Steve B.

An interesting article on the Cervélo website and I think they only make carbon bikes ?. The pie chart shows how small a portion of overall rider comfort is from the vertical compliance of a frame. I’ve seen this before, that so many other factors - tire size and psi, wheel design, saddle used, bar tape, shorts, etc.... are as, or more important than the frame.

Can we feel the difference between materials ?, yes and that affects what we like to ride. I read somewhere that carbon is really good at damping shock transmitted thru a frame. Aluminum less so. Steel and titanium are in between those two. But the feel is very subjective.

https://www.cervelo.com/en/ride-quality

redlude97

My carbon superx with the dreaded bb30 also has never creaked. Proper prep and install of generic bearings with loctite 609. Gets ridden hard in mud and water

mstateglfr 

Yeah...I'm just not the dramatic a rider, I guess. I haven't been in a descent with my 1" steerer road bikes and lacked confidence or felt unsafe. my old gravel frame, with a 1 1/8" steered never left me feeling unsafe or unsure.
I dont feel safer or more confident on my current gravel frame with a tapered steerer and 44mm head tube.
Perhaps I dont ride dynamically enough to experience the unsafe feeling of a 1 1/8" steerer, or perhaps the gravity of the situation is overblown.
I would think geometry would play a larger part in confident descending. For confident descending, things like trail and front center measurement seem more critical than an overly stiff bottom bracket or massive head tube junction.
Maybe I'll come upon a time when I wished for a frame that is as laterally stiff as a board, but so far that hasn't come up.

As for you referencing Cannondale as the brand that is trying to market suspension as a technology in their frames due to stiffness- not sure why you left out Trek and Specialized. You bash Cdale for focusing on stiffness then having to engineer in comfort- why leave out Trek and Specialized? Seems odd to rant about one brand only when two major brands are pushing comfort tech.

HTupolev

That's what the marketing says. But as someone who rides frames with widely disparate characteristics in spirited road rides, I can't agree. Sure, if the frame's properties lead to bad specific behaviors like speed wobble, changing them is significant. But as long as the frame is reasonably well-behaved, further stiffness isn't overly relevant to road handling.

In yesterday's road ride, when we cracked 50mph on one of the descents, my steel bike tracked rock-solid like always, 1" steerer and 7/8" quill stem and all.
My '83 Miyata 710 is, in most respects, flexier than my Emonda. But its geometry is very similar, and the way it responds to steering is just about identical.
And when I'm leaned far in a corner on a vintage steel wet noodle, it's the tire feedback that makes me nervous, I don't really notice frame flex at all.

JF69

Titanium.

Awesome ride quality, strong yet light, looks great too (if that's your thing)

MugenSi

I have a 2017 Felt VR30 gravel bike fitted with 28mm tyres on Fulcrum DB5 wheels and 5800 groupset. Its my go to bike for 90% of the year, very comfortable, versatile, great gearings (46/30 chainset with 11/32 cassette) and out of the 4 road bikes I own, its my favourite. When buying this bike I could have bought the VR4 which is the carbon version with 4700 Tiagra groupset but I wanted alloy as it can stand up to abuse more and less likely to get damaged and the weight difference between the two was negligible (less than 0.4kg)

I also have a 2015 S-Works Roubaix (SL4) with carbon wheelset and R8050 Di2 groupset that I sort of have to force myself to use in summer. Its a beautiful bike, much lighter than the Felt (7.2kg v 10kg) and faster. Its set up almost identically to the Felt with more or less identical reach/stack etc but I just prefer the Felt for some reason.

I also have a Planet X Spitfire titanium bike with 6800 groupset which gets very little use, its a lovely bike but if I were honest with myself I have no use for it and should sell it.

I also have a 2018 Cube Attain (entry level bike with Claris) which I use on the turbo trainer and take with me if we are going away for weekends during the summer etc. Its such a nice bike also, the frame is very sweet, comfortable and rides really nice, The biggest problem with the bike is the big gaps in the gears, it has a 50/34 compact chainset and an 11/36 8 speed cassette. I plan on changing the cassette to an 11/30 which should take out some of the huge jumps but like the idea of the 36T as a bail out gear for really tough stuff. I prefer this bike to the PX titanium bike as it rides nicer even on its really cheap Alex rims and wired tyres.

