One data point from the Silca tire pressure calculator:
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That chart from Silca is probably pretty close to what most people should follow, but there are a lot of factors that determine what’s optimal for any one person given their unique proportions and the conditions they’re riding in.
The geometry of the bike should make the most difference though rather than bike fit. I see often people moving their saddles forward to weight the front end and in my opinion, the better way to do that is to find a bike with a shorter FC (smaller frame) and use a longer stem if that’s the goal.
I think that fit has a lot to do with the intent of the rider. Yes, your body needs to fit between all the contact points well, and this is ultimately anchored to the BB, but the weighting of the wheels through the balance of FC and stem length based on terrain should be a big consideration.
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Not to pick on you @mcneese.chad , since you have so much experience.
But a 1 percent difference in front/rear weight distribution is 2 pounds - for a 175 pound rider.
That’s the weight of 32 ounces of water. Granted, when we’re talking about weight distribution, we mean the front and rear of the wheelbase (not next to the BB where many bottles are carried). But still, that seems like a very minor change in the grand scheme of things.
Do we have a sense of whether or not just changing the F/R distribution changes how the bike handles?
F/R weight distribution is all about bike handling. In some scenarios, more weight on the front tire is beneficial. In others, it can make things a lot more sketchy…
Again, this has nothing to do with bike fit. You can have the exact same fit on two different bikes with different COG and weight distribution on each…
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TL;DR: Yes… changing weight distribution can certainly matter, at least to some riders.
Without rehashing my gravel journey in detail here, I went from a Trek Boone CX on skinny 32’s and road-like WD, to the Salsa Warbird with 40’s plus more MTB style WD and hated it. I mean I really HATED how that bike handled. It tossed me to the ground not once, but THREE times due to the long front center and slack head tube angle and washouts at high speed in flat & loose corners. The same type of stuff I had ridden on the Boone with no problems despite being on worse tires and the wrong geometry for “gravel” racing. I never measured the actual weight distribution, but the delta in the geo is pretty clear that the two have very different loading on the tires.
Using that bad experience and comparing to my great experience on the Boone, I ended up on an All-City Cosmic Stallion Ti that has a geometry more in line with the Boone (aka roadie style) that I much prefer. I have proper weight on the front without having to ride on the bars like an MTB to keep it from sliding out even at warp speed on loose & fast corners. To say there is a night and day difference between them is an understatement.
I firmly believe that weight distribution is a key feature hidden within the geometry numbers that many people never consider. TONS depends on a rider, their experience, riding preferences, roads/trails in use and more. Not everyone wants what I want, that’s for sure by seeing the explosion of these bikes. But I know I will never own any of the “new school” MTB style gravel bikes for my needs.
Much like I lamented the “Long, Low & Slack” progression in the MTB world, I dislike the current swing seen in gravel. The options for old school bikes that I prefer dwindle and I consider myself luck to have gotten what I did before they fully disappear.
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Great example. You can clearly see how the Cosmic Stallion has a shorter FC and longer chainstays which puts both wheels “further back” than the other two bikes resulting in more weight on the front.
If that works for you, stick with it! 
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New School Gravel Bikes, in my eyes 
Jokes aside, I totally get how the new stuff works for some riders & use cases, but I also hear about others that have similar thoughts and preferences for the tighter stuff of old.
Largely a guess on my part, but I also think this may be another reason some riders like Keegan downsized on their “new” bikes. IIRC, he is on a Stigmata that is two sizes smaller than the recommendation per the Santa Cruz guidelines. Some is definitely for lower stack height, but in tandem with that change is a much shorter front end and longer stem more inline with older geo & stem sizing. Interesting at the very least even if it only applies to a tiny subset of riders.
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Yes, and it is massive. This video by (Kyle and) April illustrates the point very nicely. Just a very, very subtle shift of your foot position can result in 3.6 extra kilos shifting towards the front. Note that this scales with body weight and April looks very light, maybe 55ish kg? Initially there was about 50 pounds = 23 kg of mass over the front tire, so about 42 % of her total body mass. After this really minuscule shift 26.3 kg was over the front wheel or 48 %. That’s a 6 % shift with a bit of footwork.
Speaking from my experience on the MTB here (although it applies verbatim to all other forms of offroad riding), shifting your weight is crucial in mountain biking. E. g. if you want to rail a corner, you want to squat down towards the handlebars when you initiate the corner. This shifts your center-of-mass/gravity forwards and does increase the grip as the maximum force you can exert with your tires is proportional to the force normal to the tire surface and hence, to the weight you put over your front wheel.
