Direction of gravel bikes

With riders pushing for more tire clearance how long till we have boost?

To run the 50mm tires you see bike company’s limit front crank options. A lot of people are running 1x with a 50 front a mullet in the back. If we have more spacing in the back would that allow sram to add a 14th gear allowing for smaller jumps?

I haven’t followed the gravel progression closely, but prior to hub expansion to Boost, I’d expect the shift to a MTB bottom bracket & cranks setup to be potentially more beneficial.

  • Old school consideration of the 68mm Road (and gravel) setup vs the 73mm MTB would help with chainstay clearance, which is a limiter to a degree, even with stuff like dropped stays.
  • Not sure what everyone of them is doing with the various BB standards these days, but I’d start looking there before pushing to a Boost that has less actual benefit IMO. And of course committing to 1x would be part of that transition.

Spoiler alert on the 2030 Specialize Diverge…

I kid of course. It would have cowchipper bars

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I welcome everyone riding drop bar MTBs. I love my Cutthroat :rofl::star_struck:

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Thought it would be easier to do boost from a fit perspective since q would get weird

Don’t SRAM Wide cranks basically already do this?

I’m skeptical we’ll see boost anytime soon, as I think there would be substantial backlash against a new standard. And boost is pretty half-assed in terms of the “benefits” it provides, it’s only 6mm wider in the back. Some MTBs use “super boost” spacing, though this is also polarizing on the MTB side. No one likes new standards that make all current wheel sets obsolete…

I also don’t think this is really needed. I think with tricks like dropped chain stays and/or solid carbon layups (as Lauf uses) you can make a frame that can accommodate 50+ mm tires. 50mm tires with 2x shifting may be limiting, but there I think altered FD designs would be a potential fix.

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If you only do Boost rear, I am not sure it’s possible to shift the chainring out wide enough on a “road” crank to maintain a proper chainline for 1x setup.

  • They might. That’s why I left it open ended in my comment and am happy to hear more specifics from those who know better.

The new MOG shows-what your options are. Even wide cranks limit tire size to 45 if you want 2x. I was thinking the boost would maybe allow them to jam a 14th gear on the back.

https://support.enve.com/hc/en-us/articles/13067260280091-MOG-Chassis-FAQ#:~:text=Cranks%20are%20offered%20with%2038,for%20a%20direct-mount%20ring.

Seems like a perfect use case for Classified Powershift.

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Yeah. Maybe that’s where it’s going. SRAM needs to
Buy them.

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People have been saying that about SRAM for a while, but it hasn’t happened. I wonder if they have their own system or if PS is asking way too much.

Doesnt the lauf seigla use a 73mm sram road crankset. I know ive seen mtb tires and 48tooth chainring on one before

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Yes.

My latest gravel frame uses Boost cranks and a SuperBoost rear hub to improve the chain line. This means it’s trivial to run 29 x 2.2 Race Kings. It’s 1X mostly but I don’t want to deal with front derailleurs any more. The cranks are wider MTB cranks of course, but my hips hate low Q road cranks anyway so this saves me from have to figure out how to widen my pedal stance.

On a earlier frame I did something similar but with a 142 rear hub offset 6mm to get a similar chain line and a dishless rear wheel with more normal hubs. But since then I migrated all my mountain bike frames to SuperBoost so I had wheels kicking around.

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Can you share which MTB frames you’re riding?
I was under the impression that mostly enduro and downhill frames used SuperBoost - that there weren’t really any trail or XC frames that used that spacing…?

They’re all custom so I run whatever I want. The 3mm boost of Boost didn’t seem worth changing for but SuperBoost actually gave some real room to work with.

I love my cutty too, but mine (1st gen) is very limited on chainring size. Ie i can get dropped on paved pedalling downhills

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It wouldn’t be my first choice for racing since it maxes out at 40T. I’ve been running a 38T ring, so 38x10 gets me to ~30 MPH at 90 RPM on 700x48 tires, which has worked well enough for the riding I do.

This is very similar to what I run on my Lauf. I’m biased… but my guess is that more gravel bikes will shift in the direction Lauf has set.

The 10-52 paired up with a 46T on the front provides some wicked speed for most days. Then chuck the 40T for more ‘adventure’ style rides.

Also 50mm conti race kings… what a party of a bike :tada:

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