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  1. #1
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    What is an advantage of cyclocross/gravel bike over a rigid mountain bike?

    I recently spend many hours researching wheels and tires for my mountain bike. This may be not big news for many of you but I was blown away by research done on off road rolling resistance. Apparently, wider is better.

    Tyre pressure, tyre diameter, tyre width, tyre construction, tyre tread and other factors all have an effect on rolling resistance.

    On a completely smooth surface the following applies: The higher the inflation pressure, the inferior the tyre deformation and thus rolling resistance.

    Off road it is exactly the reverse: The lower the inflation pressure, the lower the rolling resistance. This applies equally on hard gravel roads and soft forest tracks. Explanation: A tyre with low inflation pressure can adapt better to a rugged surface. It sinks into the ground less and the whole rotational mass is held back much less by the uneven surface.

    Tyres with a smaller diameter have a higher rolling resistance with the same inflation pressure, because tyre deformation is proportionally greater. The tyre is flattened more and is ďless roundĒ.

    Wider tyres roll better than narrower tyres. This statement generally invokes skepticism, nevertheless, with tyres at the same pressure a narrower tyre deflects more and so deforms more.

    Obviously, tyre construction also has an effect on rolling resistance. By using less material, less material can be deformed. And the more flexible the material is, such as the rubber compound, the less energy is lost through deformation.

    Generally, smooth treads roll better than coarse treads. Tall lugs and wide gaps usually have a detrimental effect on rolling resistance.
    I was contemplating getting a gravel bike for some dirt roads and canal paths around Phoenix area. At this point I wonder if would be better just to use one of my mountain bikes. There aren't huge saving in weight and wheels (without spending big bucks) I suppose going rigid and smoother tires would be in order. Maybe the dropbars would be nice for aero riding and more hold positions.

    Main point is that skinny wheels/tires are actually an disadvantage on dirt in terms of rolling resistance, traction, braking and cornering.

  2. #2
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    Quote Originally Posted by metalaficionado View Post
    I recently spend many hours researching wheels and tires for my mountain bike. This may be not big news for many of you but I was blown away by research done on off road rolling resistance.
    It's not specific to off-road. Even on decent asphalt, it's possible to pump a tire too stiff, such that transmission of road buzz through the bike+rider wastes rolling energy and reduces performance. That's a big part of why the pro peloton has trended to wider tires over the past decade.

    Maybe the dropbars would be nice for aero riding and more hold positions.
    That's the big thing. It takes effort to maintain a powerful+aero posture with a typical mountain bike fit. It's totally possible to do gravel rides on an MTB, but it's usually not the most optimal machine, unless the "gravel" ride is weirdly technical.

  3. #3
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    Narrower crank q-factor might be more efficient to some riders. Their wheels generally have less drag since their hub bearings and axles are smaller. They have more drivetrain efficiency due to their bigger chainring. The increased challenge of riding CX can make the ride feel more fulfilling.

    HTupolev mentioned posture/positioning, which is a big one too.
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    drop bars on modern mtbís is no bueno

    geometry issues, shifting cost/issues, brake issues... can all be overcome but by then you may as well get a gravel/cx bike

    Iíve ridden and own both. Most of the time for gravel rides I grab the cx bike. Itís faster by a lot for most of what youíre talking about. However, on super rough roads and/or super long stuff with rough sections (hillybilly roubaix type racing) I prefer the ht mtb.

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    Dropbars on a MTB works very well. Just make sure you measure everything carefully (very carefully) to get a proper fit.

    I used my road bike as a reference (which fits me perfectly) and matched it up with my monstercross setup. I have done several 65+ mile gravel rides on it and it's very comfy!

    The biggest issue was the front end and fork selection. Axle to crown was a key measurement. I tried to match the AC of the original suspension fork because I didn't want to alter head tube and seat tube angles too much. I'm very pleased with the outcome.

    The bike has clearance for all kinds of tires! Currently running 40mm gravel kings and it has room for much bigger. I like having so many tire options.

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    Quote Originally Posted by wjphillips View Post
    Dropbars on a MTB works very well. Just make sure you measure everything carefully (very carefully) to get a proper fit.
    It CAN work very well. However, like I said there is a LOT to consider since most drop bar stuff is not directly compatible with MTB stuff. It just depends on budget and what you are willing to give up.

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    We're all on the same ship, and it's sinking.

  8. #8
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    Thanks for the replies. They make gravel/CX frames that allow up to 45cc tires. That would probably the most ideal to run dropbars with widest rims/tires possible.

