To be fair I thought the same until I read that they were 700c not 650b - that’s pretty big clearance.
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Some gravel bikes require 1x, but many still support 2x, yet they all nearly ship with 1x. I’ve felt that was to segment them from road bikes: if you want to go fast, buy a road bike too. There seems to be evidence for this with the 1x gearing, like SRAM’s XPLR: it can’t climb the grades you encounter offroad (so you need to buy an mtb), nor can it go fast on flats and down hill (so you need to buy a road bike). If I’m going to take the compromise of 1x (presumably to handle mud), I at least want 520% gearing to spend more time in zone 2 on the climbs (I do polarized training).
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Really?
A gear ratio of 38:10 = 3.8 gives you 46 km/h with 40 mm tires at 90 rpm. At 100 rpm you’re doing 50 km/h. Are you regularly going faster than that on the flats? I reckon at those speeds your gravel tires will be the limiting factor, though.
When you go down hill you indeed spin out earlier. But on a gravel bike, does that matter? On public roads, do you really want to continue to pedal upwards of 60 km/h?
Stating that they aren’t as fast as a road bike (with gravel tires anyway), nor can they cope as well as with rough terrain as a mountain bike is looking at it from the glass is half empty perspective.
It’s mostly down to route choice: there are plenty of routes I don’t want to take with my road bike either, although I could do them on a gravel bike. Gravel bikes aren’t made to replace mountain bikes, so you wouldn’t want to ride as steep a gradient with them. Mostly, gravel bikes are meant to be more versatile than either road bikes or mountain bikes. But the tradeoff is that they are less optimized for a specific task.
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Those numbers don’t work out well for me, since I must tailor my gearing for one ride to have extreme climbs, flats, and fast descents. I don’t consider it glass half empty when the options of 2x and 1x with 520% exist — I use those and criticize the EXPLR option most gravel bikes use (SRAM could have added a longer cage to take 520%). I agree that route choice is important, but I disagree about how to divide between my bikes. I divide based on suspension, not gearing. If I’m going to descend dirt, then I’ll use suspension. But I’ll climb steep singletrack grades with my all-road bike on 650b 48mm slicks and then descend pavement, to keep the overall pace of the ride, from my door, fast.
I don’t think you are missing any gears on the flats. Are you going faster than 50 km/h on (false) flats with gravel tires regularly? Do you need to pedal on descents where you exceed 60 km/h?
IMHO most road bikes are ridiculously overgeared for most people. Even “gravel gears” are too hard for most.
That’s a weird criticism since SRAM offers solutions with more range: you can pick between 1x and 2x options with a gear range of 520 % and 516 %, respectively. The lowest and top gears are not necessarily identical, but at least on 1x you can pick your chainrings accordingly.
Maybe our philosophies are just different. When I ride my bike, I want to have fun or relax. When I want to relax, I often opt for my hardtail even for routes that are mostly paved. And when I want to have fun, it depends on the day. Sometimes being underbiked or being on the wrong bike can be fun. Being undergeared would be part of the fun.
So if doing single track on 48 mm slicks is fun for you, more power to you. But I wouldn’t impose expectations that this bike needs to match a road bike when on road.
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Is this all because MTB trails are becoming more technical? So you either need to keep up with skill/bike capabilities. Or ride a non-technical single track on a less capable bike.
The big tyres seem like an advantage to me, if you’re doing gravel races with single track.
One reason to not bother with 2x on a 2.2"+ tyre is the rolling resistance is going to start getting to the point where pedaling at 50+ km/h is going to be a huge wattage suck.
Gravel riding seems cool to me in a - get away from cars - type of way. For me I’d rather just ride my MTB, especially if you’re running MTB tyres anyway. Gravel bikes are fast though.
Those tires were not a bad idea for that specific course, in fact very appropriate. Anything above 40 with a lot of knobs. It was a fairly technical with nasty descends.
I already have 2 sets of gravel wheels and I can see myself having 2 gravel bikes soon. I also have a MTB and there’s no way I can use my gravel bike in any of the MTB routes I do.
So yeah 3 different off road bikes.
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And plenty of people do gravel races on mountain bikes and enjoy it just fine. I definitely like my gravel bike with big tires. I have the lauf true grit and have size 45 tires on it. It’s a nice ride. The tires are pirelli cinturato m. Little knobby but great for daily use. For a little speedier tire I like the pathfinder pros.
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It looks like I could get an EXPLR with 40t + 10-44t. It’s lowest gear ratio is 0.91, which is way better than a 2x road. And its highest gear ratio is 4, which is around 29 mph on medium sized tires, which is plenty fast. And you were suggesting 38t, which is even a better low gear, and like around 27 mph if I use medium sized tires. That still is slightly faster than my mtb which I’m frequently spinning out on despite bad aero. So it looks like either the 40t or 38t could work for me. Thus this Seigla might work for me, it is a good deal, and I just have to convince myself that 2x is ok to give up.
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Out of curiosity, what cadence and tire size did you plug in to get those values? I know that self-selected cadence varies, but for most people at high speeds (= high rotational inertia) that is 90–100 rpm.
