The LB1 is, arguably, the flagship model in the Mamod mobile range (excluding special editions, of course). It is certainly the biggest and heaviest. This is, I think, an early version with a red boiler shroud and brown wheels.
Like many of the other mobile models, the LB1 was based on the SA1 Roadster chassis, with double decker bus bodywork. The boiler (approx 1.75" diam x 3.25" long), cylinder (5/16" bore x 3/4" stroke) and two stage transmission are all identical to the SA1. The wheels are the same as on the SW1. Interestingly the steering linkage is the same as on the SA1 except that the wheel fixing has been modified to correct the error in geometry found on the SA1. Unfortunately, the added part of the mounting has been spot welded in place, which is a weak point. On this example, it has broken away, probably in transit.
Generally in good condition except for the broken wheel fixing, which I have repaired using solder reinforced with a nut and bolt. As acquired, it would not run reliably on steam or air. However, after lapping the port face and adjusting the reversing lever (so that it doesn't catch on the seat), it now runs ok. Perversely, it runs better in reverse than forwards!