Drop Bar MTB Geo

It took about ten minutes for the verdict to come in… This is the winning ticket.
I have zero hesitation in saying that this bike is faster over my local gravel/dirt roads than any of the other bikes I’ve owned.

The traction out of the saddle pushing up little pitches at 600 watts is insane. The ability to stay seated and pedal through ruts and over washboard is very easily worth the couple pounds of extra weight. Leaning into loose corners at 20mph feels super stable, and planted. Typically on the standard forest roads on a gravel bike I find myself hopping from the outside line to the apex, and then back to the outside line, and hoping that the middle line isn’t too loose. With the added traction of wider tires and the suspension working, its really reassuring, and lets you push deeper into that corner with more speed. Brain forks get a ton of flak from what I’ve read out there, and this is my first experience on one, so I don’t have a depth of experiences with them, but I do really appreciate that I can just set the “Brain Fade” to one position, and let it do its thing. Same goes for the rear end; as there is obviously no “lockout” but it doesn’t feel needed, even when I was hammering up the paved climb to start my ride. And as a result, there isn’t a need to reach down and change anything after certain sectors of road/gravel/trail. I could see the downsides on a true XC bike, but for this use case, it seems truly ideal. Obviously this is a pretty niche build, and haters will hate, but if you’ve gotten this far in this thread, you’re likely a little more adventurous than most…

10 Likes

I’m right there with you… I was avoiding the suspension fork, and probably got too hung up on “matching” my other bike fits. While the result was totally acceptable, I’m really happy with the bit higher front end, and the extra couple pounds is insignificant.
I’d be way open for something like an 80mm travel fork, but can’t see rushing to change anything on my setup now.

2 Likes

From what I understand, it’s a matter of swapping out the air shaft to a 32mm stanchion 80mm travel shaft. Like 40 bucks retail.

It would afford you more of a 480 AtoC fork length. Even steeper at sag.

I’m curious of your Brain fade settings, I went slightly towards the open side from the middle. And then went like 15% sag.

I think i’ll be trying much more firm and then 25% sag. AKA less pressure.

I’m currently running 75 psi at 170 lbs.

Just some thoughts:

Let me start by saying, I love this build and blurring the lines between gravel and mountainbike. And I see gravel bikes moving more and more into this direction in the coming years.
But you do start to wonder how much of an advantage the drop bars really are on a build like this.

Let’s say you build 2 identical S-works World cup bikes. You build one with drop bars (like this build), the other with standard flat bars with a aggressive position and some bartape in the center of the bars. All the rest is equal.

Let’s compare:

  • On all the fast & straight sections, you can get yourself in a aero position on both bikes (granted, it’s more comfortable when you need to hold this for a long time with drop bars then with flat bars). So the speed on both bikes would be similar.
  • When cornering, the wider flat bars will give more control, so you could argue you’re faster with the flat bars.
  • When going uphill, some riders swear the leverage of the flat bars gives an advantage. I’m not so sure. But you would be less aero then with drop bars, so let’s call it even.
  • When descending. It’s a toss-up between aero and control, so it really depends on how rough the roads/trail is

My point being: “is the best gravel bike just a MTB that is correctly set-up for some fast riding?”

This is ofcourse heavily influenced by the terrain your riding, but where is the cross-over point?
I love that about gravel. There is never one set-up that is best for all gravel riding. There are endless possibility’s to try and find a setup that works for you and your riding.

Thanks for coming to my TED talk

3 Likes

This has been my question as well. Thinking about it, I can see a few scenarios where drop bars would benefit over flat bars:

  1. A lot of straight washboard sections. No need to turn, but want the suspension to smooth out the traction and the ride (I’m guessing that inbound would meet this criterion).
  2. A lot of very tight group riding, where the narrower bars enable you to move around in the bunch without tapping bars (probably important for the pointy end of most races?).

And honestly, that’s all that I can think of.

Personally right now, since I don’t race at the pointy end, I don’t need suspension on a drop bar bike. My rides are either a lot of pavement, or a lot of singletrack. The choice is simpler that way.

Can anybody else identify a specific type of ride where drop bars AND suspension would both be beneficial? Beyond the ones I’ve listed?

1 Like

TL;DR at what point does gravel racing just become glorified XC Marathon racing :sweat_smile:

5 Likes

Depends on the course. Lots of gravel rides near me have everything from pavement to rock gardens, so I’m glad to have big tires and drop bars :grinning:

Plus…it’s an excuse to have more bikes :thinking:

3 Likes

In Norway we have a gravel-event that is classified as MTB (Birkebeinerrittet) and you need to have a flat-bar bike to be able to compete for podiums and to get the “buckle” (which in this case is an asterisk by your name in the results sheet).
In our norwegian bike-forum there is a guy who just have built an optimized bike for this race, and gone the complete opposite of the creations in this thread. I find i do like both the curved bar mtb’s and this flat bar gravel bike quite much. Horses for courses i guess.

