Alloy VS Carbon Road bike

creaky

XMAS Plumper
I'm assured by owners and industry types that a well maintained cable setup is ample for road use with skinny tires and small contact patch. I have no experience with road or cable discs.
Cables will have ample 'power' but you lose the modulation which is, if anything, more critical with less overall grip e.g. skinny tyres in the wet.

Still, much better for long-term all conditions use than rim brakes (IMO/IME)
 

mtb101

Likes Bikes and Dirt
The Defy 3 Advanced is part of the factory sale, the next model is not so there is close to 1K jump.


They are all cable at that price point in "name" brands anyway.
I agree which is why I'm spending more on a hydro equipped gravel grinder although I'm assured by owners and industry types that a well maintained cable setup is ample for road use with skinny tires and small contact patch. I have no experience with road or cable discs.
you remember descending with the lovely even beautiful 1 finger operation of the xt type mtb hydros - a little tap here, over a jump, tap into a corner, sweet as ..... well on the roadie + mechanicals you don't have that, you're on the hoods so there's more strength commitment to get similar levels of braking. not to mention the total lack of modulation. so problem for us mtb riders is that's our standard. plus we ride roadie likes its an mtb anyway, you know a few bunny hops here and there, occasional sick turn.

now you might say roadie aren't as demanding as mtb on brakes, well it can be especially descending at 80+ks down mountain, or simply pumping through traffic. aren't easy for us mtbers to go backwards on components
 

Calvin27

Eats Squid
Hardest thing about road riding was understanding why people needed to give signals. Running a MTB downhill section, you just hoped the dude behind you knows what they are doing. It was especially hard not to laugh when they pointed at these little pissy pot holes. I thought they were always telling me to bunny hop it!

Anyways cable discs are still a mile better than rim brakes ime/imo. The main issues are a rim can pick up a lot more water than a disc, and grit can render a wheel useless, whereas a disc is at worst a $20 replacement bolt on and/or pads. Hand placement is irrelevant because I actually think on the drops (where you should be on the descents) you have a lot more power to grip and it's in a more natural position.
 

The Duckmeister

Has a juicy midrange
you remember descending with the lovely even beautiful 1 finger operation of the xt type mtb hydros - a little tap here, over a jump, tap into a corner, sweet as ..... well on the roadie + mechanicals you don't have that, you're on the hoods so there's more strength commitment to get similar levels of braking. not to mention the total lack of modulation. so problem for us mtb riders is that's our standard. plus we ride roadie likes its an mtb anyway, you know a few bunny hops here and there, occasional sick turn.

now you might say roadie aren't as demanding as mtb on brakes, well it can be especially descending at 80+ks down mountain, or simply pumping through traffic. aren't easy for us mtbers to go backwards on components
Exaggeration much? To say that cable discs have no modulation is pure crap. The pads are the same compounds as the hydro cousins, and being much harder than rim brake pads is where a huge part of the modulation comes from. What cables lack that you get with hydros is the almost effortless efficiency. Cables have friction, which takes more finger effort to overcome to make the brakes do their thing. Cables also stretch, which contributes a bit of modulation, plus in the drops, where you get your best hand position, you have a considerably longer lever to play with, which also allows finer adjustment of the force you put through the brakes.

The two biggest disadvantages of cables are the cable friction, which gets worse if you fill them up with crud, plus the brakes are more fiddly to adjust and don't self-compensate for pad wear, so you have to periodically adjust them. In those regards they're no different to rim brakes.
 

mtb101

Likes Bikes and Dirt
you forgot to mention that hydro can generate much higher braking forces than a cable operated disc system. they also have superior modulation compared to mechanical system.

as I said if you're an mtber then hydro brakes are the norm - along the modulation, ease of adjustment and superior braking under high loads.

now you go ride a mechanical disc roadie or cx the stopping power aren't there, the modulation aren't there, what's there is a poor version of a hydro.
 

Haakon

has an accommodating arse
Get the carbon.

