In my last post I mentioned how I've gotten back into cycling to improve my fitness. I noticed improved stamina after only one week. It's continued to get better as time goes on.
One improvement I made to my 1999 Trek 820 mountain bike yesterday was to replace the old, knobby off road tires with a set of Bontrager H2 semi-slicks, which are better suited to the kind of riding that I'm doing now. I.e., pavement and packed gravel.
Bicycle tires with an aggressive tread pattern are better for off road use on dirt, grass, loose gravel, or similar surfaces. In contrast, smooth tires offer better traction with less rolling resistance on pavement or hard packed gravel, even when it's wet.
This morning I took the bike for a short ride with the new tires. I did 6.13 miles* along Forbidden Drive in the Valley Green section of Philadelphia's Fairmount Park. These have noticeably less rolling resistance than the knobbies, so much so that I found myself riding one or two gears higher and improved my average speed by a couple MPH, compared with previous rides on the same trail. The improved rolling speed in my case is due not only to the smooth tread but also that these are 1.5" wide, vs. the 1.95" width of my old tires.
I'm also able to run these at higher pressure, between 60 to 90 PSI, vs. 65 PSI max for the old rubber. Since a lot of my riding is on gravel I have them inflated at about 65 to 70 PSI, to provide a little cushioning. Were I to take a long ride on pavement I'd pump them up to 90 PSI.
If you have an old mountain bike laying around or pick one up cheap from a yard sale or Craigslist, you can greatly improve its rideability on hard surfaces merely by swapping out the old tubes and tires for something like the Bontragers. If you envision mixed use, there are a variety of hybrid tires available with a smooth center flanked by more aggressive knobbies that will bite when you take it off road. If you're setting up a bike as a bugout vehicle, then such hybrid tires make a lot of sense.
Another option (and one I'm still considering) is getting a second set of wheels. Most mountain bikes from good manufacturers made in the past 25 years have quick-detach wheels. So, you could have a bike setup for dirt use, and another setup for road and packed gravel riding.
* I wanted to do at least 8 miles today but it was humid and hot as balls. That just sucks the energy right out of you.