As I said earlier, I’m quite happy to accept that I may well be wrong. There may be a good reason why a road/gravel bike is better with a steep head angle, but I’ve yet to hear a reason that makes sense for me.
I'm simply giving you my opinion based on riding road bikes with traditional "racing" geometry. I don't find them unstable or twitchy to ride - quite the opposite. I think there's a risk of getting too hung up on the numbers - notionally my gravel and road bikes have similar geometry but they don't ride anything like the same.
"I don’t find them unstable or twitchy to ride"
That may be, but can you stop anywhere near as quickly on a road bike as on a longer wheelbase mountain bike with a dropper post? This is what I dislike about road bikes when commuting, they're simply not as safe!
That may be, but can you stop anywhere near as quickly on a road bike as on a longer wheelbase mountain bike with a dropper post?
Eh? I don't see how brakes are affected by dropper posts.
Eh? I don’t see how brakes are affected by dropper posts.
Really? I hate dropper posts and even I can see how they'd let you brake harder. It's simple physics.
The numbers don't necessarily match those above, but the Bombtrack Hook EXT is a lot of fun in the way you describe
Fun
The main reason for why a road bike doesn't stop as quick is simply down to the size of the tyres, particularly skinny 23mm tyres pumped-up rock hard. I've ridden and raced all bikes, from road bikes, criteriums, CX, MTB and multi-day endurance events - you simply get used to the handling traits of each.
Really? I hate dropper posts and even I can see how they’d let you brake harder. It’s simple physics.
Please explain.
Really? I hate dropper posts and even I can see how they’d let you brake harder. It’s simple physics.
This assumes that you drop the saddle each time you want to brake. Not sure that process is going to shorten the braking distance.
“This assumes that you drop the saddle each time you want to brake. Not sure that process is going to shorten the braking distance.”
The only time you’re going seriously fast on a bike is downhill. I drop my saddle for going downhill, whether I’m commuting on the road or MTBing. It’s safer on the road and more fun off-road.
“Eh? I don’t see how brakes are affected by dropper posts.”
If you lower the centre of mass on a vehicle you increase the max deceleration before the rear tyre lifts and before the whole vehicle flips over the front wheel (if there’s enough tyre grip). Lengthening the front centre helps too.
I’ve become very much aware of this because I got my old Brompton out of retirement last week. Now that is even shorter and steeper than a road bike with an undroppable saddle. The hills of Brighton are far scarier than on my usual (inappropriate) commuting bikes (well maybe the motorised Levo isn’t inappropriate despite the six inches of suspension and big knobbly tyres, but my equally gnarly hardtail certainly is!)
If you lower the centre of mass on a vehicle you increase the max deceleration before the rear tyre lifts and before the whole vehicle flips over the front wheel (if there’s enough tyre grip). Lengthening the front centre helps too.
No, I get why dropping the post to get your weight back is helpful off-road, it's just that I don't think it's remotely relevant to road riding. I can brake very hard from the drops without any fear of going otb.
Thanks for keeping this going folks. Some very interesting points. @chiefgrooveguru is basically making similar arguments to me, with more experience to back it up 🙂 I’m still on the fence a bit though. I totally agree that increasing the front centre requires an increase at the rear too in order to stop the front getting too light. I don’t mind longer chainstays really though as they improve comfort. But the consensus is that power delivery isn’t as good (although I’ve not seen proof of that) so maybe that is the limiting factor. You don’t want the chainstays getting too long (for efficiency) which limits how long/slack you can go at the front. Well it’s a hypothesis I guess :j
But the consensus is that power delivery isn’t as good
Fair hypothesis .. I think that's mostly misconceptions from the road racers though tbh. It's like the stiffer frame vs the more flexible frame, the response time and feedback from a longer rear may feel different but overall power delivery needn't be affected in a way you could measure. Adjust your riding to the bike and it's still efficient. A racer wants a snappy response but that's about racing responses more than any power losses. And a lot of small gains do add up so it's part of race bike design.
I'd say you don't want the CS to be too long in balancing that longer front as it just doesn't follow tighter road corners well. Means you need to really commit and force the front round more, and that's more likely to mean a slide in the wet or on gravel - the thing you're trying to avoid by going longer and slacker if I understand the OP. Let's say you went to 660mm front centre, it's not that long. By road bike front/rear centre proportions of (eg) 59%/41% you need a 458mm CS to balance it up (assuming the same rider position over the BB). I've ridden a drop bar all-road bike with ~those dimensions, as you'd expect it's great in a straight line on a choppy byway but useless in the hairpins. You could adjust the rider position to reduce CS length and still keep weight on the front wheel but then you're getting close to the 'just get the light rigid 29er out' stage since you'll need to adjust how you corner etc anyway.
It's like the bars and tyres compromises all-road bikes force us to make - how we ride and corner is also different between road and off-road bikes and a middle-ground design's validity is subjective, varies by rider preference.
