road disc frame sets

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ttakata73
Posts: 22
Joined: Fri Mar 23, 2012 11:36 am

by ttakata73

I agree with you.
Since motorcycle calipers are solidly mounted the rotors must float for even pad wear.
I am just saying they can do double duty to allow easier wheel swaps if bicycle rotors had enough float.
Interestingly pocketbikes have rigid rotors and floating calipers and cars are mixed.
I had a Kawasaki KLX250 with dirt and motard wheelsets.
The rims were different but with identical hubs and rotors wheel swaps were simple.

I suspect the mtb realm has standard offsets on the forks and hubs because I have an Avid BB5 setup and the caliper bracket has very minimal lateral adjustment allowance.
Also a brand A mtb hub will fit just as well as a brand B mtb hub in the same frame/fork (ignoring axle diameter).
I suspect the few road disc frames out now actually share this mtb standard because Shimano's road disc calipers look very similar to their mtb calipers.

If mankind can send (or fake in a studio) man to the moon; road discs will be sorted out.
I think as time goes on a generally accepted standard will fall in place for road bikes just like bottom brackets....hahaha, we are doomed.

I buy into the aero trend even though I don't have an aero bike or even race.
Hopefully in 2 years I can get a nice carbon, aero, sportive, disc, thru axle, with Di2 bike for under $3000.
Sure, I am a marketer's dream customer but such a new tech bike will surely make me enjoy riding more than my 1998 road bike.

tinozee
Posts: 764
Joined: Wed Jun 01, 2011 7:53 am

by tinozee

The other day i was riding my winter bike, a ridley cross bike with sram red and trp mini v brakes. I have it setup for road riding in my area. It's sweet because it can fit 30mm studded tires in shit ice and snow, and can also run 25mm tires on dry days. The other day I was on one of a few steep descents and it had started raining. I was with a fast rider and we were kinda bombing the hill. At one point we came up on a crossroad and a truck was sort of hesitating as he crossed, forcing me to use the brakes. The mini Vs lock up real easily, so I was basically check sliding several times like I was on a brakeless fixie. That ridley is a bike that I would love to have discs on! The modulation that you can still have in the wet would really help in that type of situation. On the other hand, I'm fine 100% of the time on regular road calipers even descending in the rain and it's not really worth the weight/aero trade off just yet imo.

I am certainly interested in seeing how they progress for pure road riding and will make the switch if they evolve more. For commuters or cross, it's a no brainer to go disc already.

by Weenie


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Causidicus
Posts: 320
Joined: Tue Apr 17, 2012 11:20 am

by Causidicus

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Last edited by Causidicus on Tue Jun 17, 2014 11:32 pm, edited 1 time in total.

xnavalav8r
Posts: 2594
Joined: Mon Jan 21, 2008 12:09 pm

by xnavalav8r

You count one instance in thousands where neutral support cost a rider a placing (maybe) and call that evidence? If anything it was an anomaly. Besides, that issue had everything to do with the individual mechanics being incompetent and nothing to do with the wheel. And, if you believe conspiracy theories, some have claimed that bad wheel change was intentional. I just think the pressure of the moment overcame the mechanics.

In this interview, Evans says as much himself.

http://velonews.competitor.com/2009/09/ ... elta_97851

xnavalav8r
Posts: 2594
Joined: Mon Jan 21, 2008 12:09 pm

by xnavalav8r

eric wrote:If January's race was the one in Rome, it was very flat. The "run up" had maybe 2 meters elevation gain and the rest of the course was dead flat. And it was very muddy.

I don't think he'll run discs on a hilly course that's not sloppy wet. Two full bottles' weight is noticeable.

Looks like 140mm discs front and rear.


That was the BPost Trophy race in Baal, Belgium... not flat. Cold, wet. mud, sand, uphill, downhill...

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mattr
Posts: 4671
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

ttakata73 wrote:I suspect the mtb realm has standard offsets on the forks and hubs because I have an Avid BB5 setup and the caliper bracket has very minimal lateral adjustment allowance.
Also a brand A mtb hub will fit just as well as a brand B mtb hub in the same frame/fork (ignoring axle diameter).
I suspect the few road disc frames out now actually share this mtb standard because Shimano's road disc calipers look very similar to their mtb calipers.
Fraid not. The only standards are the mounting to the frame (post or IS) and the mounting to the hub (spline or 6 bolt).

Everything else is fairly random. Disc diameters (metric, inch and pain in the arris sizes, 140, 160, 163, 180, 183, 185), thicknesses (2 and 1,8) and offset from locknut to disc varies enough to make some combinations rub the caliper/not function at all.
Just think about the road issues, such as rim width or cassette position (distance from dropout to top sprocket, yes that varies by a couple of mm) but with no barrel adjuster or qr to open (or close) the caliper/adjust the mech.

mattr
Posts: 4671
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

xnavalav8r wrote:No. Not at all. In rain and freezing conditions, which I rode quite frequently,.<snip>
So, you are effectively building your entire bike around things that happen (to the vast majority) incredibly infrequently.
Sort of a "one bike to do everything" scenario?

mattr
Posts: 4671
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

Oh, and FWIW, I'm neither pro, or anti disc brakes. I'd just like to see someone admit that the only reason they are coming (at racing/UCI/NGB level) is so that manufacturers can make more money.

Which so far, is the only argument that seems to stack up to any serious poking.

xnavalav8r
Posts: 2594
Joined: Mon Jan 21, 2008 12:09 pm

by xnavalav8r

mattr wrote:
xnavalav8r wrote:No. Not at all. In rain and freezing conditions, which I rode quite frequently,.<snip>
So, you are effectively building your entire bike around things that happen (to the vast majority) incredibly infrequently.
Sort of a "one bike to do everything" scenario?


