Road speed on mountain bike trails

Cycling Phun posted today about how riding on a road bike and mountain bike in the same day can lead to some interesting observations about balance, speed, and rolling resistance. I’ve certainly noticed some of the same things, so allow me to weigh in on some of the main points: 1. Balance is tougher on …

Cycling Phun posted today about how riding on a road bike and mountain bike in the same day can lead to some interesting observations about balance, speed, and rolling resistance. I’ve certainly noticed some of the same things, so allow me to weigh in on some of the main points:

1. Balance is tougher on a road bike than a mountain bike. Yes, road bikes have skinnier tires but you’re riding on a paved road vs. rocky, rooty, off camber trails so you’d think it might be a wash between the two – it’s not. I can ride my mountain bike with no hands for miles and miles on road but as soon as I take one hand off the bars on my road bike to grab a drink I can feel my life flash before my eyes. I’ll take a rocky technical trail on the MTB over a narrow highway shoulder any day.

Riding indoors (yeah that’s right) is another story though. For some reason I’m much more comfortable riding my road bike inside the house than my mountain bike. I think it has something to do with the fact that the road bike is closer to the ground but I’m not sure. In our last house I was able to ride a complete indoor circuit on the road bike – from the living room, through the dining room, out the office, and back again without putting a foot down. On the mountain bike it didn’t work so well (plus mudhunny wasn’t excited about having dirty MTB tires on her floor).

2. Road speed and trail speed are totally different. Cycling Phun touched on this but it’s foolish to think you can manage anything close to the same average speed on the trail as you can on the road. I can generally push around 17-18mph on my road bike but on the MTB in dirt a 10mph average is a fast ride. Sure you’ll get up to 25mph every now and then on a fast downhill trail but climbs, turns, roots, rocks, etc. all serve to slow you down big time on the trail. The only thing on the road that slows me down is stop lights.

Interestingly, the sensation of speed seems to be about the same on road and trail. Roads are wide and obstacles are non-existant so when I’m on a tight trail clocking 12mph it feels as fast as 30mph on the road. Kinda like when you go night riding and a 8mph ride feels like you’re racing an Indy car with one eye closed 😉

3. Rolling resistance isn’t something most mountain bike riders typically think about since on the trail gripping power is king. While it’s true that you need some good grippage on your rear wheel, I’m not afraid to rock a semi-slick tire on my front MTB wheel most days. If you’ve never seen a semi-slick tire, the side knobs are still in tact for gripping in turns while the middle knobs are flattened to give you more speed on the straights. Running a semi-slick on your front tire isn’t for everyone, especially for those who ride in sandy conditions but at least it gives me a bit of a mental speed boost on the trail.

With 29er MTB wheels now an option we’re seeing even more crossover as road designs honed for speed are adapted for the trail. Next thing you know kids will start putting drop bars on their mountain bikes to cut down on wind resistance 😉