How much of a difference will I notice going from a Mountain bike to a road bike?

• You will find the journey a lot less effort, as you are dramatically reducing the weight of the bike.
• You will also be able to accelerate much faster, as the rolling resistance will be reduced through the use of thinner tyres.
• Your gearing is likely to allow for faster speeds as well.
• If you previously had suspension, you will notice the ability to accelerate, brake and turn is much better, and more precise.
• You will rapidly learn how uncomfortable bumps are so you will have to get used to dodging round stones, potholes etc.

A lot.

But before you go out and buy anything shiny and new, why not try a short term investment in some 26" Conti Gatorskins at 1.25" for your mtb? (You'll probably need a new pair of innertubes as well) Try commuting on these and I bet you'll notice a big improvement on 1.95" tyres, just by making this relatively inexpensive change.

(Then go out and spend a few thousand dollars on a carbon road bike and it'll be better still!)

You will notice 3 major differences right away, with other difference you can optionally implement in the future.

1. Road bikes gernally are much lighter than mountain bikes. Less weight means you can go further or faster with the same amount of effort you put into your mountain bike.
2. Road bikes have much narrower tires (compared to a mountain bike) with much higher pressure. This means you have much less rolling resistance on a road bike. Once again, you can go further or faster with the same amount of effort you put into your mountain bike.
3. Your riding position on a road bike is much more aerodynamic than it is on a mountain bike. Thus you can go further or faster with the same amount of effort you put into your mountain bike.

Those are the stock differences. Optionally you can:

1. Add toe clips or cleated pedals to your bike. Locking your foot to the pedal increases the efficiency of your biking. This can make it another 10% easier to ride your road bike.
2. Add aero bars- if you bike in the wind often, or ride fairly fast, adding aero bars gives you an additional biking position with lower wind resistance. This can make it another 10% easier to ride your road bike.

How much difference, you asked. When I started to ride skinny tires, I noticed the far places, the ones I took too long to reach, became very close and I could get there fast with way less effort. It's like distance and time were distorted to my favor, like StarWars time travel.

The downside, as already said: it seems like you spent too much time fighting boxe with padded protections, then suddenly you are bare-hands and bare-face, flying at 35+ mph around treacherous obstacles you can no longer ignore, balancing over a twitchier, harsher handlebar where brake levers are not reachable all the time. Anyway, it's impressive how much abuse a 23mm tire can endure if the rims are solid.

After the novelty passes, though, one ends up knowing, respecting and admiring strengths and weaknesses of either bike type, also being able to assemble, if wanted, a whole colorful range of possible hybrid setups, or even using either type of bike outside its expected primary application.

Hope this helps!

The difference is HUGE! When you get on a set of skinny, hard, fast rolling, knob-less road tires, it will feel like your bicycle has been set free. The knobs on a low pressure mountain bike tire create and enormous amount of drag, when you no longer have to push against them the difference will be unbelievable.

You may also notice you are no longer riding with your chest stuck out like a sail. You will find the new, sleeker, aerodynamic profile allows you to maintain your speed with much less effort.

You will also notice the ride on the skinnier, harder, road bike tires is much rougher going over bumps and potholes. This drawback is well worth not having the drag. You may compromise by getting a fatter tire than allows for lower air pressure and gives you more cushion but I prefer the reduced drag hard and skinny tires give you.

You will probably notice the road bike is lighter and with your lighter bike and less tire drag it is much easier to accelerate on.

Going up steep hills you will probably notice the gearing on the road bike is higher and may miss the lower gearing unless you road bike is equipped with a touring gearing (3rd smaller inner ring).

You will probably not notice the lack of tread, even on gravel bike trails. For the most most part the tread is not necessary on gravel bike paths but if you corner hard in gravel you will notice that your wheels wash out much easier, so take extra care when cornering.

If it's a traditional road racing type setup, you will notice the handlebar and braking setup is different and that it's even a little harder to stop. At first you will also find shifting is a bit confusing and may take a little time to get used to.

You may also find your riding position is a little less natural and a little less comfortable.

Get a road/commuter specific bike. You wont regret it.

Over the years I've used both and in my opinion hard tail MTB with 1.25 inch slicks or a hybrid is the way to go. What you lose in top speed you gain in durability. MTB is far better equipped to take the punishment of daily commute. There's nothing more annoying than changing tubes or sorting tangled chains when you should already be at work.

A set of hill climb / bar ends makes a huge difference and allows you to adjust riding position. If you need extra speed, get a set of riding shoes with cleats or just old school toe clips.

In regards to the speed it really depends on the rider as much as it depends on the bike. I do frequently 30 to 50 miles social rides on the weekend and and I keep up on my 26" MTB. The only times I'm in real disadvantage is long gently sloping downhills where I simply don't have high enough gears.

Instead of a road-bike for commuting, you could consider a "hybrid" bike that's intended specifically for commuting: see for example this question and this answer.

My commute is in traffic, so a lot of starting and stopping, and, all-weather riding: so flatter (instead of dropped) handlebars, disk brakes (useful in rain), mudguards, a rack and pannier, and other things you wouldn't find on a road bike.

