The Gray Gearless has a flexible shaft drive. They advertized it as "the strongest part of the motor", and went on to explain to prospective buyers how tough it was.
They touted the fact there was "no wasted power" from the need for bevel gears, plus Grays didn't have the weight due to "cumbersome speed retarding containing hubs". The gearless drive is "made of Chrome Vanadium, heat treated; maximum strength 250,000 pounds per square inch" and all the power from the motor is delivered smoothly to the propeller "with no chance to wear" because "the vanadium universal drive carries in a spring tube engine grease".
The downside, as mentioned in the owner's guide (not the ads) is that once a month you have to disconnect the shaft and pour heated grease into it!!
That being said, the Gray Gearless is undeniably a wonderfully fascinating motor! 
The top video to the right is a good introduction to
them by the Upper Canada Chapter of AOMCI.
"1914 Blakely rowboat motor RBM running on a 1972 Giesler Powassan 16 cedar strip boat. Blakely sold to Gray Motor company in 1914.
Subsequent motors would be badged as Gray Gearless. Both the Blakely and Gray Gearless motors are uncommon with the Blakely being exceptionally so." (See Blakely)
Posted on the Blakely page is a very thorough history of the Blakely and Gray Gearless motors.
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Gray Gearless #GG311
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Gray Gearless #GG411
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What's inside
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Instruction Manual for Attaching, Starting and
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Gray Gearless # GG1020 coming soon! |
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