People ride infrequently in rain? Most cyclists I know ride rain or shine. Sometimes a sunny day turns to rain unexpectedly. My point was, no matter the weather conditions, the disc brakes worked every time.

The "snip" you took from my statement suggests that I am talking about freezing rain conditions. But the actual statement was pointing out that disc brakes performed better in rain and/or freezing conditions where rim brakes often (usually) suck. Perhaps I should have stated it that way.

eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
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by eric

I'm agnostic on road discs myself. But I think they will be better in some circumstances (serious rain riding, unconfident descenders) and not as good as rim brakes in others (weight, aero, neutral wheel support in some races). For some people the advantages are more applicable to their riding, for others the disadvantages are more applicable. I think that "discs are awesome!!!1!!" or "discs suck!" both oversimplify the situation. While I am sure that some manufacturers hope to sell more bikes with discs, I don't think that'll happen to any significant amount as most sales of disc bikes will replace a sale of a rim brake bike. And in any case, hoping to sell more bikes does not change the advantages (or disadvantages).

Personally I am happy with the performance of my rim brakes (especially the EEs with light springs and Red levers) on descents. The rim brakes on my rain bike work ok in the rain, but I am used to clearing the rims periodically. If I had to do more rain riding than I do now I'd consider discs for a dedicated rain bike.

It'll be interesting to see what happens when the first person runs a disc bike in the local NCNCA road races.

Gunjira
Posts: 32
Joined: Mon May 30, 2011 11:41 am

by Gunjira

Firstposter here, this debate drove me out of lurkerdom. I personally am in the process of getting a custom made stainless steel bike centered around discs, couplers and di2.

If you are not emotionally invested somehow this needn't be a either or issue. I think the facts are on the table and from a WW perspective calipers rule. I like the performance in the rain an something that hasn't been mentioned enough - modulation. For the right reasons that can be enough motivation to put discs on a road bike, but its not the epoch changing innovation that marketing makes it to be. Even though the technology is not in its infancy due to the knowledge transfer from the mtb, disc road brakes still have a long way to go. Maybe they are at a stage like calipers where, when dual pivots first came out. I don't know how long it will take or how long manufacturers want to introduce one upgrade at a time, but it will only get better.

So if the standards how calipers and rotors attach to frame and rotors doesn't change dramatically, choosing a disc brake equipped bike now is not incredible risky. Just upgrade the brakes and buy a good wheelset once they finally come along and the frame will be ok to use for the next couple of years. Maybe switching the fork to a through axle is another meaningful upgrade, but apart from wheels that's not big bucks.

For racing, I understand the issue the UCI has with mixed performance and wouldn't want to race in a mixed peloton myself. That will probably be an all or nothing decision. Once you have self-centering discs with an option to tweak the adjustment near the lever, the neutral support problem will go away. Around me, everybody is already using inline able adjusters near the lever.

I bet that in 10 years time more than half of WW will be owning at least one disc brake equipped bike.

shimmeD
Posts: 544
Joined: Thu Jun 28, 2012 10:52 pm
Location: eNZed

by shimmeD

bm0p700f has gone silent since starting this thread. If I'm not wrong he wanted to hear what disc framesets are available and quoted a steelie. This thread has now degenerated into disc vs rim brakes yawn yawn yawn :unbelievable: :roll:

bm0p700f, do you think you can pull this thread back into line, please? :doh:
Less is more.

Posix1b
Posts: 40
Joined: Mon Dec 09, 2013 4:16 pm

by Posix1b

What's funnier, the entire cycling media, the big ones, you know whom I'm talking about, all have but shut up, completely stopped talking about discs on road. All these journalists nothing but slaves to bike manufacturers who are willing to pay for adverts, Shimnao and Sram.

Nebby
Posts: 60
Joined: Tue Aug 20, 2013 12:53 am

by Nebby

Not sure there's much to hype right now, as Shimano's r785's are out but not readily available and even the road disc frames and bikes aren't exactly in mass production. SRAM had it's major recall and there was a lot of coverage there, but nothing new from them since then. Maybe it's just me, but until more bikes come out with disc road I'm not sure what you expect the "entire cycling media" to be talking about?

Personally, I'm looking forward to building a commuter/gran fondo bike with the Shimano r785's. I'm a major fan of the shimano xtr brakes for mountain biking and everything I've read indicates that the same amount of modulation and performance are in the new road disc set. I also like the fact that the expensive carbon rims on the bike won't be a wear item anymore. For sure, it's not going to be a weight weenie build, but it is what it is ;)

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bm0p700f
in the industry
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by bm0p700f

ShimmieD I was thinking the same thing. I am firstly looking for a disc brake frame for my wife, then later this year for myself.
It will need to be able to take Di2 as I have the R785 shifter on order. The wheels will be the Ryde Pulse comps disc specific road rims 28H on Shimano CX-75 disc hub and 160mm rotors. Ultegra 6800 Di2 will be used. I have all the kit just no frame and fork. The spec for my bike will be the same unless campag do something for disc brakes in 2015. There are two a chinese open mold frameset I could buy. One is BB30 only and that does not appeal and the Hong fu one can come in a BSA thread and looks O.K.

Plenty of complete bikes about but that's the last thing I want for my wife or for me. For me the problem begin (for my wife a open mold frame will fit well in 52cm size like the Hong fu one). I ride 58-60cm traditional frames mostly with a 58 or 59cm top tubes, 120/110 mm stems respectively and 73.5 degree seat angles. The hong fu frame in a 56cm size has a 56cm effective top tube and a 73.5 degree seat angle. This will be too short for me unless I use a 140mm stem. So currently for me I have a choice of a heavyish steel frameset or a chinese frameset that will be a compromise on the fit front. Maybe I will have to get a custom framset made.

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