Personally, no matter if you go 1x or 2x, I’d prioritize climbing gears over gears at the top end. When I picked my gearing for the road bike I bought last year (1x12, 42-tooth chain ring with a 10–36 cassette), I carefully paid attention to the gears I actually needed and sized my chain ring accordingly. I could have gotten away with 44- or 46-tooth chain rings, but at the expense of harder climbing gears. On my road bikes, I have used the top gears almost exclusively as overdrive gears when I go downhill. The stats I have since collected with the SRAM eTap app have confirmed that.
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I don’t have a gravel bike, but would only buy one with a 2×. 2 weeks ago at a 160km (7000 ft of climbing) gravel race, i was definitley under geared with my MTB with a 36T chainring (largest that fits on my bike). With big climbs in Colorado, I still would want the lower end gears. I spent an enormous amount of time in the “inefficient” 10t cog (12th gear 68 minutes, and 120 minutes on the 11t), see below snapshot from the AXS. Would have been so much faster with more gears…Time for MTB season. For gravel, thinking about tuning up (and dusting off) my circa 1994 Cannondale F3000 with cantilever brakes and a triple chainring! The geometry is getting there, and it already has a 60mm headshock.
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Point me to the calculator/formula used to insert gearing and cadence and get speed etc.
Want to play with some scenarios for myself.
80 minutes in 11th gear but get your point you making.
Seems like it was a downhill race with almost no time climbing or doing hills looking at the ACS report to time spent in gears.
There was climbing, and it was a round trip! Started and ended at exactly the same place.
I recommend you try this website: you can change everything graphically. I have populated it with two of the configurations you were looking at.
By default the speeds are calculated at a cadence of 90 rpm. On the flats at speed my cadence tends to be higher, 100ish rpm. But that’s my preferred cadence, not necessarily yours.
You can also toggle to gear ratios. When you compare gear ratios, keep the absolute value in mind: a difference of 0.05 will be much more noticeable for climbing gears (e.g. 1.20 vs. 1.25) than on the tall end (say, 4.55 vs. 4.60).
Personally, I’d pick your desired climbing gear ratio and then err on the side of having a slightly easier climbing gear. But missing another gear at the top sucks much less than grinding uphill at a snail’s pace.
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Thanks man.
I think a lot of non-pro (us type) cyclists tend to think we need those extra high gears/ratios for fear of spinning out yet those gears are mainly used on downhills and to get to spin out, one needs to climb up the other side and not grind it out. More time is lost on climbing than can ever be made in speeding downhill. That’s just simple math.
The other point is that how often can non-pro’s ride at +40kph for lengths at a time? Yet the main focus is on being under geared at the top end when discussing gearing.
Me thinks the practical aspect of one’s riding needs to be considered above the hype of having high end gearing.
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In my mind when you want to choose your gearing, you think about climbing gears, cruising gears and overdrive gears. Your overdrive gear cannot be tall enough. If you make yourself aero and have the gonads, you can spin out a 55:11 = 5.0. So IMHO that’s the lowest priority.
For cruising, it depends on your fitness level to some degree, but if you are generous and set 45–50 km/h on a road bike, 38:10 = 42:11 is sufficient for that. The hour record for women was broken on a bike with a fixed gear of 58:14 = 4.14, i. e. easier than 42:10 and roughly equivalent to 50:12.
That leaves climbing gears. This is where you can cause or avoid a lot of suffering. I have never heard someone complain, because their climbing gear was too easy. Usually they had run out of climbing gears and were forced to grind along at 60 rpm.
Quoted for truth.
That’s why IMHO you should always prioritize having sufficiently easy climbing gears over having overdrive gears. Plus, it isn’t just about time: if you spin out at 55, 60 or 65 km/h, you are fast and you don’t have to do anything to stay fast. But if you are missing an easier gear and have to grind uphill, that’s … not fun.
I see so many people who are torturing themselves, because Shimano doesn’t believe in easier than 1-to-1 gearing on road bikes. You can get easier gearing, but you need to go beyond what Shimano officially supports. So most people I know do not do that, which is a pity. I think giving people proper gearing would make our sport more attractive to the masses.
If you are riding by yourself, sustaining 40+ km/h is possible for very fit amateurs, but even then all stars need to align — wind, terrain and you need to stay aero. In a group it is much easier. But even then you are talking about a group of fit individuals.
Plus, I’d reiterate a point from earlier: to make a gravel bike more versatile, you need to make some tradeoffs. On gravel tires, the cruising speed is lower because of the added rolling resistance. And likely, you want to climb steeper grades in slippier terrain, so you want lower gears.
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Hardtail or even fully rigid MTBs have long been better than gravel bikes for anything gnarly. To me when a gravel bike becomes terrible for road transfers in between the gravel it becomes pointless.
Sure, but it doesn’t have to be an “either / or” situation. You can balance both needs.
I run 29 x 2.1" Thunderburts on my brawler wheelset and I am honestly blown away by how fast they roll on everything, including pavement even running low 20’s for pressure. I frequently spin out even with GRX 2x11. After race season I may start running them exclusively because it is much less of a compromise than I thought it would be and so much better on the rough stuff!