Sorry if these questions have been asked before but I’ve only ever ridden on road and now want to get into gravel and my rim brake with skinny tyres won’t work, so it’s a great excuse for a new bike!
Ideally I want something that can do road and gravel but I have no idea what tyre clearance or gearing I will need, the images are the British terrain I want to cover, obviously it rains a lot here also, so that would make it a bit worse, I suppose there will also be unavoidable grass and muddy sections but I don’t want to get into single track riding really, what do you think I need?? Edit* I should add I’m not going to go down the bike packing/epic ride route, more just weekend warrior smash out a 3-4hr ride with not too much mud!
IMO 40-42mm is the sweet spot for tire size and if you’re going to deal with mud, the more clearance around your tires the better for keeping everything clear and unstuck. Outside of that, it depends what you want to do on your gravel bike. For racing, you’re going to lean towards certain bikes. For bike packing, you will have a totally different group of bikes to consider. I guess the other consideration is 2x or 1x. Again, if mud is a large part of your future, 1x simplifies things and is easier to keep clear/clean and working in bad conditions. But if you climb a lot, a 2x is nice to have as well. I would say answer those questions of what kind of gravel riding you care about and then you will have a narrower field to choose the right tool for the job.
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Thanks, I’m leaning more towards quick and dry rides rather than epics, not racing but a fast few hours on the gravel with no cars appeals to me, I will do some normal road also as I’m surrounded by them, I’m just not sure how you balance that with tyres and gearing
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I would lean towards a 2x then. I’m on my first 1x setup now and the only time I get spun out is fast stuff on pavement. The Aspero is basically a road bike w better tire clearance so you can ride gravel. That thing with 38mm slicks would probably be nice and fast on any surface. There is a thread in here about best gravel race bikes with a lot of chatter. I know you said you won’t race necessarily, but it still sounds like you’d rather have something that can cruise along pretty well and since road and gravel are in play, that is probably where you will be happiest…on that type of bike. Some of my favorite rides are road rides on my gravel bike. It is plenty fast to keep up on a normal group ride and the added comfort of those tires on pavement is fun. I have a Canyon Grail btw. If you wait for the new Grail to come out, which is supposed to be any day now, that might be a good one too. No more polarizing hover bar to worry about. Good luck!
As wide as you can fit
I agree with above that 40-42 mm looks fine for that. The wider you go, the more comfortable it’ll be and the faster you can roll through the rockier sections. But going really wide does have its trade offs (both the wider tire itself as well as the geometry of the bike that is needed to accommodate said tires). I run 40 mm tires and have a lot of similar terrain and it’s fine. There are some sections of some route where it would be nice to have more volume, but when I come across patches like that I just slow down and pick my way through.
As for gearing, everyone is a little different. I run 42x10-44 on my gravel bike and am happy with it. But it really depends on your fitness, how steep the hills are you ride, and how important being able to go downhill really fast is. As well as how particular you might be about jumps in between gears
Apparently science says bigger tires are faster and more comfortable. Santa Cruz Stigmata has clearance for 50c and Factor has 45 or 47.
Imo anything over 40mm is overkill for that. I’d still go for something with a bit more clearance, so you can fit knobbly tyres for when it gets muddy.
True to a point, but there’s necessary nuance missing or we’d all be rolling gravel on 27.5" x 4" fat tire drop bar bikes 
Point being that the larger tire at lower pressure has the greatest benefit when road surface is not smooth. The rougher the surface, the better a larger and lower pressure tire setup does. It’s about decreasing the vertical displacement of the axles (and therefore you on the bike) in space.
The caveats come from the fact that on a smooth surface, a large tire like a 700x50 tire will be slower than a 700x28. In a smooth situation, there is minimal vertical bounce issue, to the potential benefit to the larger tire is not gained while it loses in mass and rolling resistance compared to the tire nearly half the size.
So considering tire size with respect to surface conditions (roughness in particular) are important if “speed” is of interest. For someone who has mainly “hero gravel” with minimal rocks and bumps, I see anything over 42mm as overkill and likely unnecessary. That said, larger tires can be useful in the bumps as mentioned, but also if there are loose conditions like dust, sand or small rocks on the road surface. That size and appropriate tread are often superior to smaller tires.
Like anything here, there are few absolutes so the challenge is to consider the benefits and compromises to pick what’s best for each individuals needs. In the case above, I’d not want anything over 40mm for my own preference.
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while you may not run them, I would not buy a gravel bike that can’t clear 45s. No reason to limit yourself with a bike that can only do narrower tires. You never know what the future holds and may find some bumper gravel and decide you want bigger tires.
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Agree with most of the above.
40mm or so tires. Buy a frame with clearance for more, just in case, but 40mm gives you a ton of options from really fast Conti Terra Speeds to something that looks like a mid-90s mountain tire. The latest gravel tires are really fast, barely slower than a 32mm road tire.
1x is great for a dedicated gravel bike, or particularly courses and types of riding. But for mixed riding on pavement, I prefer a 2x to keep the closer jumps on the cassette. An Ear 1x13 might be an exception - the numbers looks decent, but I’m unconvinced by the 9t cog.
You might be able to get by with 1-1 gearing (normal compact crank and 11-34 cassette) but at least for me, that’s not quite enough. I run a 33/46 crank and 10-36 cassette. As all the manufacturers do different cassette and cranks now, you have to do the math to figure out which gear sets are equivalent.
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Just chuckling to myself that anything under 45 is now considered “narrow”…only a few years ago, 40 was considered on the wider end of things.
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No kidding. Not saying it’s right or what others should be doing, but I spent years riding some of the nastiest river rock encrusted gravel in our area on 32mm CX tires. I have moved onto a nice 40mm tire setup now that adds comfort and grip appropriate to the rather chunky stuff we have for my daily rides.
The range we have is great, but I see some of this as parallel to the MTB world with people over-biking by riding 150-160mm travel fully’s in places where a modern 120-130mm down-country bike would shred. They do that for that random drop or rock garden in mind but it’s far more than needed for the bulk of the trails they ride.
Run all the tire you want, but I can’t stand hauling around that extra amount 90% of the time for 5-10% of edge case uses.
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Not where I live, we’ve been riding 45s for 10 years
Just this afternoon I fitted a new pair of G-one RS’ in a 45 to try out for a bit before next year. I was running 40s prior, but we have a lot of pretty chunky and loose gravel where I am. It’ll be interesting to see if the rolling benefits outweigh the aero and weight penalties of the slightly wider and heavier tire.
If it was packed dirt I think a narrower tire would be fine, but constantly riding over loose rocks and washboard, I think the wider tire may be the way to go.
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