I’d say you don’t want the CS to be too long in balancing that longer front as it just doesn’t follow tighter road corners well. Means you need to really commit and force the front round more, and that’s more likely to mean a slide in the wet or on gravel – the thing you’re trying to avoid by going longer and slacker if I understand the OP. Let’s say you went to 660mm front centre, it’s not that long. By road bike front/rear centre proportions of (eg) 59%/41% you need a 458mm CS to balance it up (assuming the same rider position over the BB). I’ve ridden a drop bar all-road bike with ~those dimensions, as you’d expect it’s great in a straight line on a choppy byway but useless in the hairpins. You could adjust the rider position to reduce CS length and still keep weight on the front wheel but then you’re getting close to the ‘just get the light rigid 29er out’ stage since you’ll need to adjust how you corner etc anyway.
It’s like the bars and tyres compromises all-road bikes force us to make – how we ride and corner is also different between road and off-road bikes and a middle-ground design’s validity is subjective, varies by rider preference.
i'm sure that's exactly what i said on page one but with much less eloquence 🙂
btw i rode an Arkose yesterday and it's not far off what the OP wants, slack compared to a road machine but not upright like a hybrid. very nice off road with 42mm resolutes on it
RD - yes - balance is the thing isn't it. But who's less eloquent? : )
So what is it that makes the fundamentals of road bike handling so different to MTBs? Is it the high saddle and drop bars so you lean in unison with the bike, is it the skinny tyres, or is it something else?
having seen one in my LBS i really fancy a Rondo Ruut CF2 but then i also want a Ribble Ht Ti, and a new motorbike!
So what is it that makes the fundamentals of road bike handling so different to MTBs? Is it the high saddle and drop bars so you lean in unison with the bike, is it the skinny tyres, or is it something else?
The handling is quicker due to the geometry (angles and bar height). I had an MTB which was made for a 100mm fork and I fitted a rigid carbon fork that was shorter. It ended up feeling very much like a road bike as saddle to bar drop was large and head tube angle was around 73 degrees.
I actually ride a track bike with risers and it felt the same as that as far as steering was concerned apart from one thing, the tyres. Narrow tyres make the steering lighter and quicker due to less friction onto road combined with lower forces side to side due to less weight.
I recently changed from 28c to 23c (same model of tyre) and even that difference is noticeable and the bike feels more agile.
“The handling is quicker due to the geometry (angles and bar height).“
That’s not what I’m talking about. Show me any road and I’ll show you a million bits of singletrack which are far more twisty - yet with MTBs we’ve seen a shift to much more stable slower steering behaviour. Why is that a good thing on a MTB but a bad thing on a road bike?
What is the fundamental difference in how you ride the bike or the effect of the other unchangeable characteristics (narrow bars for aero, narrow tyre for rolling resistance, etc)?
On a road bike, even in the middle of a turn, it just feels too light to feel confident leaning into it.
Maybe your brain has adapted to the heavier input needed to steer a lomg, slack mountain bike and you have trouble modulating your input to a quicker steering road bike. Relativity is an odd thing. In a previous life I road-tested motorcycles. To begin with, I found it really hard to swap between different types of bike - trail bikes, race replicas, hideous chopper-styled, raked out Harley replicas etc. After a year or so, I got really good at it.
Similarly, I rode a borrowed Trek Full Stache for a day on local trails. It's like a monster truck. Before I rode it my Sonder Transmitter felt long and slack. After I swapped back, the Sonder felt like a BMX. Go figure.
Finally, yes there are slower steering road and gravel bikes because tourers and sportive riders don't need the sort of reflex-sharp steering that pro racers do, but they don't need to be as slack as a mountain bike to be appreciably more relaxed, there's a smaller envelope. Oh, and some people just prefer a sharper steering feel because the bike feels lively and fast on a subjective level.
Also, how would relatively narrow drop handlebars cope with the steering input potentially required for slacker geometry or would you just fit 800mm flat bars?
Why doesn't everyone drive a slow, steady, stable, Volvo estate? Why aren't all running shoes massively cushioned? Why wpuld anyone eat chips when you could have rice, which is easier to cook?
Ultimately, I guess the answer, if you want such a thing, is to get a road/gravel frame custom made to your favoured mtb geometry and see how it rides.
I think a lot of it is to do with body position onnthe bike as well.
On a road \ gravel bike your body is much more stretched out, with more weight further forward compared to an mtb. So turning and direction changes are much more subtle, I think this would lead to 'oversteering' with a really slack head angle. As the front would pitch over due the weight distribution.
Hopefully someone else can explain this better than me 😂
Show me any road and I’ll show you a million bits of singletrack which are far more twisty – yet with MTBs we’ve seen a shift to much more stable slower steering behaviour. Why is that a good thing on a MTB but a bad thing on a road bike?
Because the terrain is rougher, throws steering off etc,. On the road the movements are small and it is nicer to have quicker responses to them. And by the way I preferred riding an mtb with quicker steering on twisty single track hence the short fork I put on my bike.
That’s not what I’m talking about. Show me any road and I’ll show you a million bits of singletrack which are far more twisty – yet with MTBs we’ve seen a shift to much more stable slower steering behaviour. Why is that a good thing on a MTB but a bad thing on a road bike?
I'm not convinced that it is a good thing on a mtb in twisty singletrack.
