How much faster is a gravel bike than MTB
Discussion
I compete in off road duathlons on forest fire tracks. There are occasional roots and ruts but mostly straight on gravel. Clearly gravel bike territory.
I currently use an ancient 90's mountain bike which is showing it's age.
I had assumed I'd update to a gravel bike and started a thread about it on here some months ago. (Buying new car lead to delay) In that that thread it was suggested a modern MTB might be nearly as good. From my point of view it would be better for everything else I do on bikes so now I'm in a quandary.
How much faster is a £1200 (before C2W) gravel than a similar priced MTB? What do I look for for a fast version of either?
Thanks
I currently use an ancient 90's mountain bike which is showing it's age.
I had assumed I'd update to a gravel bike and started a thread about it on here some months ago. (Buying new car lead to delay) In that that thread it was suggested a modern MTB might be nearly as good. From my point of view it would be better for everything else I do on bikes so now I'm in a quandary.
How much faster is a £1200 (before C2W) gravel than a similar priced MTB? What do I look for for a fast version of either?
Thanks
Probably not much difference between a gravel bike on 700c 40mm tyres and a 29" xc hardtail.
Mainly depends on the fitness of the rider. 700c wheels roll smoother than old 26" wheels, and a gravel bike is likely to be lighter than a MTB. Gravel bike faster on road due to more aero position (depends how fast your going though) and gearing. MTB better over bumpy surfaces though.
"Gravel" is a bit of a spectrum though, from what are basically road bikes with clearance for 32mm tyres at one end, to heavy bike packing type bikes at the other. You can get rigid MTBs that are essentially flat bar gravel bikes, and gravel bikes with suspension. Just comes down to preference at the end of the day- do you want flat or drop bars and will you be doing much road riding?
Mainly depends on the fitness of the rider. 700c wheels roll smoother than old 26" wheels, and a gravel bike is likely to be lighter than a MTB. Gravel bike faster on road due to more aero position (depends how fast your going though) and gearing. MTB better over bumpy surfaces though.
"Gravel" is a bit of a spectrum though, from what are basically road bikes with clearance for 32mm tyres at one end, to heavy bike packing type bikes at the other. You can get rigid MTBs that are essentially flat bar gravel bikes, and gravel bikes with suspension. Just comes down to preference at the end of the day- do you want flat or drop bars and will you be doing much road riding?
I’ve got both and the main two factors making the gravel faster are the more aggressive geo making you more aero, the lower rolling resistance of the tyres and the added efficiency from it being a rigid frame. All that applies to a budget gravel bike so even a £1000 entry bike will still see off a mtb on the correct terrain.
Emphasis on the correct terrain though. As soon as it gets technical, very bumpy, clarty mud etc.. all that lovely gravel bike stuff works against you and the mtb is simply faster as mtbs are designed for this type of riding.
As for what to look for in a gravel bike. Hydraulic brakes as upgrading cables to hydraulic later down the line is costly. 1x drive train if you’re mostly off road, or 2x if you wanna chase down roadies. Then put a good set of tubeless gravel tyres on it as those are your only suspension.
Emphasis on the correct terrain though. As soon as it gets technical, very bumpy, clarty mud etc.. all that lovely gravel bike stuff works against you and the mtb is simply faster as mtbs are designed for this type of riding.
As for what to look for in a gravel bike. Hydraulic brakes as upgrading cables to hydraulic later down the line is costly. 1x drive train if you’re mostly off road, or 2x if you wanna chase down roadies. Then put a good set of tubeless gravel tyres on it as those are your only suspension.
There is quite a difference between the two bikes, as I have both.
Both are carbon and both are 2x.
The gearing of the gravel bike and the geometry/slightly faster rolling tyres allow it to be faster. Obviously on much rougher/muddier stuff the hardtail can hold its line easier. But overall, a gravel bike with 40+mm tyres is a very quick bike and can zip along tarmac quickly too.
I have also used my hardtail in 2 stages of gravel racing last year, but found it to be slower against gravel bikes despite riding it quickly as I could.
Both are carbon and both are 2x.
