- 650B x 38c
- Black tread or Terracotta tread with skinwall
- Has a standard nylon casing and offers a true 38mm width
- Raised Pasela tread
- Made in Japan
Tested by Carytown Bicycle Co.
... The B-line tires are 650bx38 and give a ton more volume so I knew the pressure could be even lower. What I did not know is how low I could go. After a week of riding to and from work and slowly bleeding off pressure I found that 50psi was perfect. A this low an air pressure my bike now floats over the pavement making even some of the rougher sections of my ride feel like they had just been repaved. What really impressed me is that even though my pressure was this low the bike did not have any trouble going fast. I did not feel like this set up had lost even a bit of efficiency compared to the setup I just replaced. Win-win.
At some point I’ll have to try those fancy tires from Gran Bois but for the time being I’m 100% satisfied with the Soma B-line and would definitely suggest these to anyone thinking about going to 650b for this same type of use.
Gravelbike.com's 1st Impressions on the B-Line
Mounting the B-Lines on Velocity Synergy rims was a breeze. My past experience with similar tires (700x32C Paselas) had me concerned about possible hops or wobbles, but the B-Lines mounted true with only minimal adjustment of the beads. Inflating the tires to 55-60psi resulted in the familiar “pop” of the beads seating into place. Within a few days, the tires measured 37mm when pumped up to the maximum 75psi. The first ride on the B-Lines revealed a plush, “magic carpet” ride. Rough, or broken pavement went essentially unnoticed. The ride was comfortable, but still felt very lively. Cornering was predictable, and the SOMAs made the tell-tale “hum” that I’d come to expect from a high-quality tire (especially when descending). After some experimentation, I found the sweet spot to be 40-45psi up front, and 47-52psi in back (for paved riding). While certainly not a dedicated off-road tire, the B-Line is quite capable on gravel and dirt roads. Dropping the pressure 10-15% made a dramatic difference in traction and comfort (I’ve run them as low as 33psi, and I weigh 200 pounds). http://www.gravelbike.com/?p=1052