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Speed difference between a mountain bike and a road bike....(7 posts)

Speed difference between a mountain bike and a road bike....kylebike
Sep 13, 2002 1:26 PM
I am currently training with a mountain bike on the road and have not yet purchased a road bike. I plan on entering some races in the fall.
My question much faster can I go using a road bike?? Would it put on an extra 5km/hr? 10km/hr??? more??

My analogy:shirt
Sep 13, 2002 2:47 PM
Riding a mtb in a road situation is like packing 35 extra pounds of body fat.
I would listen to Shirtallervite
Sep 13, 2002 8:06 PM
He is speaking from experience. I believe that is how much weight he gains in the winter. ;)
re: Speed difference between a mountain bike and a road bike....BenD
Sep 14, 2002 6:45 AM
I was in your situation earlier this summer, and I ended up buying a road bike in June. I can't tell you how much of a difference you will notice without knowing what you are currently riding and what you are planning on buying. I can only tell you my experience.

I had an old Al bike w/o a front suspension with 1.6 inch semi-slick tires. I bought a used carbon fiber bike with full ultegra and open pro rims. Even though I love my new bike and have never once regretted the upgrade, I was dissapointed by the small increase in average speed of 1-3 miles/h since everyone I spoke to told me to expect 4-5 mph difference. Maybe you could expect this kind of difference if you had a front suspension and knobby tires.

You will however, notice a huge difference when climbing and accelerating, but I don't think the decrease in weight and thinner tires really help that much on the flats where the wind provides most of the resistance.

Despite what I have said, buy one. You won't regret it.
re: Speed difference between a mountain bike and a road bike....BakovDevils
Sep 15, 2002 9:51 AM
I fully agree with 1 - 3 miles/h difference, however, count rather with 1 - 2 miles/h. If you go for climbs, it will be even less. My own experince - no bike can replace you legs, lungs.... ;)
Fast Vs Scary Fast ...breck
Sep 17, 2002 2:25 PM
A properly set up MTB has poor aerodynamics for speed. Too high a stem angle, too wide a bar, too wide a bottom bracket due to the need for a triple crank. And too heavy a tire. Also the head tube angle is rather relaxed, so it's slower in the steep down hill tight scary fast curves. You can fix the stem, bar, tires, and maybe even the BB, but not the head tube angle.

For laughs, say the delta speed was only 3 mph. Besides being behind 15 miles at the 5 hour point you would have spent more energy getting there.

Cheers all,
Klein MTB ............... fast
Trek OCLV road .... scary fast :)
I doing the same thingAmbishawn
Sep 29, 2002 12:13 PM
I'm currently using My Mountain Bike for road and mountain rides. I basicly swap out the tires useing Specialized fatboys with 100psi when useing the bike on the road. I also have an air suspension fork which I run 55psi on road and 37psi off. (Marzzocci Z1 Xfly). I noticed an average increase of 2 MPH on the flats with the installation of the fatboy tires. I ride road 50-60 miles on sunday and two 20 mile rides durring the week. I feel the biggest slow downs are the lack of drop bar, slightly longer 175mm cranks with more seat set back vs. 172.5 cranks recommended by professional bike fitting seasion involving Serrotta size cycle, and the gearing for the down hills. My mountain bike has compact gearing compaired to the 53 to 11 or 12 possible with the Road bikes. Not to mention the 700cm wheels in the gearing equation. Down hill I'm spunout at 32mph it was 27 before I worked on My cadence. Down hills you may see 10mph difference. With that being said I'm gonna get a dedicated road bike. Not so much for speed but overall efficancy. Besides I'm not sure those roadbike clubs will let you ride with them on a MTN Bike. Overall the biggest factor in speed is your body and lungs thus is why I'm ridding My Mountain Bike on the road building up My weekly Milage little by little. Don't matter what kinda bike ya got ya still gots to peddle it.