    Something like this. DonnyBrook - OX Platinum All-Road

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    If youíre really wanting wide there is this https://salsacycles.com/bikes/fargo/...go_ti_frameset

    or a bit more traditional but still mtb wide https://salsacycles.com/bikes/cutthr...throat_force_1

    or closer to cx/gravel but still plenty of clearance
    https://salsacycles.com/bikes/warbir...carbon_ultegra

  11. #11
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    Quote Originally Posted by khardrunner14 View Post
    drop bars on modern mtbís is no bueno

    geometry issues, shifting cost/issues, brake issues... can all be overcome but by then you may as well get a gravel/cx bike

    Iíve ridden and own both. Most of the time for gravel rides I grab the cx bike. Itís faster by a lot for most of what youíre talking about. However, on super rough roads and/or super long stuff with rough sections (hillybilly roubaix type racing) I prefer the ht mtb.
    This. By the time you convert to drop bars with a more efficient drivetrain, might as well get a cx bike that's already meant to do that.

  12. #12
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    that Fargo Ti is beautiful... but that price !

  13. #13
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    Quote Originally Posted by matadorCE View Post
    This. By the time you convert to drop bars with a more efficient drivetrain, might as well get a cx bike that's already meant to do that.
    Thatís my point :-)

  14. #14
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    Are there any mtb HT frames that allow big chainrings? Could be a start to begin to compare CX vs rigid.
    We're all on the same ship, and it's sinking.

  15. #15
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    Quote Originally Posted by Varaxis View Post
    Are there any mtb HT frames that allow big chainrings? Could be a start to begin to compare CX vs rigid.
    define"big".
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  16. #16
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    SRAM CX1 chainrings come in 38t to 46t.

    SRAM Eagle chainrings come in 30t to 38t.

    Having trouble finding any that allow more than 36t. Open One+, Air9 RDO, SIR 9...

    Andy Blair said he's going to race 38t on his Epic HT: ¬Ľ Bike Check: 7.8kg Specialized S-Works Epic Hardtail

    Quote Originally Posted by Andy Blair
    The bike came stock with a 34t chain ring but I will race on a 38t. Thatís the beauty of the huge range of SRAM Eagle, a 38 will give me a smaller gear than using a 32 on XX1 (which was as small as I ever rode) but a taller gear at the other end that can be nice on fireroad sections on marathons, especially if there is a tailwind and you need to put someone under pressure.
    We're all on the same ship, and it's sinking.

  17. #17
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    Quote Originally Posted by matadorCE View Post
    This. By the time you convert to drop bars with a more efficient drivetrain, might as well get a cx bike that's already meant to do that.
    Unless you have most of the parts already. For my build I had everything sitting around my garage. I guess being a hoarder has its advantages

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  18. #18
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    As a road-bike geometry enthusiast (because they're more comfortable) I think gravel bikes are better in every respect except one - and unfortunately it's a big exception - and that is they use skinnier higher pressure tires. Not only are the tires skinny and higher pressure, but they are also just as heavy and often heavier than 2.1" tubeless Schwalbes. Also the road-style rims are heavier because they have to be sturdier with small high pressure tires. They won't work as well tubeless either which is significant issue in places where you expect to get punctures on almost every ride, as in the Southwest. Bikes should be designed around the best tire for an application - the tire with the best weight, grip, and tubeless ability. Slightly-bigger-than-a-cx tire doesn't cut it, that's an idiotic, nonsensical design consideration.

    I built up a drop-bar vintage mtb bike with 2.1 tubeless tires which I love although the steel frame is very heavy.

  19. #19
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    The Timber Spork

    The Timber Spork works really well everywhere I've tried it. Converted to drop bar 29er mountain bike with remote lock out Lefty - something of a greater Slate.

    Apologies for the upside down photo - this site doesn't play nice with Apple productsWhat is an advantage of cyclocross/gravel bike over a rigid mountain bike?-img_9890.jpg
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    I also really like my converted kona mtb. The main hassle I had with it was finding a way of using a triple chain ring with brifters. Other than that very easy conversion. Whether you'd be better buying a proper gravel bike depends almost entirely on how much cash you've got to spare and what parts you have lying around.

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    I have been debating the same thing: add a rigid fork and smoother tires to a MTB or buy a CX/Gravel bike.

