almost certainly also reduces rear wheel strength somewhat.

cheers

You can't use special cases to argue the general point.
With any standard set of disc hubs I have built, front wheel dish is considerably less than rear wheel dish. You mention a 7 speed disc hub...presumably a special made from an 8,9,10 hub with a 7 speed freewheel body grafted on and re-arranged spacers? .........and 140mm hub - not common on tourers?.
At the same degree of dish ~(inequality of tension) you can get a laterally strong wheel with a big (wide, deep) strong rim or a laterally weak wheel with a light (narrow) rim. I imagine XC rim-brake rims are already as light as possible ....any lighter, I would expect rear wheel taco-ing to become a problem before front wheel. I'm sure you could run a lighter front rim than rear with disc or rim brakes, if you wanted to.
Weight obviously isn't the only load on wheels, but it is the load that produces spoke fatigue in touring wheels....generally driveside rear spokes. If I ever see one busted front wheel for every twenty rear, I'll start worrying about front wheel durability.
I'd happily accept the left flange 2mm further in on a rear hub....much better than the left flange 2mm further out, or the right flange 2mm further in (thats probably more than the difference between road Shimano and Campag 9 speed). I suppose it makes the wheel marginally weaker in terms of lateral loads from the left side.....but not as weak as it is from the right side.

[Brucey]

135/7s/disc hubs are standard fitment on some bikes including (amongst other things) Carrera subways and the like. 135/7s/disc/non-disc has been a common standard for some MTB fitments for some years; for the manufacturers it is win-win; they get to specify a less expensive transmission, and they get stronger wheels using 'standard' rims that fit into a standard frame. What is not to like?

140/8s/disc or even 145/8s/disc hubs are not that common but perhaps they should be; they are a good deal stronger. I think they might go very well in a widened LHT for example.

I don't disagree with what you say for many, or most touring, uses even, but it certainly doesn't always apply; MTBs etc can see a very different set of conditions. Twisty, whoopy, singletrack, steep descents, bomb holes, and riding out of the saddle in medium gears is very stressful on the front wheel. Such use often sees front wheel landings, heavy countersteering when the forks are on full bump, and so forth. Certainly you can't go making the front wheel very much lighter than the rear before it starts to cause big trouble under such circumstances. By contrast you could do a lot of other sorts of riding on a much lighter front wheel without any worries.

And then there are those continental Johnnies and those others who like to load up the front of the bike, as well as (or instead of) the rear. Not too many of them hereabouts, but some rather than none.

I guess what I'm saying is that, as ever, it is surely horse for courses...?

cheers

[pete75]

Call me daft, but last night when I was unable to get to sleep I was pondering painting some grey shifters black.

And you called TT riders freaky.....

[mattsccm]

I don't think weight will be an issue even at pro level. Its easy enough to build a bike below the UCI limits anyway so all the barkes will be is ballast to bring the weight up. I bet the aero issue will be dealt with soon by clever integration of calipers into forks etc like they are currently doing with rim brakes.
Need ? who cares?

[Brucey]

even if so, the disc will still stick out into the breeze. And in case you think it will slice nicely through the air 'because it is thin', a) it won't, and b) the airflow won't be quite be going in the right direction over the disc for that, anyway.

The UCI weight limit is an interesting one. Whilst it exists, a professional rider would need a very good reason for riding anything heavier (slower..?) than that. Maybe they still do for P-R, but not elsewhere I think. Likewise why should they ride anything that is 'slower' in other ways?

And what about brake centreing etc on wheel changes? IME the disc has to come right within about 0.1mm if it is not to rub, which drives me nuts when swapping out MTB wheels as it is; I can't see team (let alone neutral) race service coping with that for a moment.

Professional cycle sport is still very important to the bike manufacturers for sales etc, but arguably the converse is no longer true; the days of bike manufacturers being anything more than minor sponsors of top-flight pro squads seem well and truly over.

In the old days Mr. Campagnolo's word with his sponsored teams (regardless of the nationality of the riders..) was enough to affect the outcome of the World Championships. If the bike manufacturers had their way, they would have overturned the weight limit years ago; the fact that it is still in force despite their numerous attempts perhaps speaks volumes about the relative influence of bike makers in cycle sport these days.

So it will be interesting to see if the UCI allow road discs (and they may not just because of peloton braking issues; there are enough stack-ups already without giving them another way to crash) and if they do, whether any really competitive teams and riders can actually be persuaded to ride them if -as there likely will still be- some measurable performance deficit and other problems.

If I sound anti-disc or something, I'm not. Not when they give benefits that are worth having/outweigh the downsides, anyway. I wouldn't have them on several of my bikes were it otherwise.

cheers