The problem I have with these sort of threads (no offence OP) is that I am happy to accept that some people have different preferences when it comes to bikes. Maybe road bikes don’t suit you, which is fair enough. But suggesting that all road bikes are therefore wrong is ridiculous. I can still remember getting on my first road bike over 15 years ago and thinking ‘My god. What have I done?’ You get used to them. A nimble, precise handling road bike is a joy to ride.
And by the way I preferred riding an mtb with quicker steering on twisty single
Every time, LLS comes into its own the rougher and steeper it gets. If your not riding that quicker handling bikes can be more fun.
I am happy to accept that some people have different preferences when it comes to bikes.
Exactly. There is no real right or wrong, just preferences within boundaries. I love the bike I ride for road, gravel and small bits of single track whereas most people would probably get off it in a few hundred metres and put it down and never want to ride it again!
Lots of really interesting comments and bike suggestions here. I’d be here all day trying to respond to them all but I have read, reflected on and appreciated them all. Thanks.
I did spend over 30 years as a roadie and enjoyed nice tight handling road bikes. But I’ve spent the past five years riding almost exclusively off road on bikes that have got progressively longer and slacker. Now I’m looking for a bike that can do a bit of road and a bit of trail and find myself questioning why gravel bikes seem to mainly adopt road geometry. Not saying it is wrong, just questioning.
So, lots of the points about it being what you are used to are very valid.
We’ve also had the rise of gps and apps like Strava over the past few years which have highlighted (to me at least) that feeling fast isn’t always the same as being fast. Although feeling fast/fun is a perfectly good reason to choose a bike.
Finally, for now, there is nothing new under the sun of course. Those rough stuff people were taking “touring” bikes off road before I was born and I suspect that all my thinking would just bring me back to a bike with touring geometry and disk brakes in the end. But I’m one if those weird people that enjoy a good think 🙂
Show me any road and I’ll show you a million bits of singletrack which are far more twisty – yet with MTBs we’ve seen a shift to much more stable slower steering behaviour. Why is that a good thing on a MTB but a bad thing on a road bike?
(edit - as posted above as I was typing - ) Arguably a modern LLS MTB isn't much better (as good as?) an early 90s XC bike on twisty lower-tech singletrack and early 90s MTBs were still developing, the era when MTBs were designed by a lot of roadies with low fronts, long stems and steeper angles. Anyway, roads aren't that twisty as you say but a road bike works well when you can corner hard from close to the seated pedalling position. You pedal along, lean into the corner and pedal out, repeat. Cornering an MTB is far more active and dynamic. No reason for a road bike not to use that off-saddle, body adjusted committed cornering technique but the all-road bikes I've had that can benefit from that still get a bit wearing to ride on road. eg the PvD bike (which is an all-roader and prob a riot on loose gravel) will be amazing on some roads if you ride it like a mountain bike. But on a longer road ride that's not what I'd want. And cornering on an MTB is partly about the edge of grip and how to push it and you don't want to / can't do that on road. Slide a tyre and you're down.
That's one big difference - steering methods, geometry, all around how an MTB is designed to handle sliding tyre/s. On a road bike you have huge amounts of grip (in the dry) and you really don't want to lose that at either end. The way you corner them (road bike is a lean with minimal bar steer and reliant on the short wheelbase for tighter turns vs MTBs from-hips / opposite lock tendency, potentially lot of bar steering to force a longer wheelbase round and slide where needed), the weight distribution, need for aerodynamics and efficient pedalling, etc. They're polar opposites in every area I can think of that would affect steering geo or general design?
What is the fundamental difference in how you ride the bike
So I'd say it's the way we interact with the bike as they're cornered, which is fundamental to a bike's design brief.
Relativity is an odd thing.
This is a really valid point. I make a point of jumping on my road bike straight after a 2 week loaded tour on my fat-tyred all-roader, or onto the all-roader after a longer period of just riding the MTB, since the adaptation to one bike makes some aspects of another stand out. The best bikes seem to also be ones that are natural and fast to adapt to from a muscle memory of something quite different. I do think what we talk about in these threads is as much feedback loops, preferences and muscle memory as the design and handling tech we think it is. Good geek-out topics..
Now I’m looking for a bike that can do a bit of road and a bit of trail and find myself questioning why gravel bikes seem to mainly adopt road geometry. Not saying it is wrong, just questioning.
In short, gravel bikes are simply fatter-tyres road bikes with a slight geometry adjustment to suit comfort and easy off-road terrain - though they still behave much like road (or CX) bikes in most ways. That's right imo, as any light drop bar bike should be capable of making a good road bike esp with some 28mm tyres on.
It’s funny thou the subtle change in a bike and the perception feel.
I have a fancy gravel bike for fun and it’s Chinese clone for commuting duties, the geometries and setup are the same on both but the commuter has a narrower width version of the handlebars and feels so much better although the usual sizing guidelines would edge towards a larger width in relation to shoulder width.
Yes, I guess that’s the sort of thing I had in mind when I started this thread. Not so sure now I’ve seen it though 🙂
(image via LFGSS)