3 Likes

I can totally understand the confusion/skepticism/critiques of these bikes. I’ve prefaced it by saying I don’t think everyone needs one of these… As I mentioned, I’ve spent more time on the Epic Evo(any flat bar bike for that matter) in the last three months than I ever have. This was building up towards two “bikepacking” races. The first was mid-May(365 miles, 33k ft vert, 50% singletrack/50%dirt road), and the second is in August(525 miles, 70k ft vert, 75% singletrack). I largely consider myself a “roadie”, and as such, given a choice, I reach for drop bars four or five times a week. It was great to almost be forced to spend some more time on the flat bars of the Epic Evo, as that was the race setup I’ll be using for both races. But with that, there are definitely days where two or three hours in I’m really wishing I had the hand/arm/upper body position that is afforded by drop bars. I run what most would consider pretty slammed/extreme/aggressive on my road bikes, and despite only being 5’10", I’m running a 110 x -17d stem on a Large Epic Evo, with relatively narrow bars by todays standards, at ~730mm. I do have some big ole Cane Creek Bar ends that really do offer a nice perch on longer rides. (also worth mentioning, that for the race in May, I ran some mini-clip on aero bars, and they were essential. I’m honestly debating running them for the second race, despite the ratio of singletrack)

So, with that disclaimer out of the way… Personally, I find drop bars to be more comfortable for pretty much any situation that isn’t singletrack… Living where I do(rural Northern California), I have a 3 mile paved climb up to hundreds of miles of forest roads, with about 50 miles of randomly scattered moto trails. I haven’t loaded a bike into a car/truck for a ride in over three years. So each and every ride has some pavement, and is mostly dirt/gravel roads, with some options for trails. Drop bars make getting to those trails more efficient, and also create a bit of that “underbiking” feel on the trails should I opt for them. But truly I get just as much enjoyment out of sticking to the double track, and so the amount of time I’m “wishing” for wider or flatter bars is really small. I genuinely did consider going with a size Large Epic WC, and building it with a really long and narrow front end, as I have gotten more accustomed with the extra time on the Evo. But I worried there would be way too much similarity, and it seemed a bit ridiculous. I could always have just swapped on the lighter wheelset with narrower tires onto the Epic Evo for the less “trail” focused days, but what fun is there in that.

I am in no way the normal rider, and can fully admit to having the most niche of use cases(250+ mile non-stop races). I’m fortunate that I can justify building a very specific tool for my very specific jobs/races/routes. Suspension has already proven itself as a benefit to me for these races, and I think the melding of drop bars and suspension will be really welcomed.

To sum it up, Yes, I would bet that MOST people would be more comfortable, and as fast if not faster on a well thought out mountain bike for their “gravel rides/races”.

3 Likes

No critique here, I love these kinds of builds that push the envelope a bit. Or that are built for a really specific purpose. Like you have clearly done here.
I guess my comment above (and maybe @wake’s comment as well) comes from a more “traditional” race oriented mindset. Bikepacking and ultra racing are obviously completly different beasts!

For me personally, and the riding I do locally, a gravel bike with suspension doesn’t really make sense, because you’re either on double track or really smooth singletrack that doesn’t warrant suspension. Or you are on singletrack where you just prefer a mountainbike.
The reason I chose a drop bar MTB for my gravel riding is 100% due to my belief that bigger tires are faster for almost all off-road riding, and i wanted tot fit up to 2.35" MTB tires (Thunder Burts at the moment).

This just underlines the fact that there is never one setup that is best. For me, playing around with bike setup is almost as big of a hobby then riding my bike :sweat_smile:

3 Likes

hi crew. I’m in the process of getting the parts to rebuild my hardtail frame into a ‘monstergravel’ or drop bar mtb. I have a Fox 32 SC that I’m considering lowering the travel from 100 to 80mm to get another degree out of the steering- and seatangle. Anyone did this or considered this? Apart form the lower BB is there any other downside to a change like that? Shouldn’t be too drastic of a geo change imho, but maybe I’m missing something?

It’s probably fine. The other impacts (you already mentioned BB) are:

  1. Longer reach
  2. Lower stack (I think each changes by 12-14 mm or so?)
  3. Shorter wheelbase (maybe 10mm? Not sure)
  4. Front wheel is slightly closer to the BB (probably the same distance as the wheelbase shortens), so more likelihood of toe overlap and less ability to run a bottle cage under the downtube.
1 Like

I think I’m gonna build it up with the 100 and see if I have any steerer left when I set the saddle to bar drop and decide then if it’s appropriate to lower the front even more. I’ve ridden this bike for the past 4 years and never had a problem with it’s stack heigth and using a 750mm bar. The flared 400mm bar I have now should in theory make for a more upright position anyway, so I think I’ll be fine in this regard.