For steep downhill you want to put your butt behind the saddle to put more weight on the back wheel. That serves multiple purposes, one of them being that you can brake better with the rear to scrub off/control your speed. Also, if you hit something, you are less likely to cartwheel as you put less weight (ergo, force) on the front.
It also matters on a road bike, although here you tend to shift less on the bike. On a mountain bike you have much more freedom to shift your center of gravity. On the other hand, even small motions have a significant impact.
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Yeah, it totally depends on the rider, their skills, and the terrain.
As XC bikes move toward trail bikes of only a few years ago, and trail bikes toward enduro bikes, they are becoming more capable.
But what if my terrain isn’t getting more technical? Then why should I get a more capable bike? To make riding this same terrain easier and less engaging?
That’s why I’m riding a MTB with a ~69° HTA. I don’t need a bike designed for the more technical World Cup circuit.
The same goes for gravel bikes. If we all saw up close and in person how fast some of the pros are riding their gravel bikes on the gnarliest terrain, we might tear up a bit. 
Ultimately, I’m not doing that though, so again, do I need a bike that capable? Probably not. 
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I have a bike like that, a 2014 Merida Big.Nine, which, sadly, has become my commuter. Plus, the area I live in is flat, really flat. It is littered with picturesque lakes, though.
I can tell it would be a great gravel bike, the only two things I am missing is taller gears (perhaps a 38-tooth chain ring might fit, but I reckon it tops out at 36 teeth as that was the biggest Shimano 1x chain ring at the time).
I’m running a 34t chainring and I’ve pretty much never needed a bigger gear on the gravel roads around here. It’s really not common for me to be pedaling at 30mph for very long.
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I spend a lot of time on the road and I am often between 34:13 and 34:11. That is the only gear jump that annoys me.
My next bike will be a gravel bike (I’m thinking of Nicolai’s Argon GX as my next frame) with fat, fast tires (helpful for better braking performance with a trailer and 1–2 kids in tow). I’ll slap on fast tires (e. g. Schwalbe G-One RS or G-One Speed) and intermediate gearing.
While I’ve raced gravel a good bit on my MTB with a 38 and I never felt like it held be back, I agree that the chainring size can be a big limitation if trying to use a MTB for gravel/road on flatter courses. One solution to consider is increasing the chainline to allow a bigger ring. When I see Keegan running a 42 ring on his MTB at leadville this year, I have to believe they are pushing out the chainline a bit to fit that 42 ring.
I’ve been playing with parts on my old Spark RC and recently stuck a crank/chainring combo that has 55mm chainline. Running old eagle 12 speed. Officially, I believe eagle wants a 52mm chainline, but it seems to operate fine with 55. Just a little more noise and I’m sure some lost efficiency when running in the biggest rear cog. With a 52mm chainline, the max ring was a 38 on that bike and with the 55mm chainline it looks like there is plenty of room for a 40 and maybe even a 42. I don’t have rings that big for the crank (not even sure they are available), but if I was building that bike up for gravel or road, I’d try running a 40 or 42 with 55mm chainline and see how well it worked.
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I may have done something similar with an epic. It’s been great for chunky gravel races, and it’s quite nice. Definitely takes away climbing gears, but I’m a fan
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This all reminds me of when the Evil Chamois Hagar was introduced. Some immediately said it was the next big thing in gravel bikes (Hi, @Nate_Pearson 
) while others saw it as a niche case bike. I still see it that way……
Most of my gravel riding is on multi-use paths in the suburbs of Chicago. Even if I go out west in the state and ride actual gravel roads, they are still roads, not trails. I basically need a road bike for dirt.
I have also done some of the biggest gravel races out there (Unbound, Big Sugar, SBT, The Rift, FNLD, etc) and have never really found myself wanting or needing a rowdier bike. Maybe on a few sections during The Rift….but I was just fine overall on an Aspero with 40mm. If I did it again, I would definitely run wider tires, but a road bike-oriented geo is still my preference.
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Theres plenty gravel races that are way rowdier than unbound, big sugar, sbt. (No personal experience with rift and finland). There is really tricky gravel out there, just not national level events. Come to appalachia, you will hate 40s and road bike geometry
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Sounds like good candidate for a hard tail MTB?
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But that is my point….i’m not doing those types of races, nor are those types of races the dominant style, IMO.
I’m not saying there is not a place for rowdier bikes….but I am questioning the current design trend going on for gravel bikes as they lean more and more into MTB geo.
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They work well until you hit road sections where you can run out of gears.
a mile long 3% paved downhill…you’re dropped. But you can crush midwest style gravel bikes on the downhills
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