  22. #22
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    FIFY

    What is an advantage of cyclocross/gravel bike over a rigid mountain bike?-img_9890.jpg
    What a perfect waste of time

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    Thinking about the same thing. Buying a hardtail with boost wheels and rigid fork, which I can change to a suspension fork whenever I need it. Or maybe just go directly for a gravel with enough clearance for 48/50 tyres...

    How thin can be my tyres if I have 23-25 inner rims?

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  24. #24
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    I prefer my modified hardtail mtb for gravel purely because of the ability to run 2.35" Schwalbe big Apples. They seem to me to be a good allround tyre that doesn't hold you back on the road and is ok on most offroad surfaces if the pressure is low enough for the tyre to conform to the surface.

    What I like about CX bikes is their more horizontal toptubes which are more comfortable when you shoulder the bike.
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  25. #25
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    Quote Originally Posted by j102 View Post
    I have been debating the same thing: add a rigid fork and smoother tires to a MTB or buy a CX/Gravel bike.
    Itís been a couple of months since I posted that. Iím putting money aside to buy a CX/Gravel bike.

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    The main advantage of a gravel bike is the frame geometry if you prefer a road bike riding position with drop bars. Mountain bikes have waaaaay too long top tubes to use with drop bars. Consider that mtb handlebars sweep 50mm or more backwards from the stem while road-style drop bars sweep forward about 80mm from the stem. That means you can only use mtb or road handlebars on bikes specifically designed for those handlebars. They're not interchangeable. People try to do it but it doesn't generally work very well.

    One advantage of mtbs over gravel bikes, aside from their better lower-pressure tires which work better tubeless, is their rims can weigh less because they aren't required to be as strong for tires with more cushion. Smaller higher pressure tires require stronger rims which weigh more. There's no weight or performance advantage to skinny 40mm tires on a gravel bike unless you're going to be riding on pavement a lot.

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    Quote Originally Posted by esXso View Post
    One advantage of mtbs over gravel bikes, aside from their better lower-pressure tires which work better tubeless, is their rims can weigh less because they aren't required to be as strong for tires with more cushion. Smaller higher pressure tires require stronger rims which weigh more. There's no weight or performance advantage to skinny 40mm tires on a gravel bike unless you're going to be riding on pavement a lot.
    My strong tubeless gravel rims weigh 440f/450r. They are also much more aero than a MTB rim which makes more of a difference than mere weight at higher speeds.

    There certainly is a weight and performance advantage to skinny tires off road, especially on mixed surface rides.

    My experience is quite different than what you have claimed.

  28. #28
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    Quote Originally Posted by bloodypalms View Post
    My strong tubeless gravel rims weigh 440f/450r. They are also much more aero than a MTB rim which makes more of a difference than mere weight at higher speeds.

    There certainly is a weight and performance advantage to skinny tires off road, especially on mixed surface rides.

    My experience is quite different than what you have claimed.



    Yep, one look at the bikes of the Trans Iowa or other gravel races proves out that a gravel bike is the best choice for gravel. Imagine that.
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    Quote Originally Posted by bloodypalms View Post
    My strong tubeless gravel rims weigh 440f/450r. They are also much more aero than a MTB rim which makes more of a difference than mere weight at higher speeds.

    There certainly is a weight and performance advantage to skinny tires off road, especially on mixed surface rides.

    My experience is quite different than what you have claimed.
    Actually, the bigger the rim for the same tyre width, the more aero the tyre shape becomes, even if it doesn't seem logic. The problem is that there is a maximum that you can fit within safety standards .
    http://engineerstalk.mavic.com/en/th...ght-rim-width/
    Also you can find mtb xc rims of 265grms, so the weigth penalty is not small if you will not go through fast gravel roads that benefit from high pressures.

    It basically depends on the gravel road that you are going to go through. The wheel combo choice is not a small thing to consider

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    Quote Originally Posted by life behind bars View Post
    Yep, one look at the bikes of the Trans Iowa or other gravel races proves out that a gravel bike is the best choice for gravel...
    Ah, racing. I fear its effect on the infant gravel bike.

    If racing comes to dominate the scene, we'll get gravel bikes optimised for the speeds and the way elite 0.1% can ride them, eg a bike with the silhouette of a CX bike with a bottle cage, a low riding position, but slightly wider tyres.

    What I want is a comfortable all day bike competent on rough surfaces with no compromises to the fast set. If I get into a situation where aero positions and equipment would enable me to go a tiny bit faster, it's because there's a tailwind or a long downhill.

