MPH difference - MTB vs Road bike

At least 1.5 times as fast, with the same effort, or even less effort. The few times I ride my mountain bike on the road I average about 20 km/hr. With the road bike I can easily do 32-33 and feel like I'm not working as much.

I do not agree with this. If you have a nice mtb with fixed forks, it rides really well. With 2" tyres you have a handicap, but with narrow slicks on it, very small handicap. Proof for this is "vättern rundan" in Sweden. It is a race round the second biggest lake in sweden. It is around 310-320 km. I think it is the biggest race in sweden, thousands of people in it. Maybe even up to 10 000 people riding it. It has a proper "elite" class, with the national elite of Sweden in it. An ex pro cyclist swedish, can not remember who it was, rode it on an MTB and finished high, top 5 I think, some years ago. If it had a 10% "deficit" that would just not have happened I think.

I used to have a Kona Explosif with fixed forks many years ago. With knobblies on it, over say 20 K, I think I gave up lot less than 5 km/h compared to my road bike. Not a very scientific test but hey. 🙂

I've a Giant XTC Hardtail with rigid fork 1.25" Panaracer slick, bike weight 20lbs and a giant TCR weight 17lbs, I can tell you they're differences. If for town start stop traffic use the hardtail is better and easier on your legs, if for anything more than 50km you can feel you use much less energy on the roadbike.

In no way they're equal.

I sometimes commute to/from work on either my road bike with 23mm slicks, or the mountain bike with 2" semislicks.

The road bike is about 10% faster on average. (With the roadie it usually takes 48-49 minutes, on the mountain bike 52-54.)

You can go for longer, easier on the road bike though.

Bob Roll won a road race in the San Francisco area a few years back on a MTB. Don't quite remember which one, just remember hearing about it. The other riders were a bit put off and felt it was cockiness/arrogance.

I think the key though is having high-PSI, narrow road tires and fixed forks. I rode a Bridgestone MB zip for years with speciallized fat boys (100 psi slicks) on the roads. I'd say it's easily within ~10% of my roadbike on hills, but more like ~20% on flats (where you just can't get as aero). Suspention forks would blow that up though.

I'm sure that some riders are capable of posting excelent times racing and riding on MTB's -- times that are comparable to what the rest of us do on RB's. That said, I think the average rider probably would notice an immediate increase in speed moving from MTB to RB. I'm not sure how to quantify the increase (percentage, etc.), but it was very noticable for me when I switched from MTB to RB.

An MTB handles very differently from an RB. Many RB's are designed to carve long, straight lines at peak efficiency and high speed. Many MTB's make concessions to efficiency and speed in the interest of maneuverability, shock absorption, etc. From a design standpoint, it seems as though the difference would be fairly evident: you should have a faster, more efficient ride on a bike that is designed (frame geometry, tire width, weight, components) to maximize your speed rather than your handling.

That said, RB's are not hard to handle or maneuver, and MTB's are not clunky and slow. There are differences, and as always, preferences. Ride what you like and enjoy it. It's hard to go wrong if you follow that route.

Cheers.

Thanks for your replies. I'm 40 years old, still about 25 pounds overweight (after already losing about 35 pounds), and haven't done any serious riding in years. I'm working on shedding the rest of that weight and eventually training to take a century ride. My mtb is a low-end Schwinn with suspension forks purchased at Wal-mart. From what some of you have posted (and as I expected), I think I'd be noticeably better off if I switch to a decent road machine.

mmmmm... maybe we should ask LA to ride a MTB on his next tour?

Of course it matters how aero you sit on your bike. I had a very aggresive postion on my MTB. It goes without saying that you will be slower with a situp and beg position. If you have a good position on your MTB, the differences are not that big. As already stated here, people win day races on them.

On long distances, I noticed that the seating position on a mtb was more exhausting. Otherwise, differences weren't that great, especially if lightweight slicks were on the mtb.