I will most likely keep the Roubaix long term for summer use and change the Felt at some stage but what ever I do replace it with, it'll be alloy.

fraba

I agree that no other material than carbon offers such possibilities to frame designers. I am a fan of carbon. However, intinctively (I have no experience riding an aluminium gravel bike) I tought that bigger tires with lower pressure would reduce the advantage of carbon over other materials on gravel/off road. On tarmac, the capacity of carbon to soak small vibrations while being laterally stiff is certainly a big advantage when riding on small width/high pressure tires. I love my open UP on fat 650B 47mm tires but would be curious to compare the same tires with an aluminium frame. Someone did this kind of comparaison?

Fox Farm

Take a look at a Lynskey for a Ti frame on gravel.

Fox Farm

It is more than just frame material, geometry in particular for a gravel bike is critical. I ride a steel Ritchey Outback and really like this frameset/bike. I also own a carbon Orbea Orca (road only) and titanium Merlin Extra Light (road only). Putting the Ritchey into turns, particularly at speed, you notice the intelligent well worked out geometry of his frames. It is not twitchy and is very stable, but much more sporty feeling than other gravel bikes that I have been on, particularly due to the head angle. Just my 2 cents...

shoota 

I can positively state that is not true.

biketampa

not all carbon bikes have press fit bottom brackets

shoota 

I've always wondered how that HDA affected the real world feeling of the Outback. Glad to hear my suspicions are confirmed.

Fox Farm

I am not a frame builder (although that is on my bucket list of things to learn), but I find that on the Outback, the front end is fast and the rear is stable. When riding it on the road and pushing the bike into a fast descent and carving turns, it feels so different from my road bikes. The rear end stays planted, so to speak.

mstateglfr 

If the Ritchey came in a size that fit me, it would have 100% been a frame that I didnt just heavily consider, but would have almost certainly purchased. I geek on Ritchey stuff hard. The only downside is 40mm max tire which is antiquated. I would have gotten over it and continued to ride 40mm tires though.

The 73degree HTA and 47mm fork offset in the largest size is 60mm of trail. That is the same trail as my gravel bike with a 72.5 degree HTA and 50mm fork offset. Its certainly a departure from where a lot of gravel frames have gone in the last year or two.

Steve B.

Cervelo disagrees with you. Go look at the chart they have on the site and notice where the frame sits in the general scheme of ride quality.

shoota 

I can't find it but I wouldn't believe them anyway lol. My butt and personal experience don't lie.

Steve B.

https://www.cervelo.com/en/ride-quality

Our individual experiences are what is known as anecdotal. I cannot recall what or where I read it, but somebody did a stiffness test a few years ago (Damon Rinard maybe ?) to try to determine if such things as vertical and lateral stiffness in frames could be felt by the rider. I recall many heated discussions on the internet at the time but generally the consensus was that given the use of aired-up rubber tires, saddles, bar tape, padded shorts, etc... all essentially combined to eliminate a riders ability to feel a difference in the vertical stiffness between frames.

That's not to say that you don't feel the difference between frame materials. All experienced riders can feel that shock and bumps are transmitted thru the frame in different ways, and I've read that carbon is good at soaking up shock while aluminum is not. My experience with multiple carbon, aluminum, steel and titanium frames is not that clear cut. I'm a clyde and am likely less sensitive to how a frame transmits shock. Other riders (like a buddy I road with today) are significantly more sensitive as you might be and I think that's what drives peoples opinions. Which are just that - opinions.

biketampa

I guess I just assume my bikes are going to get some superficial damage so I just don’t feel it’s worth it taping things up.

dwmckee

Certainly, but I was sticking to teh OP question about Carbon vs. Aluminum as a frame material, not geometry, tires, wheels. etc... When you have wider tires at the right pressure, well designed geometry AND a carbon frame,well, you have a custom built Open! It don't get much better. And Open is made by Gerard Vroomen who founded Cervelo then left to form Open. He also is the main designer for 3T.

