I’d be interested, given your experience and perspective - what would you consider to be solid geometry for the drop bar MTB - head angle range and STA range specifically!
Hey Upcountry, it’s been a while with your Epic rig, how has it been for you? Any new changes?
More specifically, how do you feel about the trail figure of your bike? My calculations have me at about 76-80mm… depending on tire size.
With usual gravel trail figures in the 60’s, i’m not sure what kind of handling characteristics to expect. Maybe someone could enlighten me, or share their experiences.
Let me preface what I would consider a solid geometry (for me) with the recommendation that you should choose the geometry (or base MTB frame/bike) according to what you like and what you want to ride with it.
If you like to have fun shredding gnarly downhill trails, doing berms, jumping off tables or find yourself in rock gardens most of the time chances are you prefer a pretty slack bike. Not to say you probably own already a downcountry bike or even a trail bike for exactly this. But then I would also ask: why would you want to consider a dropbar bike, even if it’s a dropbar mountain bike for this kind of riding, at all?
So chances are you want a capable rig to go nearly 100 % off-road and be comfortable and fast at the same time. But you wanna actually ride that thing. As in like: pedal it. Over plains, over easy to more steep climbs and over never ending tailwind driven descends (oh what fun!) and of course also the not so occasional steeper stuff - but within reason. So - you want a good pedalling and a nicely steering bike. Nicely steering on the flat and in slow to medium fast corners. Or very fast corners, but then on fire roads or maybe even tarmac. An allrounder. Not a downhill oriented bike.
This brings you into steering angles of around 70 degrees, give or take and in consideration of all the other parameters. Take into consideration that with suspension you have to look at dynamic or sag-corrected fit. E.g. my Canyon Exceed has a steering angle of 69°. Lower than 70, right? Well, no. With a 100 mm travel fork, set at 25 % sag I’m sitting on around 70.1 degrees. Use this as a handy calculator (Sagged Hardtail Geometry Calculator - MAD SCIENTIST MTB - Bike Geometry Calculators)
When under braking or cornering forces I’ll become even steeper.
I recently tested the new Trek Supercaliber. It has a 67.5 degree steering angle. On paper and when looked at the wheel flop parameter (Compare: 2022 Canyon Bicycles Exceed CF S vs 2023 Trek Bikes Supercaliber SLR 9.8 XT S - Bike Insights) it depends whether you consider this a significant difference or not. But let me tell you: It felt like night and day and the Supercaliber has a very and instantly noticable wheel flop where my Exceed is perfectly neutral (w/o not being unstable or insecure feeling). I didn’t like the new Trek at all. Also not from it’s rear suspension but that’s not the topic here.
So in Summary: I do recommend not going slacker than 69° head angle (can be a bit remedied for newer, slacker bikes specced with a 120 mm fork by using a 100 mm fork with those) and above all: ride the original bike as it comes with the flat bar. If you dig the riding on it you know you’ve found your bike and you can just put drop bars on it (provided there’s nothing super proprietary going on with it which would make it mechanically difficult to put a different stem on it).
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Yea, aero frame. I have a BMC Kaius on 35’s and that thing is fast 
If you’re planning to go narrow on the bars, installing an angleset “backwards” to make the head tube angle steeper is a great way to control the wheel flop without making your seat tube angle even steeper.
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I thought it was that bar ends liked to snag on things. Thats why i dropped them at least.
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Frame: SpCycle M-038 (size S , 778g)
Fork: FK-016 (455mm , 502g)
Groupset: Sensah 1x12
Weight: 8.4kg
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Very nice, you made that fork look very good!
What size of frame do you typically ride? What is your height? Would love to hear about your experience with the fit/stem length.
Thanks!
My height is 170cm, I usually ride a size S bike. This bike has an 80mm/-7degree stem and zero offset seatpost.
Handelbar specs: 380mm/65(!)mm reach/80mm drop (https://a.aliexpress.com/_EIJW9U5)
I feel comfortable, but I want to replace the 80mm stem with 70mm to move the saddle back (now it is pushed forward as much as possible)
I’m also thinking about replacing the fork with this one: (https://a.aliexpress.com/_EJzmLBT)
for a lower landing without loss of tire clearance
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The drop bar mountain bike craze has reached peaked silliness……spotted last night on the streets of Chicago. This is a 25 year old, entry level Schwinn. They sold hundreds of thousands of this model (with a proper flat bar).