Remember that the TDF runs for over 80 hours of riding, but 5 minutes is a typical margain of victory, so small differences are the name of the game.

Shreklookalike said:

I've currently got a mountain bike with road tires for commuting/fitness. I figure I'm averaging in the 10 to 12 mph range (based on approx. distance traveled in approx. 1 hour -- no computer, odometer or reliable watch used). For those of you who have both types of bikes, what kind of difference in MPH should I expect if moving from a mountain bike with 2" road tires to a road bike?

race bike on 23mm tyres v mtb on 1·5 inch semi-slicks : down hill about 10 - 15 kph ( coasting ) depending on slope , 40 kph start speed
fastest on MTB = 58 kph
fastest on race bike = 67 kph ( breaking early - more brains than balls these days ) 🙄

tyre pressures 110 psi and 65 psi .

Remeber that your top gear is a lot lower on the MTB

I`ve never tried a real roadbike, but I`ve tried some MTBs and all I can say is that tyres are what slows (or vice-versa) you down mostly. I've ride a bike with wide and very rugged tyres (dont remember the size) which are ment only for mud and sand on asphalt. You can actually hear how they slow you down. It's the sound from tyre and asphalt contact points. Shocks will not bother you if you're sitting still and just pedalling. If you stand straight on your legs and pedal - shocks will drain the speed.

Claes said:

Remeber that your top gear is a lot lower on the MTB

Is it ? 44/11 x 26 = 104 inches
52/13 x 27 = 108 inches

This is the old English system and is based around the old penny farthing where the diameter of the wheel was the gear , it´s a bit rough and ready but it gives an easy answer that means more than yards or meters will .

eg 52/13 x 2115 mm = 8·46 mts accurate ( well sort of ) but difficult to use in compairing one gear with another .

el Inglés said:

Is it ? 44/11 x 26 = 104 inches
52/13 x 27 = 108 inches

This is the old English system and is based around the old penny farthing where the diameter of the wheel was the gear , it´s a bit rough and ready but it gives an easy answer that means more than yards or meters will .

eg 52/13 x 2115 mm = 8·46 mts accurate ( well sort of ) but difficult to use in compairing one gear with another .

That is a lot closer than I thougt, but for good measure I think most road bikes these days has a 53, and a 12 at the rear this gives 119 inches top then? So, it is a quite big difference. 🙂

never did the stats before but on my old mtb to top gear got used a lot on the road, that does not happen with the road bike as much.

Ever figure out how many times you have to spin a 26" wheel compared to a 700c- I did the math for my wife and came up with 1000+ times a mile (I can't remember exactly what it was)...anyway, that is a start...

If you are as out of shape as you said- I say your an animal! 10-14 is pretty good on an mtb- I periodically ride mine (with 1.6 slicks) and get that...now on the roadie- I get 20's with what I feel is a third the effort, probably half though. Thats leisure riding though- and I can get it going a lot faster if needed. Anyway- the roasdie ain't really about speed- it is about effort vs achievment for me- less effort for more distance, like a balanced engine really.
Cheers

Shreklookalike said:

Thanks for your replies. I'm 40 years old, still about 25 pounds overweight (after already losing about 35 pounds), and haven't done any serious riding in years. I'm working on shedding the rest of that weight and eventually training to take a century ride. My mtb is a low-end Schwinn with suspension forks purchased at Wal-mart. From what some of you have posted (and as I expected), I think I'd be noticeably better off if I switch to a decent road machine.

For trips 22 miles or less my $300 Trek MTB is working well and I am not in a rush to get a road bike. I would probably get a cycle cross bike when that day comes they seem a little tougher than road bikes.

What is the top speed difference between MTB and RB if any I can only reach 28 mph on MTB with knobbys While on a flat paved old railroad bed turned bike trail and don't have a RB yet are there any experimenters out there? My buddy had a cycle cross bike on the trail and only did 29mph but we may not be equally fit.