If you're looking for skinnier 650b knobblies then Conti have the MudKing in 1.8 or you have the Specialized Crossroads in 1.9.
Thanks I'll take a look
Look at the Schwalbe G-One, they come in 650b as well in a 1.5 sizes, not massive but allow you ample clearance at 40c.
@Hulsroy started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
If you're looking for skinnier 650b knobblies then Conti have the MudKing in 1.8 or you have the Specialized Crossroads in 1.9.