At what point does a HT become better than a gravel bike?

As soon as the bumps become more than gravel sized a mountain bike is better than a gravel bike IMO. So in short, as soon as you’re off gravel roads, you’ll be having more fun on a mountain bike.

Bridleways and mixed riding, I'll take the gravel bike.

Singletrack and woodland bermy trails, hardtail or rigid MTB :). A rigid MTB flies and with a big front tyre and some nice carbon bars like OneUp it takes the sting out of the bumps.

Simple really the hardtail is better when the gravel bike becomes less fun and the MTB more fun.

It's all personal choice. Some of what I ride on a gravel bike might be "better" on a HT MTB but I doubt I'd be having as much fun, in that "throw me a challenge" kind of way.

It's all compromises and personal choice.
I'm all about the fun, not the ultimate speed. And part of that can be being 'underbiked', while enjoying the extra speed.

Would an uber light XC Hardtail on proper fast tyres and wheels be a good comprise?

I think I'd always buy the hardtail.  I just don't get what a gravel bike will give me over a light, racy HT with a clever choice of tires, or at least give me anything I want

But that's just my opinion.  What's your gut telling you?

@prawny I don't suppose it's much help but up until quite recently I e. I just haven't ridden in a while) I used to love riding my fully rigid Sounder Frontier with 29er wheels around the Dog & old blue and it was excellent. With the Frontier you're getting a bit of a mix of gravelish with MTB HT and I can highly recommend it.

Plus of course if you really want to HT it occasionally you just need to fit a 100mm Sus fork when the urge takes you.

Edit: I currently have it set up for commuting with a rack and 2.6 hookworms and that's a real laugh on the roads 🙂

For OP I reckon you'll be happier on a hardtail. If you stick fat slick-ish tyres on there it'll be fast enough on roads AND capable on the fire roads and bridleways.

I always say my 29er is a great gravel bike, and my gravel bike is an extremely comfy road bike.

I'd buy a gravel!  The OP was a roadie so no stranger to drop bars, and a modern bike with discs, slacker geometry and tubeless at the correct pressures will be fun and fast.

An old hybrid isn't really going to compare.

For me if >50% of the ride would be unrideable on a road bike (incl gravel roads that would be crap but still ridable) then I'll take the hardtail.

After riding my gravel bike probably 80% of the time for the last couple of years I've recently got back on the hardtail (SC Highball) and just completely fallen for it again.  To be fair I was probably pushing the gravel bike into more XC'ish terrain than I probably should have but I've re-ridden some of the routes I was doing, including some definite gravel non-xc terrain, on the hardtail and it's simply more fun for me.

In short, the hardtail can do anything the gravel bike can just a bit slower on smoother rides, but there is stuff I wouldn't consider riding on the gravel bike.  The hardtail opens up more options.

I fall off my XC HT harder than my gravel bike..

Rode the HT for the first time in a while last week at Swinley. It creaks a lot, is not as comfortable as my gravel bike and is a lot more fun on the faster, steep, bumpy stuff both up and down.. I could have ridden the gravel bike around the same route (more slowly) and it still would have been fun.

If I had to choose one, gravel bike, as it is fun everywhere, including (gasp) tarmac.,..

What you want there is a rigid MTB aka adventure bike.  They are better to ride than actual HTs because they usually have steeper more road/gravel like angles, and the rigid fork is much more solid and positive. But better than gravel bikes when it's rough. Mine has 2.3 fast MTB tyres on it, a high sweep bar and a dropper, and 1x MTB gears.  It is great to ride on the road, really comfortable and quick, but it can ride anywhere I can ride an MTB just more slowly - much more slowly on certain descents!  I built it for the local riding here which can involve 20 or more miles of road, steep fire road, rocky tracks and the occasional technical descent.

At what point does the terrain start to favour a 29er HT over a gravel bike?

When your ability to ride the gravel bike on the terrain you've chosen runs out.