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Little update on my Epic HT…
I took a few 8 to 10 minutes KOM’s on a gravel ride lately on my Crux, and I’m eager to give them a go on this, which I’m almost positive will be faster simply as the bigger tires will handle the rough stuff a bit smoother and more efficiently.
As much as I love my Enve SES Aero handlebars, which I’ve got on four bikes, I wanted to play around with something with a bit more flare, and a bit less reach. The Carbon Salsa Cowbell 38cm ticked the boxes, and the external routing is a bit easier to navigate with extreme angles of the hoses, also managed to knock the weight down a bit. 17.78lbs as shown, which is silly…
Really disliked the feel in hand of SRAM levers, and didn’t love the braking either. So, I put together what is taking Shimano a couple years to do… Essentially a 12 speed di2 GRX(albeit without a clutch, but hasn’t been an issue with how good 1x chainrings are these days.) It was fully functional as listed below but I did just toss on an eccentric upper pulley wheel, which allowed me to turn the B limit screw back in a tiny bit. Haven’t ridden it, but I’m imagining it’ll make for a bit quicker/smoother shifting in the small cogs now, while still clearing the big cog out back.
R8170 Di2 12 speed levers and hoses
M8000 XT 2 Piston Calipers
R7150 Di2 105 12 speed rear derailleur
M9100 XTR 12 Speed 10-45 Cassette
M9100 XTR 12 Speed Chain
Sram Force Quarq Dub Wide Crankset w/ Stone 36t Chainring
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Nice set up! And regarding your stem, looks like -17 but what length have you settled on? And what GPS mount is that?
I’ve got a 60 and 70mm UNO stem on the way. Currently playing with an 80mm I had in the drawer.
Just waiting on a heat shrink tubing from Ali to run my cables.
75mm x -25d Zipp Stem, with a FramesAndGear out front mount.
Ok… it’s rideable!
Set everything up, worked through a few incompatibilities but more on that later.
Front lightweight brake rotor gouged my fork posts due to too wide of rivets… replacing the set to another cheap Ali set.
Cable has a bit of resistance probably due to the routing through the bars, lots of bends. Not the end of the world but we’ll see, i’ll probably go external on the right side of the bars only when I rebuild. Left end will stay internal.
Will be rebuilding after a coat of paint. Transparent dark teal gloss over carbon, with some rainbow flake here and there.
Overall, impressed with the geo of this set up! I worried the 60mm would be slightly too long… huh? I’m now at an 80mm! @Upcountry, i’m sorry for doubting you! This is miles longer than my gravel bike’s fit, but feels very appropriate and comfortable. Strange.
I decided to run the front brake hose external, granting me the flexibility to swap to my 100mm SID fork if need be. Not sure i’ll even like that, but want to try it out.
Weight is coming in at 17.6 lbs at the moment! Def happy with that. Ask away if you’ve got questions.
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Hi,
What bars are they? I’m looking to change to some AliX flared bars instead of the normal straight ones. I’m doing a flat 200km MTB/Gravel event in June, which is about 25% singletrack. With the current 40cm bars I don’t feel I always have enough control when it’s reall singletrack.
Thanks
I bet you could fit 2.2 inch tyres on a Revolt. It supports 2.1 inch from the factory (as long as the suspension fork can clear the 2.2, my rigid Revolt form would clear a 2.2 inch tyre)
The Enve SES Aero bars had similar routing to yours shown, and this was part of the reason I wanted to swap to something else… The extreme angle of the front brake hose was further exacerbated by the fact I’ve got a steep stem all the way slammed. Meaning that the hoses have to do a 270 degree bend in like five inches each.
I’m not entirely sure why the longer reach works so well, but as I’ve touched on, it’s got to have something to do with the longer wheelbase/front-center, and getting more weight up front.
Odd that there are no cable ports on the right-hand side of the frameset.
Crossing cables is not very aero, but even if they thought everyone should cross cables, how do they propose you run a dropper?
Also, is that an 11 speed GX rear, or are you running a Ratio Components to make it play with 12 speed?
They are the 3T aerogaia clones. 78 reach, 110 drop. They are fairly straight at where the hoods attach, so that’s nice. Mine are 40cm at the tops too, they flare out to a really wide drops base, I think like 48cm.
Flared bars mess with shifter interface. So I like that these mitigate that
I actually just purchased a “road” pair for my road bike, at 38cm with a very slight flare to be 40 in the drops.