The gearing of the gravel bike and the geometry/slightly faster rolling tyres allow it to be faster. Obviously on much rougher/muddier stuff the hardtail can hold its line easier. But overall, a gravel bike with 40+mm tyres is a very quick bike and can zip along tarmac quickly too.
I have also used my hardtail in 2 stages of gravel racing last year, but found it to be slower against gravel bikes despite riding it quickly as I could.
Wife has a gravel bike, it's extra small, - took it for one lap of local park (30mins, flat, gravel) which I ride a couple times a week on hardtail and full sus 27.5 bike (and I ride a large size).
Got my second best time ever on the lap even though it felt like I was riding a BMX - knees hitting the bars and didn't feel like I wasn't pushing that hard - felt very quick.
Power delivery is like a road bike on flat gravel, MTBs flex more even fully locked out. Would be different on rough, rooty ground though.
On the gravel bike she is above to keep up with me on flatter terrain when I'm on MTB and there is a big difference (60ish) in our ftps. Much easier to cruise at 20kmh+ speeds on it (some of that's tyres but also wind resistance ramps up from there).
Got my second best time ever on the lap even though it felt like I was riding a BMX - knees hitting the bars and didn't feel like I wasn't pushing that hard - felt very quick.
Power delivery is like a road bike on flat gravel, MTBs flex more even fully locked out. Would be different on rough, rooty ground though.
On the gravel bike she is above to keep up with me on flatter terrain when I'm on MTB and there is a big difference (60ish) in our ftps. Much easier to cruise at 20kmh+ speeds on it (some of that's tyres but also wind resistance ramps up from there).
leyorkie said:
Basic gearing. Fit a gravel group set to your MTB and it would be as fast on the flat.
A 40x11 compared to a 32x11 will be quicker assuming a 1x12 set up. But then you loose your climbing gears.
You'll need an engine strong enough to max out the top end on each bikes gearing.A 40x11 compared to a 32x11 will be quicker assuming a 1x12 set up. But then you loose your climbing gears.
You’ll be able to upgrade your ancient 90s MTB into something a bit faster for considerably less than £1200.
I built up this ‘gravel bike’ from a £25 frame from stuff i had in the parts bin:
^ that’s running 700c wheels so not the same as your MTB.
Converting a 26” MTB to drop handlebars is fairly simple as long as you get drop bars in MTB diameter: 25.4mm at the clamp, 22.2mm at the grip.
Another option that’s a bit cheaper would be to pick up (say) a Carrera cyclocross bike on Gumtree or similar. Don’t worry if it has cantilever brakes, it’ll still stop. £300 should see you on something serviceable. This is £120:
I built up this ‘gravel bike’ from a £25 frame from stuff i had in the parts bin:
^ that’s running 700c wheels so not the same as your MTB.
Converting a 26” MTB to drop handlebars is fairly simple as long as you get drop bars in MTB diameter: 25.4mm at the clamp, 22.2mm at the grip.
Another option that’s a bit cheaper would be to pick up (say) a Carrera cyclocross bike on Gumtree or similar. Don’t worry if it has cantilever brakes, it’ll still stop. £300 should see you on something serviceable. This is £120:
leyorkie said:
Basic gearing. Fit a gravel group set to your MTB and it would be as fast on the flat.
A 40x11 compared to a 32x11 will be quicker assuming a 1x12 set up. But then you loose your climbing gears.
Technically yes but the amount of power to do say 20MPH on the MTB will be significantly higher than that on the gravel bike. A 40x11 compared to a 32x11 will be quicker assuming a 1x12 set up. But then you loose your climbing gears.
There is probably not much more than 1.5KG between my gravel bike and MTB but watt for watt the gravel bike is much quicker. On a 40 mile ride with a 3000ft of elevation and around 25 miles of hardpack or tarmac the average speed on the gravel bike is usually around 1.5-2mph higher. That's a significant difference. The only place the MTB is quicker is downhill on the gnarly off-road segments.
However despite this difference I prefer to ride the MTB on these routes just for the comfort.
I've just had a look back at an old favourite Strava segment of mine. It's called 'Grim duathlon 2014 lap'... https://www.strava.com/segments/8455630?filter=ove...