I have a 2015 Defy Advanced Pro 2 - 11 speed 105 and TRP cable discs. There are three grades of Defy carbon frames - entry has an alloy steerer and lesser carbon, mine is the mid with a carbon steerer but not the intergrated seatpost of the top model.

The brakes are better than rims, but not as good as hydraulic (I recently splurged $500 on the shimano hydraulic brake/shifter, and it is a massive improvement again - if you can find/justify the cash, I'd recomend a hydraulic brake version). The 5800 105 group is perfect.

For your dollars, stretch to the 105 equipped carbon - a 2015 Defy Advanced 2 if you can find one in your size will fit your budget.
 

Haakon

has an accommodating arse
you remember descending with the lovely even beautiful 1 finger operation of the xt type mtb hydros - a little tap here, over a jump, tap into a corner, sweet as ..... well on the roadie + mechanicals you don't have that, you're on the hoods so there's more strength commitment to get similar levels of braking. not to mention the total lack of modulation. so problem for us mtb riders is that's our standard. plus we ride roadie likes its an mtb anyway, you know a few bunny hops here and there, occasional sick turn.

now you might say roadie aren't as demanding as mtb on brakes, well it can be especially descending at 80+ks down mountain, or simply pumping through traffic. aren't easy for us mtbers to go backwards on components
This is very much my experience. I hated rim brakes on my first roadie with a passion... Hopping into a hairpin at 70 clicks and having the rear wheel randomly lock was not fun and very frustrating as the feel and modulation required and expected simply wasnt there.

The hydraulic disc brakes I now have on the roadie have restored my basic standards that I developed from my moutain bike's brakes.
 

The Duckmeister

Has a juicy midrange
You forgot to mention that hydro can generate much higher braking forces than a cable operated disc system. They also have superior modulation compared to mechanical system.

As I said if you're an mtber then hydro brakes are the norm - along the modulation, ease of adjustment and superior braking under high loads.

Now you go ride a mechanical disc roadie or cx the stopping power isn't there, the modulation isn't there, what's there is a poor version of a hydro.
Try reading properly what I wrote (and I fixed your grammar).

I never said hydros aren't better; what I said was that cables aren't as bad as you paint them to be. Hydro might in theory be able to generate higher braking force, but in the real world, especially on road, the tyres impose a big limit on how much braking can actually be applied, and in the dry there's actually very little difference between rim brakes, cable discs & hydro discs in terms of outright stopping power.
 

Haakon

has an accommodating arse
Cable discs are pretty decent when the cables are perfect. The cables are rarely perfect...

With the roadie, it the was rear that was most problematic - full length outer with a few bends. Front always had a better modulation.

But even with perfect cables, you still get a bit of that notchy feel through the lever travel - I never got used to it and am really enjoying being back on hydraulic.
 

andrew9

Likes Dirt
My 105 rim brakes always had better feel, and a lighter touch, than my MTB’s Elixar or Hayes with 203mm rotors ever did.
I actually didn’t mind either of those disc brakes either, it’s just a good rim brake is very powerful indeed.
My Zees laugh in the face of anything else I’ve used, but I wouldn't want that kind of power on the road, but it is nice to have a feather light touch.

The only thing I dislike about rim brakes is when they get gritty on a wet ride, grinding away my nice wheels.
In the wet you do get a change in power, but it coincides with a big reduction in grip from the road being wet too.

When I had rim brakes on MTB's, and I had lots of them, there was no end of trouble with wheels going out of true, pad alignment and rims shredding bits of alloy.
Road rim brakes seem to avoid these problems somehow, probably due to getting better treatment. I only had to clean a bit of alloy out of a pad once, when my wheels were still new

All that being said, for an everyday commuter, I'd probably get discs too. I just wanted to defend the idea that rim brakes suck
The Shimano hydros aren't that expensive, $550 on Merlin, when you consider the 105 rim brake equivalent is $270 odd
 
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Haakon

has an accommodating arse
But, on the original question - I would say carbon. But Giant make excellent alloy frames and new alloy dsc defy is meant to be a standout in the alloy crowd.