It’s nice crazy close. Round here I can ride with some one a hard tail and neither bike seems wrong

From what you’ve said I’d go hardtail

For some people bar shape is the deciding factor

I quite like the extra challenge of the less capable bike off road. Which is clearly ridiculous. Terrain that requires no input on my FS bike requires lots of steering on my gravel bike

NB my gravel bike has 50mm tyres. Which gives it chunk more give over the bumps compared to 38mm

As noted above, it’s all compromises really.
however, an mtb can’t really be adapted for road, in the same way that a road bike can’t really do gravel, and a gravel bike can’t really do proper off road.
pushing the limits of a machine can make terrain more exciting though = cx bike on rooty singletrack.

converse is also true though, eg using a hardtail on gravel tracks, = pretty boring.
i have gravel, rigid mtb and FS ebike.
gravel bike gets most use.
rigid mtb probably most fun though.
but that’s me, not you . .

Gravel bikes are ace for any ride that includes a decent amount of road / country lane and/or gravel fire road, hard packed smooth dirt or sand singletrack that isn’t too steep. They’re great for rides with plenty of “up and along” with mellow downs.

as soon as a trail gets even slightly rocky or steep you can still ride stuff but you need to pick your way down and it all becomes a lot less comfortable.

so depends what you’re going to be riding. I’m lucky to have both and most of the really local trails can be ridden on either ( at different speeds) so depending on mood I ride the more technical stuff fast or ride bigger country lane loops linking up the mellower off-road sections and avoiding the rockier ones...

Tricky to say, as the technicality of an trail and it's roughness are kind of orthogonal

I mean, high volume gravel tyres would be great for a slopestyle course, but dropbars would be petrifying

And on tracks that are rough, chossy but nonetheless straightish and not too steep, dropbars are great, but large volume tyres a must (much larger than gravelbike volumes) and suspension is welcome

An XC bike can be just about as quick as a gravel back in most areas except on the road in my experience, and is way more fun off road. I've got 2 gravel bikes and barely used either since buying the XC.

What molgrips says. Rigid HT is great, I'm currently running a Cotic Cascade with rigid carbon forks and flat mtb bars. It's perfect for bridleways and mashing through easy trails in the woods.

Not great on the road, but that's not what I want it for.

Used to ride the Chase trails 3 nights a week when I stayed in Cannock for work (pre-covid).

Rigid Steel HT 29er with carbon fork was perfect.

I bought a gravel bike last year and love it. I bought it to replace my road bike and my hardtail, still have have a full sus for technical mtbing. I have a Cotic cascade with MTB tyres. It's very capable on everything up to steep technical trails and fast enough for me on the road. I think if you get on with drops a fat tyred gravel bike could be a good option. I have a narrower set of tyres which I put on over the winter as I do more road riding.

I’ve just seen the Sonder Dial, that looks like it could be a good value option, not a huge range of xc race HTs at that price.

Otherwise could do with having a go on a day tyred gravel bike. I’m very happy on drop bars

What kind of riding do you want to make the funnest?

Any bike can do anything, within reason.  You could ride most of BPW on a gravel bike, given a certain amount of skill.  Compared to a 150mm trail bike, you'd be more likely to fall off and hurt yourself, and much less likely to have any fun.

I love my 140mm trail bike because I can go ride all the techy local stuff (and anything uplifty I'd want to throw myself down) pump and push through turns, explore the far limits of my jibby, jumpy type riding, have a ton  of fun and string a 50 mile loop together, though some bits will be a slog.

I love my gravel bike, I can ride most of the local techy stuff, but the buzz on that bike is that it feels so good and so right to absolutely pin it on otherwise non-descript traverses, road sections, slight uphills, stuff that would just be a twiddle and and a time to think on the trail bike.

I go further, see more on the gravel bike, get more value from the flatter areas, rinse myself with the distance.  I hug the steeps on the trail bike, get the value from the tech and the skills, rinse myself with the climbing.

HT and gravel are a bit closer, but the question's the same - what do you want to make the most fun?

@charliedontsurf did a graph once. It was a good graph. Jones Spaceframe covered most of it.

Hand on heart. The second you through a leg over 🙌🏻

HT and gravel are a bit closer, but the question’s the same – what do you want to make the most fun?

Rigid closer still, potentially. Tyre pressure can change the rigid bike from more like a hardtail (without suspension you have to pick your lines carefully with) to more like a (flat barred badly geared for roads) gravel bike... that can still handle some jibbage 😃

I'd say the point where drop bars are taking the fun out of it.

