I’ve written often about the differences between road an mountain bikes – and even a “how to” on making a mountain bike fast on a budget. But what’s the raw data on the difference? I use Endomondo as a sports tracker so I actually have hard historical data on the two. Now, it must be stated prior to the examination of the data that there is a large quality gap between my mountain bike and my road bike. My mountain bike, a 2008 Trek 3700, is high end entry level while my road bike, a ’99 Trek 5200, is a legitimate high end race bike (even if it is older).
That said, here’s the data:
- One hour 20.42 mi
- 10 miles 26m:13s
- 20 km 33m:49s
- 50 km 1h:35m:59s
- One hour 16.44 mi
- 10 miles 33m:41s
- 20 km 44m:32s
- 50 km 1h:55m:08s
All of the personal bests above are from solo rides, though some of the mountain biking miles occurred on hard packed dirt roads while the road bike miles obviously occurred only on paved roads. Seven minutes over ten miles is a big deal – so is four miles in one hour. If you’re wondering why the larger minute difference between the one hour and 10 miles/20 km times, I can sprint for ten or twelve miles before I need to slow it down for a rest.
There are some obvious changes that can be made to a mountain bike to make it faster as I detailed in the previously linked post, chief among them switching out the knobby tires for slicks, a cost of $40-$50 but in my personal experience, this only allows for a 1-1.5 mph increase. In fact, I ended up “gearing out” with the slick tires (and aero bars) while riding downhill. In 21st gear (my highest on the mtb) I couldn’t pedal fast enough to make the bike go any faster – I ended up having to coast. I obviously don’t have that problem with my road bike – at least not on the hills in southeastern Michigan.
The big advantage with a mountain bike, in terms of fitness, on the other hand is that you’re working harder to push the fat tires – you literally burn more calories to go slower – a 30-60% increase in calories burned as a matter of fact, depending on the terrain.
UPDATE: I have a second, companion post, to this one in which I explored the difference between typical mountain bike tires and slicks here.