At this price point you'd go for the best deal.
 

nakedape

Likes Dirt
Do what I did: find a carbon frame that you like the look of. Buy it. Build what ever you can afford (105 groups can be had for about $500, wheelsets from $300). Then ride it.
 

XYGTHO

Likes Dirt
Do what I did: find a carbon frame that you like the look of. Buy it. Build what ever you can afford (105 groups can be had for about $500, wheelsets from $300). Then ride it.
Thought about doing that. But it does add up, brakes, bottom bracket, headset, bars, seat post, seat, groupset. End up costing the same or more. Could be a better build, but probably less resale value. Also Giant locally have great mechanics and warranty and servicing or something for so long? I do like building, and have done so for my last two mtbs.
 

slippy

Likes Bikes and Dirt
Long time MTBer, fairly recent roadie. Carbon frames are so comfortable on the road compared to alloy. Lay-up blah blah flex blah stiffness blah blah - currently riding a Specialized Tarmac which is known for being a fairly rough unforgiving carbon frame, it beats alloy out of the water for comfort. I would never recommend alloy on the road.

As for disc brakes, I call kool-aid. I came from a MTB with XT discs 8" front and 7" rear. My roadie has rim brakes (Sram Force) and not once have I wished for extra braking power, and I descend some steep hills. Why any self respecting roadie would put a huge slab of rotating steel on a lightweight wheelset is totally beyond me. And in case you think I'm full of shiz, how many riders in the TDU were sporting disc brakes this year? Precisely zero.
 

spoozbucket

Likes Dirt
You need discs because they look rad and they make track stands easier, just don't do them in NSW or you might get fined, hahaha!
 

scblack

Leucocholic
Discs are currently allowed in the TDU and any other WorldTour race the teams choose. From memory they can choose two races per year to use discs. This is a transitional phase until they are used/allowed in 2017.

I have two roadies with rim brakes and have never wanted discs as such on a roadie. They may be better in wet conditions, which is undeniable. But the fact remains the skinny tyres on a roadie limit the effectiveness of ANY braking system due to the limited grip of the tyres.
 

ducky1988

Likes Dirt
you could wait a couple of months until the new models come out. Then the better model carbon will drop a bit.
I always choose the spec over the frame. What's the point of having a Lamborghini with a charade engine in it?
 

Psimpson7

Likes Dirt
Discs are currently allowed in the TDU and any other WorldTour race the teams choose. From memory they can choose two races per year to use discs. This is a transitional phase until they are used/allowed in 2017.

I have two roadies with rim brakes and have never wanted discs as such on a roadie. They may be better in wet conditions, which is undeniable. But the fact remains the skinny tyres on a roadie limit the effectiveness of ANY braking system due to the limited grip of the tyres.
Having swapped to a Tarmac Disc from my previous roadie I am 100% happier with the discs compared to the ultegra rim brake setup I had before.

I can do stoppies now! Which clearly is important!

The biggest advantage is the ease of which you can stop. One hand on one brake from the hoods on a fast downhill results in an effective and controlled stop. I could never do that on the previous brakes. I would always have to be on the drops and on both brakes.
 

scblack

Leucocholic
Having swapped to a Tarmac Disc from my previous roadie I am 100% happier with the discs compared to the ultegra rim brake setup I had before.

I can do stoppies now! Which clearly is important!

The biggest advantage is the ease of which you can stop. One hand on one brake from the hoods on a fast downhill results in an effective and controlled stop. I could never do that on the previous brakes. I would always have to be on the drops and on both brakes.
Furry muff. I do have to admit not having ridden a roadie with discs.

I do still see it more a marketing exercise to sell more new bikes. Better braking performance has to be a good thing - but how necessary is it? I won't be buy one soon - but if it works as well as you say my next bike will be tested with discs for sure.
 
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