I love Rivendell Jack Brown tires. They are a great combo of cush on a 700c wheel and low rolling resistance.
I have had Jack Brown’s on my A. Homer Hilsen for a few years, with a brief fling using the also sublime Gran Bois Cypres tires. For the past 6 months, I’ve been regularly riding a Hunqapillar with heavier Schwalbe Duremes on my work commute of 10-20 miles, and I have been gradually come to a conclusion. Heavy tires with tough sidewalls are great for avoiding flats, but I don’t like riding on them. They feel really sluggish – like I’m constantly pushing and fighting to keep the bike moving. Not fun to me. Biking should be fun.
With that in mind, I swapped out the Duremes for my extra set of Jack Browns and rode in the other day with this configuration. Yes – it made a difference. I also noticed the difference in feel of the bike frame going from the more flexy AHH to the stiffer Hunqapillar. My normal cruising speed on the flats is 15-20 mph depending on the inclines/wind/legs on the AHH. With the heavy Schwalbe Duremes (50mm) on the Hunqa, I was typically struggling to keep it at 13 mph.
Now, I’m not trying to set speed records, but I’ve found that the beauty of “road” bikes is that they typically feel more effortless on the pavement. In my many years commuting with a mountain bike with roadish tires, I know that a lot of it has to do with geometry as well, but tires DO make a big difference. That said, it’s not the diameter, it’s the weight, and the sidewall. Big cushy tires can be AWESOME if they are light and have a supple sidewall.
Yes, you will get more flats. Only you will be able to decide if the rest of the time riding is worth the few flats. I’m not in goathead country, so the biggest problem is road trash (glass, radial wires, nails). This will result in a flat every few months. I can live with this. To avoid it as much as possible, I use the Jack Brown Blue (kevlar belt) as my rear tire, and the lighter, suppler Green on the front. This keeps me pretty flat proof, as everyone knows that you always get flats on the tire that is hardest and messiest to change (rear).
Now I just need to move those fenders in a bit…