All Bolex cameras have an 8:1 drive shaft. That means that one turn of the shaft exposes 8 frames of film. The later ones have a 1:1 shaft in addition to the 8:1 shaft.
On earlier Bolexes (for example, Rex1 as well as early non-reflex models), the center pin on the 8:1 drive shaft is 3mm in diameter. Later Bolexes have a larger 4mm center pin.
You will be asked the center pin size of your camera when you order the motor.
A 3mm coupler will not fit on a Bolex with a 4mm drive shaft. A 4mm coupler will fit on the smaller 3mm drive shaft, but it will wiggle and bind and not work properly.
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Bolex Rex 1, with 3mm drive shaft.
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Later Bolex, with 4mm drive shaft. This happens to be a Bolex M.
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Latest Bolex. Has 8:1 drive shaft and 1:1 drive shaft (the 8:1 shaft is 4mm). The later Reflex cameras are like this, as well as the Bolex S.
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Bolex EBM - They have 4mm shaft. Yes it will work on the EBM.
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Antique Bolex. No frame counter. The Revolution motor cannot drive this. |