    Such a bike need not be "slow", just optimised for the speeds most of us travel at rather than for the very few really fast people. For comparison I'd like a silhouette similar to the bikes that were ridden offroad in Europe in the postwar period. Still with dropbars, but with them mounted on a frame with a higher stack, but of course with much wider tyres.

    Unfortunately for me, "fast" sells bikes, especially to those who don't realise it's the condition of the engine, not the bike, that is most important. The real racers can ride old rattletraps and still leave us in their dust.
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  31. #31
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    I ride geared and single speed MTB's everywhere and often do fast pace (15-16 mph average over 2-3 hours) urban assault rides.

    Recently picked up a Soma Wolverine CX/gravel bike to click off the 35+ mile round trip bike commute faster than on an MTB. It has TLR rims and I setup 1.8" small knobbies on it that can be inflated up to 60 psi. I have no trouble churning at a 20+ mph pace on this setup...
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    Quote Originally Posted by srmanuel View Post
    Actually, the bigger the rim for the same tyre width, the more aero the tyre shape becomes, even if it doesn't seem logic.
    My aerodynamic comment related to rim shape.

  33. #33
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    I just bought/built a 3T Exploro, billed as an aero go anywhere bike. Optimized for 20mph. (https://www.3t.bike/en/3t-bikes/new-...tmount-20.html)

    Bought it after trying to gravel mod my Epic HT, for a few reasons. The HT (I put 45mm tires on) riding position wasnít comfortable on a 50 mile ride where it was 50% flat gravel/tarmac. With the Exploro I can put 700x23 as well as 650b and up to 2.1 mtb tires...currently have 650bx47mm on there. I can load it up with travel bags or svelt it down to a 16 lb road racer. Currently building a second wheelset to do that for when I want to tag along with my roadie buds. It suits the kind of riding I like these days: longer mixed surface.



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    There is a lot of talk about aerodynamics here and elsewhere, but I'm guessing none of you have any data on the matter other than generalizations from the internet. I see tons of people on gravel and cx bikes that are more upright than my position on my rigid xc hardtail. Presumably, based on our assumptions on aerodynamics, my hardtail should be better. Add a frame bag and a crosswind, and any bike will be terrible. Also, there are many options for increasing hand positions on a hardtail. Bar ends, inner bar ends, Jones bars, etc. I'm more comfortable on flat bars than drop bars, and I can use grips that absorb more shock than bar tape on drop bars, even double wrapped. For the record, I am equal parts roadie and mtber, so I'm not speaking from a mtb bias. I have spent much more time on road bikes over the years than mtbs.

    Many areas of the country have steep, rough descents that are much more comfortable on a hardtail. Someone mentioned Hilly Billy Roubaix. I've done this race on a mtb, and often the winner is on a mtb. When you are crawling up the climbs, aerodynamics do not play any role, but on the rough descents, the control of a hardtail is very helpful.

    Lastly, in areas like KS and OK where the mud is beyond sticky, the extra clearance on a hardtail is a major advantage.

    Oh, and there are plenty of people that do well in races on a hardtail. Andrea Wilson won her age group at DK, and was third overall in the women's category. Pretty sure she was able to keep up with tons of people on gravel and cx bikes. All of this is to say that the advantages of a gravel bike are not as clear as people claim. I have no problem with people buying and riding gravel bikes. I also like them. I just think they are too often touted as being faster, more efficient, etc. than a hardtail, and I'm not convinced that is true. All the youtube comparisons I see are worthless too because they compare hardtails with a suspension fork, 780mm bars, and mtb tires to gravel/cx bikes with narrower tires designed for the terrain being ridden. It's an unfair comparison.

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    Quote Originally Posted by jmal View Post
    There is a lot of talk about aerodynamics here and elsewhere, but I'm guessing none of you have any data on the matter other than generalizations from the internet.
    Bad guess.

    ďMy strong tubeless gravel rims weigh 440f/450r. They are also much more aero than a MTB rim which makes more of a difference than mere weight at higher speeds.Ē

    https://enve.com/journal/reducing-tr...s-the-ses-4-5/

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    That is one component viewed in isolation. It was not tested on your bike, with you pedaling the bike. If you have a gravel bike with those rims, but your position on the bike is less aero than mine, it's irrelevant. I'm speaking of systems and riders, not a single component. Nobody on the forum has been in a wind tunnel with their bike, in their riding position. People make broad statements about such and such a bike being more aero than a hardtail, but my point is that there are a multitude of factors that affect aerodynamics, so it is not possible to make such claims based on a component mfg's claims on the internet. Simply buying a "more aero" bike, does not guarantee that you are more aero than the next guy, regardless of the type of bike.

