Drop Bar MTB Geo

I have an actual epic ht, and it can clear a 40 pretty easily. If you start using a less than optimal chainline, it gets a bit absurd. I can provide evidence that it takes a monster chainring with my 44. Makes an awesome gravel bike.

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Please do, that’s sounds awesome, and would be a great addition to this pool of info.

I’m planning on a 40t myself, however I picked up a set of used GX T-Type cranks. So 55mm chainline. I plan to mitigate this with the 8mm road chainring. Based on Upcountry’s info, I think this will work out.

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I completed my drop bar MTB build this weekend. Rode it for the first time this morning.

The frame is an Airwolf YFM026 (Santa Cruz Highball geometry), combined with the Airwolf rigid fork (480mm A-C). I chose this frame because a bike shop in the Netherlands sells this exact frame as their beach racing bike. So basically, MTB frames with 2.35" slicks for riding on the beach, all specced with 40+ tooth chainrings. I went with a 40t chainring (boost) on mine, but there is clearance for a 42t minimum without changing the chainline!

Here’s an example of this frame with a massive chainring (this is a special chainring with a different offset though).

I chose a Large frame (I’m usually on a Large at 184cm/6ft) and it’s a little on the long side but definitely still fine with a 70mm stem. I’m very happy I looked for bars with a short reach so I could still use a decently long stem.

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That’s awesome! What cranks and chainring do you use?

Epic with drop bars set up…

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What rear cassette are you planning to run? I’m trying to figure out the right cranks to use to get smooth shifting and while I think I understand chainline I’m struggling to put the pieces together. I thought the 55mm chainline was the right fit for the SP-M05/Epic HT, but there don’t seem to be rings larger than 36T to pair with 55mm chainline cranks. I want to run a 9-46 11-speed in the back and a 40T (ideally oval) in front, Shimano GRX shifters and XT derailleur. Any tips?

I’m running a 55mm quarq with an off brand chainring, because almost no one is mounting a 44t mtb ring. Forgive the bad pic, but this drivetrain has about 600 miles on it and it’s going solid.


You’ll need to forgive the flat bars in this thread, but I find that when I ride drop bars too aggressively, they always slip and rotate down, so for something that is sendier than your average gravel bike, I wanted flat bars for it.
If anyone has tricks to keep the bars from rotating while using it like a mountain bike, please enlighten me.

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Aside from carbon grip paste etc, stupid question but are you riding the techy stuff on the drops / do you have your levers set too high / bars angled incorrectly?

If you loosen the bolts on your stem and put your hands in a descending position for the drops the bars and put your weight on the drops, the bars should naturally rotate to the normal position. This means that (like pedals self tightening), drop bars should never want to rotate (because they are already in the position they would rotate TO) when descending.

A common mistake is fitting levers then rotating the bars so that the levers are at the right angle. You should fit bars for the drops, then move the levers to give you control.

The only reason I can forsee ars rotating is if you’re on the hoods and/or the bars are not in the right place to start with.

1 piece bar and stem would fix the issue…

The issue I have is that only helps in a static position. Once you are hitting large compressions or impacts in the drops the loads are at a different angle, and they don’t stay. It is not isolated to a specific bar setup or hood position. It’s been happening to me for years. Once I start pushing 45mm tires to their limit, the bars end up rotating on a big impact or compression. Particularly on steep sections when an impact send more force through the hands than it would on the flat. I try to take most of that force through the feet, but being in the drops brings the body forward and makes it harder to keep all the weight through the feet.

Those are soo expensive though, and are any of them designed for loads that a mountain bike generates?

True. I’ve got a Yoeleo on my gravel bike that was around $350 I think and it’s seen plenty of singe track and done quite a few gravel races without any issues.

seems like an iffy recommendation from you given that the person is already twisting up their conventional bars, but ymmv-yolo lol.

do they make a one-piece bar/stem with the proper stem angle and shorter stem lengths for these hybrids?

Torque? Stem with more contact area? Carbon grip paste?

Yea, shame on me for making a suggestion. :roll_eyes:

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I’ve tried them. Full face plate, torquing bolts in a star pattern with a torque wrench, and re checking them after bringing everything up to torque. Only using 4 bolt stems with short reach bars to keep the leverage lower. Multiple stems and bars. It’s usually racing through singletrack/jeep roads and pushing the pace, as it’s usually a relative strength. I’ve been playing with the mtb for gravel as an idea that might help with this, but I’m not convinced by my experiments yet

no shame intended :slight_smile:

I guess I don’t know what to say then. I’ve ridden cross bikes on mtb tracks for years and people do some pretty hairy stuff on drop bar bikes and don’t have this issue. I really do think that it must be a product of some weird angulation of where your drops are positioned and/or where you’re holding them, but hope you find a solution.

Do you think maybe your hands are moving on the drops and that could be what’s meaning the force changes? If so, some road TOGS are pretty clutch for keeping a constant position and not needing to overgrip.

I’d go so far as to say I wouldn’t ride a drop bar offroad without them now (I have them on my road bike as well).

After some consideration, given the annoying complexities of the MTB transformation, it seems that a custom Ti frame is an excellent choice. Will talk to Mosaic next week.

Fit 44 chainring
Fit 2.4 Tires
Dropbar
Fit Suspension Fork.
Dropper

The only issue is weight. The standard is the Epic S-Works HT frame.

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Custom ti is awesome, but you could get that on an epic.