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Unread 21-08-2014, 18:41
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Re: Ideas for Ball Shifter?

Quote:
Originally Posted by magnets View Post
I'm not sure that's really ideal. With an 11:76 in low gear and a 14:74 reduction in high gear, (same C-C distance with vex pinions), you get a 1.31 spread. On a 4 inch wheel (the gears have an OD of 3.9", so that's the smallest wheel you can get), you'll see free speeds of 13.4 and 17.5 fps, both of which will have you tripping breakers with 2 or 3 CIMs per gearbox.

You'd also need to find 76 and 74 tooth gears, and put in the hole for the bushing and the circular grooves for the ball shifter components.
Whoops, I forgot about C-C distance.
Actually, you can put one shaft at an offset to the side for the low gear and put the high gear on the main shaft. You still shift between the two gears on the main shaft, but when you shift into low gear it could go through an extra reduction.
I will need to make a picture. Bascially, you have two pinions on the CIM shaft, but the 11t (low gear) pinion is mated with a gear on the side. That gear is on a shaft which connects to a small gear on the 2x1 side of the gearbox, which is mated with the main shaft. That makes a 2-stage reduction for the low gear, and a 1-stage reduction for the high gear.

Last edited by asid61 : 21-08-2014 at 18:43.