tetonrider

you won't really notice a difference but if they put in the new style cable, it will probably fray (not really fray but the coating comes off and messes it up) again and lock things up. old DA cables were also pretty darn good (not quite as smooth, but still very good) with no fraying/shedding issue.

you might want to check because as you well know it is super inconvenient when a shifter locks up.

or just go di2. ;-)

tetonrider

i was unable to build a 6.8kg cross bike last fall--and that was with a single chainring, no FD, s-works frame, and some other light parts. wasn't even close. yeah, the cross tires are another pound, but i was around 17.5 i think.

IMO, mechanical discs are not good. the pads wear and then feel spongy or worse. hydraulics or bust, for me. (there is enough wear during a single cross race that mechanicals decrease in braking power, noticeably.)

anyway, is racing an element of your life, still? (don't mean this to come off in any way other than an honest question--just can't remember if you are still actively racing.)

you willing to take the aero penalty of discs?

i can think of one occasion where i would have liked more power (in a race), but i looked around and felt pretty happy that we all had equally little power.....so there were no sudden movements.

i hope disc brakes do not become a thing in road racing. say goodbye to neutral wheels that actually work w/o brake rub!

shovelhd

Road discs are inevitable. No turning back now. I honestly don't think I'll ever get there. New frame, wheels, shifters, brakes. Ouch.

mike868y

so i ordered some cable and housing sets a few weeks ago but haven't installed yet. i'll have to check, but i think they are the ptfe coated ones. i'm on 6700, should i use standard cables instead of the coated ones?

shovelhd

6700 should work great with coated cables. I have Jagwire coated cables with 5700. Works fine.

echappist

the coating eventually wears off and gunks up the housing

mike868y

how long are we talking? i'd rather spend the extra $10 on a couple normal cables then have to replace all my housings and **** after a few months.

tetonrider

specialized is REALLY pushing their tarmac disc right now. got offered an insane deal on one...totally crazy.

but....i just don't want it.

i know it is coming and eventually i will probably have to switch. not being a curmudgeon -- i just think there are many drawbacks that most people are not thinking about, and they're trade-offs i prefer not to make (until forced).

for me, road disc is a solution to a problem i don't have.

if i commuted by bike in seattle my position might be different.

and....i ride a hydraulic disc cross bike on the road sometimes + have discs on MTBs, so i'm no stranger to what they do well.

tetonrider

11,942 shifts.

seriously, though, it is hard to predict. depends on how much you shift, conditions you ride in, cable routing, how you maintain your bike, etc.

i put 9070 on my training and race bikes last spring. i noticed at batten kill the front brake of my race bike (PTFE DA inner w/ Nokon inner & outer housing) was shedding. maybe 18-20 races. shipped all over the country. (just mention because the bars are removed often and perhaps it caused some tight bends in the cable.)

on my training bike that sees many more miles, i have no issues.

YMMV.

shovelhd

You're running a mixed system though.

burger0014

Does anyone use race dots or do they look stupid? Safety pins work but why not fix something that isn't broken. RaceDots?

shovelhd

We've been over this before. It depends on the official. If I'm inspecting numbers at the line and you show up without pins, I might tug on your number. If it detaches, I'm going to ask you to pin it up. If you miss the start because of it, well that's life.

Ygduf

race dots, from what I've seen also just kind of suck and don't keep the number flat.

super77, 4 pins.

mattm

no - 7 pins, and save the planet to boot!

Duke of Kent

I am. But almost entirely on the MTB. A bit of cross.

Thus, I have a boat load of disc wheels, all carbon. Three pairs of tubulars, two pairs of clinchers. Don't own any aluminum wheels anymore.

Due to where I lived while stationed in GA and NY, I more or less stopped racing on the road; there were no road teams, no organized group rides, nothing. Lining up at a race without teammates, unless you're a world class dude out to lap a crit 3 times, isn't fun. I could, however, drive a couple of hours to great MTB and cross races. Also, due to the demands of my job, I didn't have time to train like I did before the military. Thus, shorter races were better for me.

Of course, now I'm a civilian again, and stronger than I was before...

spectastic

I don't understand how a cable disc brake loses braking power throughout a race. does dirt get into the cable housing causing the thing to get squishy ?

tetonrider

pads wear. mech disc setups do not self-adjust in the way hydraulic systems do. essentially the pads require longer travel as they wear before initial bite (+less power).

all mech systems that exist today (that i know of) have their adjustment at the caliper, so it is not just a matter of reaching down during a race/ride.

it is especially noticeable when things are wet and/or dirty, so less noticeable on the road (but probably an issue in the very conditions people most pine for disc brakes on the road).

go try a bb7 setup vs a hydraulic setup for 5 laps on a cross race and you can feel the difference. it's not subtle.

tetonrider

we may have different definitions of fun, Duke.

racing longer doesn't necessarily entail training longer.

spectastic

I don't race cyclocross. I'm building a do it all bike for touring, commuting, and light trails. the bike has alfine 8, which comes in 135 rear spacing, and most frames with that drop out spacing are disc. I could try filing it down to 130, but would much rather not... anyway, I would avoid disc brakes altogether if at all possible, because v brake pads supposedly last a lot longer. But if I'm stuck with disc brakes, I'd rather get something cheap, and mechanical setups appeal to me as something simple and easy to maintain.

what about those cheap ebay disc brake sets? they're like $30 for the lever, brake, and rotor (maybe even cable). for basic needs, are they adequate, or bad news?

shovelhd

Di2 and $30 brakes. Makes sense to me.

carpediemracing 

We have BB7 on our road tandem. They seem fine. I think you can get a set for $70 with rotors? I think I did, for my yet-to-be-assembled mtb. Older rotor cut price dramatically.

Currently tandem BB7 (oem) are paired with 10s Ergo levers so no special lever. They use "downhill" rotors (dunno what that means but that's what the shop guy said). Maybe 180mm? 220mm? Whatever larger than the normal one. Max speeds 45 mph, bike/riders weight just under 400 lbs for many rides, probably closer to 340 lbs if we were to go out now. No problems with braking.

Apparently on very fast tandem descents the rotor gets melty. There's a shot of a tandem here on BF, ridden by BFers, where the rotor looks like it's flopping over at the top. Might be video distortion etc but looks weird. This is on a tandem so 70 mph and 300-400 lbs of bike/riders and prolonged descending.

After my initial "I don't like discs" knee jerk reaction to the road disc rule thing I decided that my next bike may have discs. Reason? Wet weather braking. Also no questions about carbon/aluminum - I can get used to braking reaction regardless of which wheel I'm riding.

topflightpro

A buddy of mine won a set last year. He used them once, and he didn't seem impressed. The second time he went to use them, he wasn't paying attention when putting them on and let them slam together. Apparently that is a No-No, and they broke.


They are your brakes. Do you really want to go cheap and risk them not working when you need them most?


At this point, if I were to buy a new bike, I'd probably go with one with discs. I am convinced that in a few years, it will be nearly impossible to find a frameset for rim brakes - just look how hard it has gotten in cross in just two years. It's not necessarily the direction I want to go, but it really seems to me that is the way the industry is going.

canuckbelle

What are the downsides, if I may ask? I'd think that the pros for those with carbon wheels would be really big, no?

globecanvas

Downsides: weight, aero, cost, compatibility, and forget about neutral wheel support, even if the rotors are the right size there's no way your calipers are going to happen to be adjusted perfectly for some random wheel.

Maybe everything will be discs in a few years, I don't know, but it's not all upside.

caloso

8 pins.