Franken Gravel Ultra Endrance Bike Concept - Will it work?

Objective/Requirements: Create a Franken bike that is suitable for gravel, ultradistance, racing both of the aforementioned disciplines, and bikepacking. Must be able to accept a full range of tire sizes of all gravel up to MTB 1.9/2.1 MTB tires, accept a dropper post, and able to switch between flat or drop bars. Be light of enough to do hike a bike when required. Should be able to provide me the confidence to descend all types of trails that gravel race directors will provide as some directors flirt right on the edge of MTB XC trails. As well as, descend with steep loose over hard or washboard type fire roads . Provide some degree of comfort on extra long rides/all day rides. Must hold the line during a rocky descent.

So here is what I’m thinking initial brain storm: Because my passion is MTB XCM(even though I’m a better road Gran Fondo rider) and because I lack super mad skills and when in doubt I will walk. So I’m thinking of the new Specialized Epic World Cup (SpecWC) frame with double chain ring in front and a 10-52 cassette. I live in an very mountainous area climbs on road range from 1xHC, the rest range from Cat 2-4 climbs and all come with off road version some suitable for car traffic others not so much. Most normal locals ride 30, 32, some use 34tooth chainring. Pros go bigger.
I’m just thinking that a bike with no suspension like standard industry gravel bikes would just be too risky in fast descents, get easily bounced off line in rough stuff. As well as, uncomfortable during ultradistance events.

What do you guys/gals think… :thinking: hmm, not a good idea :man_facepalming:, won’t work or WTF seriously :grimacing: :scream: :confounded:

I’m in the “better solved by two bikes” camp. How will you swap braking between the drop bars and flat bars?


This 100% is the brain buster.

The other question I have is what do you consider to be ultra-distance? 350? 400 miles or more?


Yes, 350+ but 150 will be the starting point…

Valid and fair question…I was initally thinking starting with one type of bar doing a couple of races or serious training events and see how it works out. Then maintain or switch… Its seems most are runing drop bars but can i keep up with industry gravel bikes on an MTB frame drop bars and slightly larger wells?

Salsa Cutthroat all day, and twice on Sundays :star_struck::star_struck::star_struck::star_struck:

Go with a Sram mullet (or they have GRX 2x builds).

  • Easily run 700x45 to 29x2.4 tires
  • Lots of mounting points for gear
  • Dropper routing
  • Can take a 100mm suspension fork
  • Super plush ride with fat tires and rear designed for vibration damping

I’d go with whichever you’re already comfy with, tbh. A nice handlebar and brake+shifter setup isn’t cheap. Also I’d second what @FrankTuna said — the Cutty is a sweet bike.


Pretty sure that Epic World Cup and most every modern spec mountain bike will not take a 2x drivetrain. You would have clearance issues for the crank and it won’t take a front derailleur.


Top tubes on modern mtb frames are too long, to get a proper reach with a drop bar you’ll have to use a stupid short stem, the handling will be rubbish.

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+1 on the Cutty - That’s exactly what you’re describing. It’s a bit heavier than high end race-oriented gravel bikes, but if you want to hold a line on the gnar, that’s a good thing. It’s made for the Tour Divide.

Can be specced either with flat or drop bars, but you’ll have to choose one and just roll with it.


An xc mtb isn’t a terrible option if you want legit full suspension. You’ll want to use short reach drop bars and a short stem. Sram axs makes swapping shifters and gearing easy. No option for 2x though. Besides lack of support for fd on most mtb frames, you can’t run 2x w an eagle mtb cassette (orthe wide range xplr cassettes). If you ride at the pointy end, you may have issues keeping up on 1x on a mtb frame depending on max chainring. I’ve raced a bit of gravel on my spark RC and the max chainring is a 38. That’s workable in most situations even at the pointy end, but it’s definitely on the edge at times (fast tailwind sections).