A hybrid will give many of the same speed advantages, e.g. no suspension, non-knobbly tires, and an adequate range of gears.

I have now had a road bike for 3 days since i transferred from mountain biker to road biker. I've done just over 50 miles and my experiences so far would be both bikes have pros and cons. The mountain bike is a LOT slower. The width of the tyres being thicker means more surface contact with the road and it slows you down and requires way more effort to ride especially uphill. The road bike i have, has thin tyres and the speed difference is amazing. The only drawback i have found is that without a suspension, you really feel every tiny bump/divot in the road and on long rides this can become very uncomfortable in your back/lower body/arms.The mountain bike protects you much more. Your body position too needs getting used to. Leaning forward rather than sitting up straight is a bit weird but again, i'll get used to that. Overall though i'll be sticking to the road bike, you'll love the speed difference.

This is an old thread, but maybe my answer will help someone.

I walked into a bike shop yesterday thinking I would get a MTB or hybrid. I have always ridden them and in France where I rode a lot in town, that was necessary: there were hardly any bike roads and I would get up and off the side walk constantly, crossing tramway tracks and navigating obstacles. A mountain bike is good for that, you can stand on it, slalom anywhere, stop and go with little effort/awkardness. With a mountain/hybrid bike, you are "in" the bike, it becomes part of you and it protects you.

However, the guy in the shop was having none of that and made me get onto a road bike, ahhh!! I felt uncomfortable and a bit scared as he held it and made me pedal backwards and adjust my position. I still agreed to take it for a test ride around the block but was actually a bit relieved that he handed me a helmet... I normally never bother with helmets.

Anyway, so here I was, getting not into my usual position in the bike but instead perching myself onto that narrow frame. Starting the bike was awkward, but the moment I got going it felt wonderful. I was flying over the road with an ease I had never known. I only enjoyed the feeling for a second though: the brakes, where were the brakes? I needed my brakes at their usual position. Slightly panicked, I pressed the brakes and found that I could stop, but not as abruptly as on a mountain bike. The days of racing down a super narrow street at full speed and hitting the brakes as hard as they would go at the very last second were over... then again, there are not so many narrow streets in the US.

I found that navigating traffic at a red light was uncomfortable and wondered if I could get used to the bike, so I said I wanted to take the hybrid MTB type bike that I had been eyeing. Getting on it was bliss, it was so easy and familiar. However, the moment I hit the road, I started missing that feeling I had had with the road bike, that feeling that I was flying over the road. I got up on the bike, slalomed, braking hard and starting again, finding some satisfaction in my antics.

If the MTB had been really great, I might even have bought it, but it just wasn't that good. It was an alright bicycle and would do, but I wouldn't love it. I went back to the shop and took the road bike again. The second time felt less awkward, and I was flying over the road again.

I bought the road bike and am very happy with it. One disadvantage for me is that I can't pack it the way I used to pack my old bike. I used to have a big basket it the front and a large rack with two baskets in the back. I would go to Home Depot, but tools, planks, tiki torches, etc, and then pass al the hopeful drivers with their vans, put everything on the bike and drive away, leaving them baffled. The more weight I put on my bike, the more stable it would get and even though it make the bike heavier, the effort to get it moving never got insurmountable.

On my new bike, transporting that much stuff would be unthinkable. Guess the van drivers will love my bike ;)

Put it this way - when I go back to riding an MTB after riding a road bike, it feels like the cycling equivalent of swimming through treacle.

This old question made its way to the top of the pile, and I found that in 2018, most of the answers are incorrect.

As it stands now, a road bike is indeed faster, but the margins are not 'huge' or 'a lot' as described in the other answers, but range from small to negligible depending on the size(bigger riders make more power) and fitness of the rider and quality of tyres chosen. Since this question was first asked typical MTB wheel sizes have increased with 29ers being common (larger wheels roll faster). MTB tyres have also progressed a lot, and there are now excellent supple tubeless tyres available with high tech compounds that roll fantastically well.

For me, the difference between a 29er with a quality XC tyre and a road bike with quality tyres is around 2mph. However replace that XC tyre with a quality touring/gravel tyre and that drops to ~1.5mph. However on the road bike, the difference between an entry level tyre and a quality tyre is also in the region of ~1.5mph. Add in some poor/coarse road surfaces, and the gap between the two bikes narrows even further.

So in summary tyres play the biggest role at typical commuting speeds, and a MTB fitted with a high quality slick tyre could even be faster than a road bike with a poor quality tyre.

Let's compile a list of the best reasonable looking experiments we can find (single rider on both bikes in same route at the very least).

These appear to be on relatively flat good tarmac and results were measured with Strava:

17 mi flat

• MTB 15.7 mi/h avg 427 cals
• road: 17.6 mi/h avg 413 cals

9.2 mi 320 ft elevation. Not sure why he was so slow on both:

• MTB: 10.2 mi/h avg 588 cals
• road: 13.5 mi/h avg 399 cals

How do on-road mountain bike speeds translate to road bike speeds?

• road about 7km/h faster on flat
• climb was slower, but he didn't have as low gears on the road bike, so we can't really compare

Related: Will changing from a touring bike to a racing bike improve my energy level?