I'm only 10 seconds down on the KOM for the segment at the moment. I didn't ride the actual race, but sought out the segment later because it's a good test off road at over 5 miles per lap, and it used to be very local for me. I had a look at my ten fastest attempts on the lap, and found I was fastest on my Trek Emonda road bike. Second fastest on my Giant Anthem full sus MTB, third fastest on the Emonda again, fourth fastest on the Anthem, and fifth fastest on a "sort of gravel" Frankenbike of a Cannondale Backroads which was converted from a flat bar gravel hybrid built for the American market. The next five fastest times were all on the Anthem MTB though. Take a look at this Strava activity... https://www.strava.com/activities/1574416010#62246... ...for three photos (ignore the lakeside ones) of parts of that segment, and bear in mind that my Emonda is a rim-braked pure road bike with stated maximum tyre clearance of 25 mm. Bear in mind, too, that I only rode that segment with speed in mind. It was never something I rode (and I rode it 56 times) to just chill out around. If I wanted to take it easy there were far more picturesque trails to ride. Sure, there were some slower times on it, but mostly due to poor weather and trail conditions, or gorse clearance with tractors and machinery ruining the flow and churning up the trail. Weather and trail conditions affect bike choice too. A hot, dry summer on that segment played right into the hands of my road bike, but a soggy spell would make it unrideable on 700 x 25c slicks. A gravel bike could cope with both wet and dry conditions.
I aim to buy myself a modern gravel bike this year, and so i'd love to take it back to my old stomping ground, and if I can remember 5 miles worth of twists and turns, see how it compares on that old segment. There are heaps more Strava segments in that area that would suit a gravel bike too. Some of which I had a long, drawn out rivalry on with a chap who ended up becoming a friend. I'd like to surprise him with some fresh gravel bike "firepower" on a few of our old competitive segments and see if I can't leapfrog him on some of those leaderboards.
To answer the question "how much faster is a gravel bike than a MTB?" I suspect that if you compared the two bikes on terrain most suited to the gravel bike, it would be significantly faster on a gravel bike than a MTB on the same course with the same rider. If I can out-ride myself on a road bike on a gravelly heathland common compared to a pretty decent XC MTB, then there's no way I believe I'm going to be slower on a gravel bike. It just wouldn't make sense, even being in my mid 50s now and not my late 40s anymore.
I'm only 10 seconds down on the KOM for the segment at the moment. I didn't ride the actual race, but sought out the segment later because it's a good test off road at over 5 miles per lap, and it used to be very local for me. I had a look at my ten fastest attempts on the lap, and found I was fastest on my Trek Emonda road bike. Second fastest on my Giant Anthem full sus MTB, third fastest on the Emonda again, fourth fastest on the Anthem, and fifth fastest on a "sort of gravel" Frankenbike of a Cannondale Backroads which was converted from a flat bar gravel hybrid built for the American market. The next five fastest times were all on the Anthem MTB though. Take a look at this Strava activity... https://www.strava.com/activities/1574416010#62246... ...for three photos (ignore the lakeside ones) of parts of that segment, and bear in mind that my Emonda is a rim-braked pure road bike with stated maximum tyre clearance of 25 mm. Bear in mind, too, that I only rode that segment with speed in mind. It was never something I rode (and I rode it 56 times) to just chill out around. If I wanted to take it easy there were far more picturesque trails to ride. Sure, there were some slower times on it, but mostly due to poor weather and trail conditions, or gorse clearance with tractors and machinery ruining the flow and churning up the trail. Weather and trail conditions affect bike choice too. A hot, dry summer on that segment played right into the hands of my road bike, but a soggy spell would make it unrideable on 700 x 25c slicks. A gravel bike could cope with both wet and dry conditions.
I aim to buy myself a modern gravel bike this year, and so i'd love to take it back to my old stomping ground, and if I can remember 5 miles worth of twists and turns, see how it compares on that old segment. There are heaps more Strava segments in that area that would suit a gravel bike too. Some of which I had a long, drawn out rivalry on with a chap who ended up becoming a friend. I'd like to surprise him with some fresh gravel bike "firepower" on a few of our old competitive segments and see if I can't leapfrog him on some of those leaderboards.