I did a demo on a Cotic Cascade a few months back, I loved it, truly, for climbing and riding along but I am definitely not a drops on the downs kinda guy.

I bought a second hand Pinnacle Ramin 1 with 2.1 tyres and no suspension as a stop gap. By far the best bike I've owned for mile munching go anywhere fun. (yes, this is probably the third topic I've waxed lyrical about it today, I know). Still got the original X Kings, will take a set of Mezcals and nicer wheels but that's just a nice to have for tubeless.

I'd say the point of ditching a gravel bike is when you need that extra volume, say a Cascade or Alice for the drop bar fans or just an old school 29er for flats. They just make so much more sense.

I’d say the point where drop bars are taking the fun out of it.

Agree.  A gravel bike on 45-50c tyres is not going to be that different than an XC bike on fast 54c tyre when it comes to speed other than being able to get into a faster position on the gravel bike.  The difference in that position is not that big though as typical position on an XC bike would have body at similar angle to riding on hoods on gravel bike.

I used to swap bars between flat and drop very regular on the same bike and rode on road, gravel and easy off road and the difference over an hour or two was not noticeable in terms of time but the flat bars just felt more fun.

I would probably go flat bar gravel bike just because it would be lighter than XC bike unless you are spending £10k on the XC bike.

For me it's when the speed gets higher AND the surface gets rougher.

Rougher, rubblier gravel at slow speeds, gravel bike still fun 👍

Rougher, rubblier gravel at high speed (like those long, fast landrover descents in the Highlands which are liberally covered in loose rocks) gravel bike still fun, but rim and tyre damage less so 🙄

My own fault for building a gravel bike that can only take 40mm tyres I guess.

I'm a big fan of my fully rigid 29er MTB over my 'cross bike. Just works better across the range of trails from my front door in Sheffield. Perhaps if I had a gravel bike with 50+ width tyres it would be different but then you're going to lose fast tyre speed on the road and it will still be worse off road.

My fully rigid mtb built light and with a racy lowish front- Alu frame, carbon fork, 1x12 (ok boat anchor cassette), carbon bars, hope pro 2 on stans crest, schwalbe Racing Ralph's.... It's my most used and arguably most versatile bike.

If I were to have one - fully rigid mtb or gravel - it would be the MTB for sure. But I'm lucky to have both.

I would go gravel. You can do anything you like on a gravel bike although maybe huge junps could be terminal. It is all a matter of neck and muscle. But if you end up doing a lot of rooty stuff or brick sized stones those suspension forks on the MTb would be worth the money.

How about a MTB  and a set of carbon rigid forks. Wheel out, caliper undone and it just a quicker fork drop out to swap. Thus you can have a flat bard GB or a MTB.

Go HT and forget about whether you're 0.2mph quicker on the road 🙂

Echo most of the above and ultimately it depends on how much one can tolerate being thrown around if riding any rigid bike off road.

I've had most types of bikes and also ride Cannock a lot. The old blue, especially when tied into some over to top bits and the longer old blue is great on a light hard tail. For me, my gravel bike (Sonder Camino with 45C tyres) is good for 80% ish but, there are a few bumpy bits where I get annoyed.

Overall, for Cannock and similar riding where it is all off road but a bit more than gravel, I'd have a hardtail 100%

I had an On One Whippet (new one), rigid with carbon forks and built up to under 10Kg. It flew over the blue and managed ftd well but, it was still a little bit more challenging than the HT - not necessarily less enjoyable though - apart from bits where it was a bit rubbish, which brought the whole experience of said ride down quite a bit.

What made my choice was to get the rigid mtb to the bike I wanted to ride, made it very close to my main HT, so I sold it and built the Camino instead. That does 99% of what the Whippet did but, is great on road.

To summarise, I'd say if there is a larger percentage of road riding involved, or 'proper' gravel riding involved - and you don't want to be too extreme, gravel bike all day long.

For everything else, HT until it gets rowdy or shiny black stuff starts to creep into rides and speed / distance become the main targets.

I think I’d always buy the hardtail.

Same here, gravel bikes are either boring on a smoother surface or roads which to be fair; is always the case regardless of the bike you're riding,  or out of their depth on anything remotely tech (aka interesting and fun) So you're reduced to linking bits of canal towpath, ex-railways or bridleways together

And this is the issue with gravel - it's limiting. If you're a roadie, I'd imagine that those sorts of surfaces are interesting, challenging and different, if you come from an MTB background, then they're the bits you use to get to the interesting stuff. Setting off on a ride to purposely stick to those sorts of byways just seems like such a wasted opportunity.