  37. #37
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    Quote Originally Posted by jmal View Post
    That is one component viewed in isolation.
    So?

    You guessed ďnone of you have any data on the matter other than generalizations from the internet.Ē

    I do have data, provided above.

    Again, a bad guess on your part.

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    You are ignoring the larger context of the discussion, i.e. people saying a gravel bike is faster than a hardtail because it is more aero. This is a common claim, and my contention is that the people making the claim have no data. If you think being a pedant, and isolating one variable counters my claim, enjoy your victory.

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    Says the guy with no data. Awesome.

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    Gravel bikes are optimized for the application of riding gravel. You can also optimize a cyclocross, road or mountain bike for gravel if you choose. To get back to the question, you can buy a gravel bike that's made for riding on gravel. You can also take a different style of bike frame and use components you have and make a bike that's likely equally suited to riding gravel.

    Individual choices (wheels, tires, geometry, aerodynamics, handlebars) would relate more to your budget, application and location. Where I live we don't have much gravel and the gravel we do have is pretty manicured to where I can usually ride my road bike on much of it and it's faster than any other bike (you can argue the reasons.) That being said my 29er hardtail and cyclocross bike seemed to roll about the same speed but the cross bike was more comfortable and easier for longer rides that include pavement while my mountain bike was better at mountain biking.

    I now have a steel gravel bike that I use for commuting, winter, rain, gravel, bike paths, bar-hopping etc. that I can put away wet and abuse and I save the mountain bike for mountain bike rides. It's more than just a bike for riding gravel, it's my alternate transportation as well.
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  41. #41
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    One thing to consider:

    If someone has an upright position on a gravel bike, they probably have a similarly upright position on an MTB. So thatís probably a wash.

    Just looking at an MTB and a gravel bike from the front, itís pretty easy to see that the gravel bike has a lower cross sectional area. Less drag.


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    Quote Originally Posted by Le Duke View Post
    One thing to consider:

    If someone has an upright position on a gravel bike, they probably have a similarly upright position on an MTB. So thatís probably a wash.

    Just looking at an MTB and a gravel bike from the front, itís pretty easy to see that the gravel bike has a lower cross sectional area. Less drag.


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    Re: position, this might be true. I still contend that most of the gravel bikes I see in the wild look more like they were set up by someone that rides trail bikes rather than road bikes. And, even though the frontal cross section may be narrower, it's insignificant compared to the sail created by an upright position. I guess my issue is that people broadly claim aero benefits, but most non-elites that I see are negating any aero benefits with their position. I will also assume that these people are rarely traveling fast enough for slight aero advantages to matter much. If someone is new enough that they are asking about the advantage of a gravel bike vs a mtb, they are likely not riding in an aero position at speeds where it matters. Just an assumption, I know.

  43. #43
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    Quote Originally Posted by GT Fatty View Post
    amics, handlebars) my 29er hardtail and cyclocross bike seemed to roll about the same speed but the cross bike was more comfortable and easier for longer rides that include pavement while my mountain bike was better at mountain biking.
    +1. My situation and reasons for building a gravel ride exactly.
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    Unless you constantly ride with zero wind, the aero factor does play into it specially in open areas of trail.

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    Having lived in Kansas with plenty of wind, I can say that my hardtail is no slower than the cross bike I used to use on gravel. Aerodynamics are important to a point, but the difference between my two bikes was not noticeable at all. My problem, once again, is with the notion that buying a gravel bike instantly makes you more aero. This simply isn't true. I think tires have a much bigger impact on speed.

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    Tires, gears, comfort for longer rides and weight are the main differences. IMHO.

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    Quote Originally Posted by j102 View Post
    Tires, gears, comfort for longer rides and weight are the main differences. IMHO.
    In my case, weight is a wash, I ride the same tires others ride on gravel bikes, and I find hardtail just as comfortable. What in particular do you like better about the gears on a gravel bike? For example, I hate 1x on anything but MTB, and depending on terrain I don't always prefer it there. A 2x mtb has a great range for gravel. A 38x11 is plenty fast and with a tighter cassette has nice gaps between gears unlike 1x.

