>I'm afraid I'm not familiar with what "class 600" motors are. How much
>current are you expecting them to draw? What is the stall current?

Graupner (www.graupner.com) rates its motors this way.

A standard R/C car motor is a 540.

A lengthened 540 (about 1cm longer) is a 550.

Then comes the 600.

The 700 motors are about 50mm dia (I forget exact dimensions and I'm
working from memory).

I use a stock 700 in my models on 12 cells for sport use.  See
http://www.rc-hydros.com for how they are used.

Andy

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