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Have you looked into eThirteen cassettes (maybe helpful for OP @Junio too)? I know the argument is a 9T cog is not efficient, but you’re basically using that as an overdrive gear when you’re really zooming downhill or with a tailwind. :thinking:

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Yeah, I know about the eThirteen’s with the 9 tooth. It’s definitely an option for folks that want a little more speed. I like to stick with the sram cassettes and I honestly think the risk of being under-geared is greatly exaggerated. While there are places you’d want more gearing, I’ve never been dropped in a gravel races from being under geared. If you are pushing much over 30mph on a flat section, it’s typically not for long. If I was racing with the pros, that might be a different deal, but I find the 38/10 combo good enough for the pointy end as an age-grouper. On my checkpoint, I only run a 42 w/ 10/50 and I could certainly run a bigger ring if I wanted to.

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After thinking about it last night in bed I made and error in distance, sorry.
I’m an American Werewolf in Spain and I have gone native so to speak regarding distance and temperature. So 350 miles is 563 KM and YES that is ultra at this point. As I’m a NOOB at this type of racing.
Once I figure out the bike Franken or industry standard gravel or just use my XC EPIC EVO I have my eye on “Badlands” crowning event here in Spain around 497 miles and 52K ft ascending. But Badlands BADLANDS | BADLANDS 2023
is hard it’s unsupported and is in the only desert here in Europe.

What I dont want is my crowning event on the bike to be my last as it breaks me physically with injury etc. Ergo I’m thinking of suspension and the new Epic WC caught my eye.
There is a race I have my eye on as a tune up the Traka that offers multiple distances and is supported. I would do the 1/2 124miles. That’s kinda my rough draft on planning so far it’s 1-2 years out .

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Sounds good but i’m in Spain and I’m not sure they offer Salsa in Spain. Shipping from the US along with VAT - Value Added Tax 21% is a killer. Now it’s possible that on trip home I pick up the frame and bring it back in the empty bike box flew home with…to try and fool the customs guys…

Do you know if it is possible to mount a 2x on a frame that was designed for a 1x? As I did my initial persual on on bikes and limited all came with 1x ??

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  • Modern full-suspension MTB’s have abandoned front derailleur mounts, almost entirely as a rule. There are probably a few exceptions, but most have ditched them in order to optimize things like frame stiffness, suspension kinematics and such. Short story, 2x + FS MTB are likely a No-Go.

  • At this point, your only real option would be a modern Shimano system (which are still quite rare) or an OLD SRAM one. Not something I think you can really count on in most cases.

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for the brakes go with cable actuated…they’re fine for 95% of anything out there and would solve the swap issue. My road bike doubles as a TT bike and i swap out the cockpit (road to TT bars) in under an hour now with having a full cable housing attached for both options. I use the TRP Spyres but have used the Sram BB7’s and the Yokota/juin-techs and the Tektros (worse by far). Many Mechanics get real snobby about them but they can be lighter (depending on combo), way easier to adjust (on the fly if it gets muddy) and in some cases better breaking (I had a set of BB7’s that were so good it snapped the rear seat stay of my CX rig).
The only downfall from a performance standpoint is their modulation but really you get used to it after a ride or two and learn how to modulate and stopping power is very similar and if not enough, bumping up a rotor size solves it. The only thing to watch out for is fitment. They tend to take up more space in the rear triangle and don’t fit some frames (particular if its a SM). Biggest win is no more brake bleeding! Have tried the hybrid cable/hydros and really was not impressed, braking power was the same, they are crazy heavy and take up a lot of space on the bike (rear triangle fitment and even are so wide they rub spokes)…good luck with your build and keep us updated with pics and specs!


There are a few distributors in Europe. As a clueless American I’m not sure it this is helpful but wanted to mention it!

Best of luck on the riding though. Badlands sounds absolutely epic :exploding_head::exploding_head::exploding_head::exploding_head:

yeah that is my worry… as there is a bunch of climbing and then if I fix the climbing issue with a one by I can’t hang on the road with gravel guys…
It’s kinda like Chris Blevins at a gravel race last year he rode his Epic and was good on single track and off road climbs but when things flatten out he could not hang on the pointy end. Now I’m not ever going to be at the pointy end more like the tail end but if I have the opportunity to draft on some road miles it would be nice. but it doesn’t look like i’m goint to get there on MTB frame

Get one of these to swap between flat and “drop” bars :joy:

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