Whereas I don't find any riding boring (okay, maybe a low geared SS MTB on the road!).  Currently only have a road bike and enjoying every ride, even the ride just now in the pissing rain.  But then I enjoy riding a brakeless fixed gear off road so may have a different perspective of fun.

If you live next to the Chase and will ride there mostly get an MTB for definite. That gives you the option to explore more.

If you're thinking you'll ride more of the lanes in the Staffordshire country side get a gravel bike.

My usual weapon of choice is my Stooge. I also live on the edge of Cannock Chase (Stafford side) and that bike has taken me on many, many rides in the area including stuff like the Giant Challenge which is mixed off/on road. BASed on that I'd get a nice hardtail or rigid MTB.

OP, if you already own a Full Susser, are used to riding road bikes and are looking for something that can do road and trail and everything in-between then a gravel bike is a good option. A decent, modern HT plus a reasonably skilled/experienced rider will be able to handle a lot of what the FullSusser can do but A decent modern gravel bike can do a lot of what a modern hardtail can do, just minus the suspension forks, hence the cries of "its a late 80's mountain bike" although I think a lot of people are perhaps viewing those bikes through rose-tinted spectacles (or possibly varifocals as they forget things like modern geometry, 29in wheels, disc brakes, decent gears, Tubeless tyres etc etc.

Would I ride a gravel bike around a trailer centre? Hmm... well I wouldn't mind trying something like Blue Scar at Afan (now thats got me thinking...)  but Pennydd, the Wall, Skyline etc? No way. I'd happily ride anything there on a Hardtail but Id want to be on a full susser as I am both old and a wimp.

As for exact location the weird, blurry, ill-defined boundary that separates a modern Hardtail from a Modern Gravel bike, who knows? TBH, just try a gravel bike, see if you like it.

Spa Cycles Rove in steel or Ti?

New Singular Swift MK5?

Would I ride a gravel bike around a trailer centre? Hmm… well I wouldn’t mind trying something like Blue Scar at Afan (now thats got me thinking…) but Pennydd, the Wall, Skyline etc? No way.

It depends on what you consider fun.

I've taken a gravel bike around QECP red and rattled around Glentress Blues and Spooky Woods on one with slick tyres, mudguards and a rack - but I was concerned for my rims...

It depends on what you consider fun.

I’ve taken a gravel bike around QECP red and rattled around Glentress Blues and Spooky Woods on one with slick tyres, mudguards and a rack – but I was concerned for my rims…

I just don't see how that is or could be 'fun'.... it must be sodding horrific.

I just don’t see how that is or could be ‘fun’

Some of the satisfaction comes from what you don't know - and some from being ridiculous 😎😂

And some by keeping up with 'faster' bikes

I’ve got an old voodoo hybrid so I took that round the old blue route and it was terrifying in places, proper bone shaking no grip on the loose stones, didn’t really enjoy it.

That's your answer really isn't it. If the sort of stuff you're going to mostly ride on a gravel bike is like that, then you're probably better off with a hardtail. You can, of course, stick 650b wheels in with mountain bike size tyres, but then why are you riding a gravel bike in the first place unless you're also putting in a fair few road/hardcore surfaced miles in as well.

'Better' is a subjective judgement anyway. Is 'better', faster? More fun? More comfortable? More stupid? If you're someone who likes the thing of riding inappropriate bikes for the conditions then gravel bikes on mountain bike terrain are ideal. If you just want to ride with an appropriate bike for the conditions then a hardtail arguably makes more sense.

If you want a bike you can also ride on the road and rough back lanes in particular - and more so with a change of tyres - then gravel bikes make more sense. Unless you want to stick slicks on your mountain bike and do the whole sail in the wind thing.

In the end it probably comes down to the balance of your riding between off-road and on-road. And in turn, what bike you ride will probably affect that too. Can you not just have both in a cake and eat it sort of way?

but I was concerned for my rims…

How were your wrists? Taking a rigid mtb down rooty brake bumped trails is bad enough!