Fox Farm

Wow, how tall are you? I am 6'3" and the XL fits me fine. I use a 12cm stem. Because I also ride the bike on the road, partially for commuting and also for getting to different trails in the rural landscape, I like the fact that it feels sort of fast like my road bikes. As for noting bigger than 40mm tires... I don't know, I run 38s regularly. I guess if I were riding in a particularly rocky area, like when I lived in northern Utah, I could see the benefit of larger tires. I was a bit torn between the Ritchey and the Ibis Haka, which can take larger tires and even 650b but had wanted another Ritchey for some time. I have had a Road Logic which is a great bike and in the very early 1980s, i rode on of his early mountain bikes, so I had some history with the brand. Also the same with Ibis so it was a bit of a toss up.

DeadGrandpa

I ride a a Jamis Renegade Expert, which is probably good for pavement or gravel, depending on tires. . My gf rides a Trek Madone 3.1, entry level carbon but with rim brakes. She told me that she wants a gravel bikepacking bike. Lightweight, Wider tires, disc brakes, a touring drive train. We're deciding between drop bars and carbon frame or an aluminum frame and flat bars. We're trying to figure out what we need. Carbon frame is preferred but racks and saddlebags are a step into a heavier frame, i.e. aluminium. How light can we pack? Meanwhile, my ExtraWheel trailer probably has the capacity to haul the excess baggage a bikepacking load won't pack. Advice?
This is her first foray off pavement. Thanks for your opinions.

TrackSmart

Some of the arguments in this thread need a scientific control group! There is so much that can alter the perceived ride quality of a bike that has nothing to do with frame material, so comparing completely different bikes doesn't let us isolate frame material differences. SEE BELOW for a Niner RLT 9 Carbon vs Aluminum comparison:

** https://gravelcyclist.com/videos/nin...h-shimano-grx/

This is still a small sample size, but is better than most of the apples-to-oranges-to-coconuts comparisons being made here among different bikes. Our two test riders have two well-designed framesets, with IDENTICAL GEOMETRY, IDENTICAL DRIVETRAINS, IDENTICAL COCKPITS, and IDENTICAL WHEELS. Other than the 1.5 lbs difference in weight between the two framesets, our test riders reported having a very difficult time differentiating between the ride quality of the two bikes when using wide tires at appropriate pressures for gravel riding.

Overall lesson: I agree that companies can design carbon frames with a bit more vibration dampening, while keeping stiffness in the right places, and also keeping them very light compared to metal frames. That said, a rigid frame accounts for a fraction of the overall ride comfort, especially when paired with identical carbon forks and wide tires at low pressures. I give "Steve B." some credit for his Cervelo data link (https://www.cervelo.com/en/ride-quality) which quantifies how much of this compliance comes from the frame on a non-suspension bicycle (hint: an astonishingly small amount). We can all continue to trade anecdotal stories, but at the end of the day the evidence available shows us that rigid framesets (i.e. without suspension) are not the most important component of "ride comfort". It is one of many factors.

[FYI: Thanks for this thread! I'm also looking into my next frameset, since my current gravel/commuting frame was damaged in an accident. It will probably be aluminum for its balance of relatively low cost (compared to carbon) and relatively low weight (compared to steel)]

Lindarets

Just heard Josh Portner of Silca (formerly of Zipp) talking about the Cargo Cult of Stiffness. Interesting listen as always, stiffness comes in at ~54m. Spoiler: it sounds like their testing suggests that flexier -within reason- frames climb faster. Who knew?

Not on the site yet but "Granola and Cargo Cults" is in the feed now.
https://marginalgainspodcast.cc/

mstateglfr 

6'5. A frame with 650mm stack and 405-410mm of reach works great with a 90-100mm stem. These have been what my last 2 gravel bikes were.
The Outback's 596mm stack in the largest size just wouldnt be enough for me to be comfortable for long rides and a lot of wonky compromise, starting with a goofy high angle stem, would need to be used for me.

As for tire clearance, there are just so many great tires that are 40-43mm wide that its a shame to cut the clearance off at 40mm. It eliminates a lot of excellent gravel tires and it isnt necessary. There are plenty of ways to use traditional frame joining(what Ritchey bikes use) and still clear larger tires, especially since the chainstays are 437mm long.

redlude97

this. My caadx and superx with similar geometries and the same wheels ride very similarly. Especially when used with 38mm+ tires at 30psi. I trust cannondale to make aluminum frames with tailored ride quality. Aluminum frames in general nowadays are so good with shaping and tube sizing/butting to mimic carbon layups