To answer the question "how much faster is a gravel bike than a MTB?" I suspect that if you compared the two bikes on terrain most suited to the gravel bike, it would be significantly faster on a gravel bike than a MTB on the same course with the same rider. If I can out-ride myself on a road bike on a gravelly heathland common compared to a pretty decent XC MTB, then there's no way I believe I'm going to be slower on a gravel bike. It just wouldn't make sense, even being in my mid 50s now and not my late 40s anymore.
Significantly. I've a 650b carbon MTB and a Carbon Gravel bike. Over a km segment, flat grass and gravel I'm about a minute faster. 2.08 Vs 3.09. It's night and day. Throw tarmac into the equation and it's even more dramatic. My average speed on MTB is 10mph, gravel about 14mph or more.
helix402 said:
It depends on the circumstances. I could get over 50mph downhill on the road on my old Stumpjumper. My new Diverge, I can’t even do 40 due to the low gearing. On a long road ride though my average speed might be higher on the Diverge.
What's the biggest gear on the diverge? Surely you just need a 20% straight road and get in a tuck. 
It's an apples to oranges comparison. Each will have strengths and weaknesses in different areas. Could argue a gravel bike is basically the same geometry as an early old school mtb though. You could spec either type of bike to be pretty close with the right parts.
Tyres and gearing will make all the difference. I went out riding with the father in law; him on a sonder camino ti (same/similar gearing as your last post) me on a 34t front and 10-51t rear casette, 150mm travel front sus hardtail 29er. He had somewhere between 35-40mm tyres, I had 2.4 inch back 2.5 inch front. On downhills or flat open roads i was spinning out trying to keep up. On hills or even remotely bumpy stuff I left him for dead.
Personally I think 1x gravel bikes aren't flexible enough gear wise and basically exist to fulfill the n+1 rule for bike fans and manufacturers. They're a sort of middle ground that don't give you the faster road gears or the lower mtb gears. Probably off-trend but a high end 2x cross country mountain bike will probably be faster and more comfortable everywhere.
Tyres and gearing will make all the difference. I went out riding with the father in law; him on a sonder camino ti (same/similar gearing as your last post) me on a 34t front and 10-51t rear casette, 150mm travel front sus hardtail 29er. He had somewhere between 35-40mm tyres, I had 2.4 inch back 2.5 inch front. On downhills or flat open roads i was spinning out trying to keep up. On hills or even remotely bumpy stuff I left him for dead.
Personally I think 1x gravel bikes aren't flexible enough gear wise and basically exist to fulfill the n+1 rule for bike fans and manufacturers. They're a sort of middle ground that don't give you the faster road gears or the lower mtb gears. Probably off-trend but a high end 2x cross country mountain bike will probably be faster and more comfortable everywhere.
I think you’re probably right in your last sentence. I changed to a gravel bike as I moved to an area with limited local off road routes. I fancied a change and couldn’t face the move to a road bike. I only have one bike.
The mountain bike was certainly more comfortable. I’ve enjoyed the gravel bike though. Did King Alfred’s Way last year in 3 days and the North Down’s Way this year. When my drive train wears out I’ll look to change the gearing to give a higher top gear.
The mountain bike was certainly more comfortable. I’ve enjoyed the gravel bike though. Did King Alfred’s Way last year in 3 days and the North Down’s Way this year. When my drive train wears out I’ll look to change the gearing to give a higher top gear.
Anecdotal story for you. My mates all bought gravel or cross bikes a few years ago, I'm stuck on a 15 year old hardtail mtb, triple chainset, pretty upright frame. This is good when you are on the right terrain, such as up on the South Downs, which is where we used to ride, but gradually the routes changed. Less climbing, a bit more actual road, a bit of unmade road, a farm track, a stretch in the woods. At first we carried on riding together, but after a several rides on this mixed terrain, I stopped. I just couldn't keep up, and it was no fun having to thrash myself just to keep them in the sight.
I'm lucky enough to live right on the edge of the Downs so can go for hours on proper rough & variable technical terrain, constantly up or down. I don't mind if my average speed is 10-12 kmh.
I'm lucky enough to live right on the edge of the Downs so can go for hours on proper rough & variable technical terrain, constantly up or down. I don't mind if my average speed is 10-12 kmh.
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