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    Quote Originally Posted by jmal View Post
    In my case, weight is a wash, I ride the same tires others ride on gravel bikes, and I find hardtail just as comfortable. What in particular do you like better about the gears on a gravel bike? For example, I hate 1x on anything but MTB, and depending on terrain I don't always prefer it there. A 2x mtb has a great range for gravel. A 38x11 is plenty fast and with a tighter cassette has nice gaps between gears unlike 1x.
    For Gravel/CX I like the 46/36T or 48/34T with a 11-32 cassette. And I still believe they are more comfortable on longer rides.

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    Quote Originally Posted by j102 View Post
    For Gravel/CX I like the 46/36T or 48/34T with a 11-32 cassette. And I still believe they are more comfortable on longer rides.
    I think for a lot of the country that gearing is good. However, there are places where it is a little tall for the terrain. Some of the roads in VA are steep enough that I would have difficulty making the climbs with that gearing. Conversely, in the Midwest, I don't think the 46 or 48 is necessary, though it does keep you in the middle of the cassette, so there is that.

    I should also reiterate that I like gravel bikes and think they are a great direction for the market. I just think it is worth pointing out that not all the claims are true, or at least they are not as significant as people make them out to be. Many people can ride and race hardtails that they already own and be fine.

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    Quote Originally Posted by jmal View Post
    Having lived in Kansas with plenty of wind, I can say that my hardtail is no slower than the cross bike I used to use on gravel. Aerodynamics are important to a point, but the difference between my two bikes was not noticeable at all. My problem, once again, is with the notion that buying a gravel bike instantly makes you more aero. This simply isn't true. I think tires have a much bigger impact on speed.
    It won't instantly make you more aero, but having the ability to tuck in under high head and cross winds is a noticeable difference between a flat bars vs drop bars.

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    Quote Originally Posted by matadorCE View Post
    It won't instantly make you more aero, but having the ability to tuck in under high head and cross winds is a noticeable difference between a flat bars vs drop bars.
    Even on commutes in my town, the headwinds are bad enough at times that I will not ride a flat bar bike unless the snow warrants it. I imagine that some of the long stretches of gravel in the Midwest are just as bad, if not worse; and without a peloton to protect you, the ability to lower your frontal profile becomes very important...
    Salsa Timberjack SS
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    Quote Originally Posted by matadorCE View Post
    It won't instantly make you more aero, but having the ability to tuck in under high head and cross winds is a noticeable difference between a flat bars vs drop bars.
    People who don't understand this probably have never lived in a place where there are significant winds (or are so strong they don't notice ).

    I prefer an upright riding position, but on bikes that are going to see significant road mileage or be ridden in open country, I fit dropbars. The difference between riding upright and getting down on the drops is quite significant.

    A CX bike is designed around a dropbar, so no compromises have to be made to fit one, whereas on an mtb, fitting a dropbar can become quite involved because of reach and stack issues.

    On the other hand an mtb fits wider tyres, and that makes a huge difference to comfort and control on rough tracks, especially if you are on a long ride. Also they stop a lot better.

    Take the best characteristics of the two of them, and you have the perfect gravel bike.
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    Quote Originally Posted by edubfromktown View Post
    I ride geared and single speed MTB's everywhere and often do fast pace (15-16 mph average over 2-3 hours) urban assault rides.

    Recently picked up a Soma Wolverine CX/gravel bike to click off the 35+ mile round trip bike commute faster than on an MTB. It has TLR rims and I setup 1.8" small knobbies on it that can be inflated up to 60 psi. I have no trouble churning at a 20+ mph pace on this setup...
    This. I love my Wolverine! I have 700x42 Resolutes on mine - mini knobs for hook up, and high ridge in the center for pavement. Low and long geo for long rides and plenty of room for stretching out. Smooth steel to absorb road/trail chatter. And I spec'd to my own fancy for less than a lot of comparable bikes would have cost as a complete.

    But to me, the difference between a gravel and rigid/hardtail MTB is geometry and riding position. Shorter top tube for drop bars, longer stem, and more weight over the front wheel. Steeper headtube for more nimble handling, lower headtube for more aggressive riding position, lower bottom bracket for stability, higher top tube, and reduced tire clearance to fit just what is needed and nothing more. It is much easier to get aero on a gravel bike with drops than a suspension ready/equipped bike with flat bars.


    Someone above mentioned smaller axles for smaller bearings for less resistance, but that isn't the case. Smaller axle and smaller bearings make more resistance. But, smaller 12mm front axle for road/gravel because less weight and less need for the stiffness provided by 15mm axles. Rear axle is the same 12mm.

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