I haven’t thought about toe-overlap or the shorter wheelbase. I’ll be running 2.2" Race Kings so not the biggest tires in volume and going with 170mm cranks so even if I lower the front end I think it shouldn’t be an issue. It’s not that drastic of a change I’d assume?

Now I just have to figure out how to fit a 38t chainring on my frame or if I should go 2x… what year is it?

No it’s not a drastic change at all! I don’t have the math handy, but I’d guess it’s less than 10mm.

HI,

I usually use bike-stats.de (don’t worry, it’s in English). It has a handy tool that calculates the new geometry when swapping out components.

bike-stats - Geometry calculator

Just select “install a different fork” at the top. Search your bike or put in your current geometry, and the new fork lenght (shorten by 20mm in your case). And it will calculate/visualize the new geometry.

3 Likes

Depending on your drivetrain system, a wider crankset woth spacers could help. I went dub wide for my 1x12 mechanical XPLR build. And then those ~8mm offset chainrings used for the road/gravel set ups.

I was able to fit a 40t on my size M Epic HT clone.

What frame are you working with? Would love to see your set up!

It’s a 2018 or 19 Trek Procaliber SL

Sorry for the shitty picture…

2 Likes
  • Anywhere you ride reasonably fast (> 17 km/h) and don’t need the leverage and hand position of a wide’ish flatbar. Which would typically anywhere for me except as tricky technical terrain, mostly downhill, too.
    Reason simply is the enormous aerodynamic disadvantage you have on flatbars vs. even just being on the hoods of drop bars.

  • Anywhere else, too, since you simply have more hand positions to choose from. While that is more important for some than for others that’s my main reason.

  • Suspension is always nice since it gives you comfort and cornering grip.

So my question rather would be: why flat bars at all? Well - if you really are doing technical stuff like rock gardens, sketchy downhills, rooty single trails… they come in handy at times. If you are doing really long bike packing events you can combine flat bars with aero bars and then at least you can rest your hands and wrists at times and also get aero. Also there the front suspension helps you that you can ride more surfaces and more securely so with being in those aerobars. That’s my combo for Races like Atlas Mountain Race. While for stuff like Badlands I use a drop bar (but also with Aerobars).

Who doesn’t remember or know the precarious gripping of the fork bridges by pro’s on the grassy finish line straight of some XC races? Or the more common gripping the flatbars right next to the stems. While the latter is somewhat sane and you can also try to make it a bit more comfy by wrapping a bit of tape there (and there a a select few of special shaped flat bars to better facilitate this) in the end it gets uncomfortable soon and you have very little control and no braking in reach what so ever.

Leaving the hands on the grips but just bending down real low helps a bit but it’s also uncomfortable and you still have an aero disadvantage with sticking out elbows and wide shoulder area etc.

Point being: these are all very compromised positions you won’t be in very often and very long while on a drop bar you don’t have to think about this. Even in the most relaxed and in control position you are way more aero from the get go and can become even more aero if you really want to.

Apart from that it’s also a hefty dose of personal preference. I’m super happy that we can build and buy so many capable drop bar builds right now. Or play with those so called alt bars. Because just some flat broomstick of a handle might be the right thing for a fast XCO race or a downhill race but for anything else personal preference and having options prevails.

1 Like

FWIW I’m on my third drop bar HT in the last year, each one having learned from the last to make some improvements.

Started with a M Chisel, then went to a M SWorks Epic HT, now on a custom Mosaic.

For the Mosaic, I sought to replicate my gravel bike fit using stack/reach as reference, while still maintaining the handling performance of a true mountain bike via HTA, offset, front-center, and tire clearance (up to 2.5”). I’ve found the tire sweet spot to be ~2.2-2.3”, with larger tires feeling a little more sluggish and labor some to utilize the side knobs while ripping singletrack. Conti Race King and Maxxis Aspen ST 2.25” are my top two favorite tires with the bike for conditions ranging from fast gravel/pavement to chunky gravel and fire roads, and ripping singletrack. Have raced the DBHT at Migration Gravel, Leadville, Chequamegon, Iceman, and a lot of local gravel and mtb races, so quite the variety with a lot of success. Once getting used to the setup, the only limitations come from the hard tail aspect, not the drop bar. Very capable setup for any mixed surface riding/racing.

8 Likes