Retro Twin

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The Retro twin was made in small numbers by André Demesse, a French expatriot living in Luxemburg. A perpteual problem with two-stroke twins is maintaining balanced induction delivery to both cylinders from a single inlet. Most in-line twins are designed to be alternate firing so that the inlet charge can alternate between cylinders. In comparison to a simultaneous firing twin, this induces a "rocking couple" about the center of mass, but is considered the lesser of two evils. The Demesse Retro Twin is almost certainly alternate firing as the long inlet path to the front cylinder would cause extreme starving in a simultaneous firing engine. even so, inertia in the inlet would likely result in the front pot running leaner than the rear unless the timings were latered to compensate.

 

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